MAX98088 - Maxim Integrated
19-5335; Rev 1; 6/11
EVALUATION KIT AVAILABLE
MAX98088
Stereo Audio Codec
with FlexSound Technology
General Description
Features
The MAX98088 is a full-featured audio codec whose high
performance and low power consumption make it ideal
for portable applications.
S 5.6mW Power Comsumption (DAC to HP at 97dB DR)
S 101dB DR Stereo DAC (8kHz < fS < 96kHz)
S 93dB DR Stereo ADC (8kHz < fS < 96kHz)
S Stereo Low EMI Class D Amplifiers
950mW/Channel (8I, VSPKVDD_ = 4.2V)
S Efficient Class H Headphone Amplifier
S Differential Receiver Amplifier/Stereo Line Outputs
S 2 Stereo Single-Ended/Mono Differential Line
Inputs
S 3 Differential Microphone Inputs
S FlexSound Technology
5-Band Parametric EQ
Automatic Level Control (ALC)
Excursion Limiter
Speaker Power Limiter
Speaker Distortion Limiter
Microphone Automatic Gain Control
and Noise Gate
S Dual I2S/PCM/TDM Digital Audio Interfaces
S Asynchronous Digital Mixing
S Supports Master Clock Frequencies from 10MHz
to 60MHz
S RF Immune Analog Inputs and Outputs
S Extensive Click-and-Pop Reduction Circuitry
S Available in 63-Bump WLP Package (3.80mm x
3.30mm, 0.4mm Pitch)
Class D speaker amplifiers provide efficient amplification
for two speakers. Low radiated emissions enable completely filterless operation. Integrated bypass switches
optionally connect an external amplifier to the transducer
when the Class D amplifiers are disabled.
The IC features a stereo Class H headphone amplifier
that utilizes a dual-mode charge pump to maximize efficiency while outputting a ground referenced signal that
does not require output coupling capacitors.
The IC also features a mono differential amplifier that can
also be configured as a stereo line output.
Two differential analog microphone inputs are available as
well as support for two PDM digital microphones. Integrated
switches allow for an additional microphone input as well
as microphone signals to be routed out to external devices.
Two flexible single-ended or differential line inputs may be
connected to an FM radio or other sources.
Integrated FlexSoundK technology improves loudspeaker performance by optimizing the signal level and frequency response while limiting the maximum distortion
and power at the output to prevent speaker damage.
Automatic gain control (AGC) and a noise gate optimize
the signal level of microphone input signals to make best
use of the ADC dynamic range.
Ordering Information appears at end of data sheet.
The device is fully specified over the -40NC to +85NC
extended temperature range.
For related parts and recommended products to use with this part,
refer to www.maxim-ic.com/MAX98088.related.
FlexSound is a trademark of Maxim Integrated Products, Inc.
Simplified Block Diagram
I2C
I2S/PCM
I2S/PCM
RECEIVER/LINEOUT AMPS
DIGITAL
AUDIO
INTERFACE
CONTROL
DIGITAL MICROPHONE
INPUT
FlexSound TECHNOLOGY
ADC
MIX
LINEIN A1
ADC
LINEIN A2
+
• 5-BAND PARAMETRIC EQ
• AUTOMATIC LEVEL CONTROL
• LOUDSPEAKER PROCESSING
• EXCURSION LIMITER
• THD LIMITER
• POWER LIMITER
• MICROPHONE PROCESSING
• AUTOMATIC GAIN CONTROL
• NOISE GATE
• ASYNCHRONOUS DIGITAL MIXING
SPEAKER AMP
DAC
SPEAKER AMP
MIX
DAC
HEADPHONE AMP
MAX98088
LINEIN B1
LINEIN B2
DIGITAL
AUDIO
INTERFACE
+
HEADPHONE AMP
����������������������������������������������������������������� Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX98088
Stereo Audio Codec
with FlexSound Technology
TABLE OF CONTENTS
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Simplified Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Functional Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Digital Input/Output Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Input Clock Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Audio Interface Timing Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Digital Microphone Timing Characterstics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
I2C Timing Characterstics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Power Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Typical Operating Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Microphone to ADC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Line to ADC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Line-In Pin Direct to ADC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Digital Loopback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Analog Loopback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
DAC to Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Line to Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
DAC to Line Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Line to Line Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
DAC to Speaker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Line to Speaker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
DAC to Headphone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Line to Headphone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Speaker Bypass Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Detailed Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
I2C Slave Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Microphone Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Line Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
ADC Input Mixers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
����������������������������������������������������������������� Maxim Integrated Products 2
MAX98088
Stereo Audio Codec
with FlexSound Technology
TABLE OF CONTENTS (continued)
Record Path Signal Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Microphone AGC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Noise Gate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
ADC Record Level Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Sidetone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Digital Audio Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Clock Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Sample Rate Converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Passband Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Playback Path Signal Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Automatic Level Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Parametric Equalizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Playback Level Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
DAC Input Mixers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Receiver Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Receiver Output Mixer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Receiver Output Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Speaker Amplifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Speaker Output Mixers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Speaker Amplifier Signal Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Excursion Limiter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Speaker Output Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Power Limiter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Distortion Limiter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Headphone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
DirectDrive Headphone Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Charge Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Class H Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Headphone Output Mixers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
Headphone Output Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Output Bypass Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Click-and-Pop Reduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Jack Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Jack Detection and Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Battery Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Device Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
����������������������������������������������������������������� Maxim Integrated Products 3
MAX98088
Stereo Audio Codec
with FlexSound Technology
TABLE OF CONTENTS (CONTINUED)
I2C Serial Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Bit Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
START and STOP Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Early STOP Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Device Revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Slave Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Write Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Read Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Applications Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Typical Operating Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Filterless Class D Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
RF Susceptibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Startup/Shutdown Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Component Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Optional Ferrite Bead Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Input Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Charge-Pump Capacitor Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Charge-Pump Flying Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Charge-Pump Holding Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Unused Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Recommended PCB Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Supply Bypassing, Layout, and Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
WLP Applications Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
����������������������������������������������������������������� Maxim Integrated Products 4
D8 INB2
E7 INB1
E9 INA2/EXTMICN
F9 INA1/EXTMICP
G8 MIC2N
G9 MIC2P
MIC2BYP
MIC1N/
F8 DIGMICCLK
MIC1P/
E8 DIGMICDATA
F7 MICBIAS
E6 JACKSNS
INABYP
MBEN
JDETEN
JACK
DETECTION
I2C
REG
+
+
EXTMIC
EXTMIC
PGAINB:
+20dB TO -6dB
INBDIFF
PGAINB:
+20dB TO -6dB
PGAINA:
+20dB TO -6dB
INADIFF
PGAINA:
+20dB TO -6dB
PA2EN:
0/20/30dB
PGAM2:
+20dB TO 0dB
PA1EN:
0/20/30dB
PGAM1:
+20dB TO 0dB
CLOCK
CONTROL
E2
MCLK
MIXADR
MIX
MIXADL
MIX
D1
MAS1
DAI1
SEL1
ADREN
ADCR
ADCL
ADLEN
BCLKS1
D4
LRCLKS1
D2
LBEN2
MODE1
AVFLT
MIX
MUX
DATA
OUTPUT
+
G7
PORT S2
EQ2EN
DV1:
0dB TO -15dB
HIZOFF2
MODE1
DVFLT
AUDIO/
VOICE
FILTERS
DCB2
MIXDAR
MIX
MIXDAL
MIX
DAREN
DACR
DALEN
DACL
C6, C7, D5, D6, D7, E3
N.C.
DATA
INPUT
SDIEN2
G4
DVDD
G2
DVDDS2
FlexSoundTM
TECHNOLOGY
AUDIO
FILTERS
DVEQ2:
0dB TO -15dB
G3
SDINS2
DATA
OUTPUT
MAS2
LBEN1
DV2:
0dB TO -15dB
EXCURSION LIMITER
EQ1EN
G1
SDOUTS2
FRAME
CLOCK
LRCLK2
5-BAND
PARAMETRIC
EQ
DVEQ1:
0dB TO -15dB
MULTI BAND ALC
F1
AVRG: 0/6/
12/18dB
AVR:0dB
TO -15dB
F3
LRCLKS2
BIT
CLOCK
BCLK2
DV1G:
0/6/12/18dB
5-BAND
PARAMETRIC
EQ
LTEN1
+
MAS2
AGND
SAMPLE RATE
CONVERTER
AUDIO/
VOICE
FILTERS
DATA
INPUT
SDIEN1
DVST:
0dB TO -60dB
HIZOFF1
DAI2
SEL2
F2
BCLKS2
E1
DVDDS1
DGND
SRMIX_
MODE
E4
SDINS1
NOISE GATE
DSTS
SIDETONE
SDOUT1
MAS1
PORT S1
SDOUTS1
FRAME
CLOCK
LRCLK1
AVLG: 0/6/
12/18dB
AVL:0dB
TO -15dB
AUTOMATIC
GAIN
CONTROL
BIT
CLOCK
BCLK1
E5
SDIN1
F5
SDOUT2
F4
SDIN2
SDA SCL IRQ
G5
AVDD
MIXHPR
MIX
MIXHPL
MIX
MIXSPR
MIX
MIXSPL
MIX
MIXRECR
MIX
MIXRECL
MIX
MIXHPR_
PATH SEL
MIXHPL_
PATH SEL
CHARGE
PUMP
HPREN
HPVOR:
+3dB TO -67dB
HPLEN
B9
A8
SPKBYP
POWER/
DISTORTION LIMITER
RECREN
0dB
RECBYP
RECLEN
0dB
HPVOLL:
+3dB TO -67dB
SPREN
+6dB
SPLEN
+6dB
RECVOLR:
+8dB TO -62dB
RECVOLL:
+8dB TO -62dB
B8
B7
HPVDD HPVSS C1N C1P
SPVOLR:
+8dB TO -62dB
SPVOLL:
+8dB TO -62dB
LINEMODE
MAX98088
BIAS
REF
A7
A9
PVDD
D9
C8
C9
A2, B2
A1, B1
C1, C2
C3, D3
C4, C5
A5, B5
A4, B4
A3, B3
B6
A6
F6
G6
HPGND
HPR
HPSNS
HPL
SPKRGND
SPKRN
SPKRP
SPKRVDD
SPKLGND
SPKLN
SPKLP
SPKLVDD
RECN/
LOUTR/
RXINN
RECP/
LOUTL/
RXINP
REG
MAX98088
Stereo Audio Codec
with FlexSound Technology
Functional Diagram
����������������������������������������������������������������� Maxim Integrated Products 5
MAX98088
Stereo Audio Codec
with FlexSound Technology
ABSOLUTE MAXIMUM RATINGS
(Voltages with respect to AGND.)
DVDD, AVDD, PVDD, HPVDD...............................-0.3V to +2.2V
SPKLVDD, SPKRVDD, DVDDS1, DVDDS2...........-0.3V to +6.0V
DGND, HPGND, SPKLGND, SPKRGND...............-0.1V to +0.1V
HPVSS................................ (HPGND - 2.2V) to (HPGND + 0.3V)
C1N..................................... (HPVSS - 0.3V) to (HPGND + 0.3V)
C1P......................................(HPGND - 0.3V) to (HPVDD + 0.3V)
REF, MICBIAS.................................. -0.3V to (SPKLVDD + 0.3V)
MCLK, SDINS1, SDINS2, JACKSNS,
SDA, SCL, IRQ..................................................-0.3V to +6.0V
LRCLKS1, BCLKS1, SDOUTS1.......... -0.3V to (DVDDS1 + 0.3V)
LRCLKS2, BCLKS2, SDOUTS2.......... -0.3V to (DVDDS2 + 0.3V)
REG, INA1/EXTMICP, INA2/EXTMICN, INB1,
INB2, MIC1P/DIGMICDATA, MIC1N/DIGMICCLK,
MIC2P, MIC2N...................................................-0.3V to +2.2V
HPSNS................................ (HPGND - 0.3V) to (HPGND + 0.3V)
HPL, HPR............................. (HPVSS - 0.3V) to (HPVDD + 0.3V)
RECP/LOUTL/RXINP, RECN/LOUTR/
RXINN......................(SPKLGND - 0.3V) to (SPKLVDD + 0.3V)
SPKLP, SPKLN............(SPKLGND - 0.3V) to (SPKLVDD + 0.3V)
SPKRP, SPKRN..........(SPKRGND - 0.3V) to (SPKRVDD + 0.3V)
Continuous Power Dissipation (TA = +70NC)
63-Bump WLP (derate 25.6mW/NC above +70NC).........2.05W
Operating Temperature Range........................... -40NC to +85NC
Storage Temperature Range............................. -65NC to +150NC
Soldering Temperature (reflow).......................................+260NC
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
POWER SUPPLY
Supply Voltage Range
Guaranteed by PSRR
VSPKLVDD, VSPKRVDD
2.8
VDVDD, VAVDD, VPVDD
1.65
VDVDDS1, VDVDDS2
1.65
Analog
Full-duplex 8kHz mono,
Speaker
receiver output, MAS = 1
Digital
Total Supply Current
(Notes 2 and 3)
Shutdown Supply Current
(Note 2)
IVDD
5.5
1.8
2
4.5
8
1.6
2.3
1.3
2
DAC playback 48kHz
stereo, headphone
outputs, MAS = 1
Analog
1.9
3
Speaker
0.001
0.0058
Digital
2.47
3.5
DAC playback 48kHz
stereo, speaker outputs,
MAS = 1
Analog
3.6
6.5
Speaker
6.41
8.5
Digital
2.49
3.5
Analog
0.2
2
Speaker
0.01
1
1
5
TA = +25NC
Digital
V
3.6
mA
FA
REF Voltage
2.5
V
REG Voltage
0.79
V
Shutdown to Full Operation
VSEN = 0
30
VSEN = 1
17
ms
����������������������������������������������������������������� Maxim Integrated Products 6
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
DR
fS = 8kHz, MODE = 0 (IIR voice), AVMICPRE_ = 0dB
(Note 4)
88
VIN = 0.1VP-P, fS = 8kHz, f = 1kHz
-78
AVMICPRE_ = 0dB, VIN = 1VP-P, f = 1kHz
AVMICPRE_ = +30dB, VIN = 32mVP-P, f = 1kHz
-85
VIN = 100mVP-P, f = 217Hz
74
MAX
UNITS
MICROPHONE TO ADC PATH
Dynamic Range
Total Harmonic Distortion +
Noise
THD+N
Common-Mode Rejection
Ratio
CMRR
VAVDD = 1.65V to 1.95V, input referred,
MIC inputs floating
Power-Supply Rejection Ratio
PSRR
Path Phase Delay
dB
-71
50
dB
62
f = 217Hz, VRIPPLE = 200mVP-P, input referred
62
f = 1kHz, VRIPPLE = 200mVP-P, input referred
62
f = 10kHz, VRIPPLE = 200mVP-P, input referred
53
1kHz, 0dB input,
highpass filter disabled
measured from analog
input to digital output
dB
MODE = 0 (IIR voice)
8kHz
2.2
MODE = 0 (IIR voice)
16kHz
1.1
MODE = 1 (FIR audio)
8kHz
4.5
MODE = 1 (FIR audio)
48kHz
0.76
dB
ms
MICROPHONE PREAMP
Full-Scale Input
AVMICPRE_ = 0dB
1.05
PA1EN/PA2EN = 01
Preamplifier Gain
AVMICPRE_ (Note 5)
PGA Gain
AVMICPGA_ (Note 5)
MIC Input Resistance
RIN_MIC
VP-P
0
PA1EN/PA2EN = 10
19.5
20
20.5
PA1EN/PA2EN = 11
29.5
30
30.5
19
20
21
PGAM1/PGAM2 = 0x00
PGAM1/PGAM2 = 0x14
All gain settings, measured at MIC1P/
MIC1N/MIC2P/MIC2N
0
50
dB
dB
kI
����������������������������������������������������������������� Maxim Integrated Products 7
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
2.15
UNITS
MICROPHONE BIAS
MICBIAS Output Voltage
2.2
2.25
V
Load Regulation
VMICBIAS
ILOAD = 1mA to 2mA
0.5
4.5
mV
Line Regulation
VSPKLVDD = 2.8V to 5.5V
110
f = 217Hz, VRIPPLE (SPKLVDD) = 100mVP-P
92
f = 10kHz, VRIPPLE (SPKLVDD) = 100mVP-P
83
A-weighted, f = 20Hz to 20kHz
3.9
P-weighted, f = 20Hz to 4kHz
2.1
f = 1kHz
50
IMIC1_ = 100mA, INABYP = MIC2BYP = 1,
VMIC2_ = VINA_ = 0V, AVDD, TA = +25NC
5
Ripple Rejection
Noise Voltage
ILOAD = 1mA
FV
dB
FVRMS
nV/√Hz
MICROPHONE BYPASS SWITCH
On-Resistance
RON
Total Harmonic Distortion +
Noise
30
I
VIN = 2VP-P, VCM = 0.9V, RL = 10kI,
f = 1kHz, INABYP = MIC2BYP = 1
-80
dB
Off-Isolation
VIN = 2VP-P, VCM = 0.9V, RL = 10kI, f = 1kHz
60
dB
Off-Leakage Current
VMIC1_ = [0V, AVDD], VMIC2_/VINA_ =
[AVDD, 0V]
THD+N
-1
+1
FA
LINE INPUT TO ADC PATH
Dynamic Range (Note 4)
Total Harmonic Distortion +
Noise
DR
THD+N
Gain Error
INA pin direct, fS = 48kHz, MODE = 1
(FIR audio)
93
VIN = 1VP-P, f = 1kHz
-82
DC accuracy VAVDD = 1.65V to 1.95V, input referred,
line inputs floating, TA = +25NC
Power-Supply Rejection Ratio
PSRR
1
57
dB
-74
dB
%
68
f = 217Hz, VRIPPLE = 200mVP-P,
AVADC = 0dB, input referred
63
f = 1kHz, VRIPPLE = 200mVP-P,
AVADC = 0dB, input referred
63
f = 10kHz, VRIPPLE = 200mVP-P,
AVADC = 0dB, input referred
57
dB
����������������������������������������������������������������� Maxim Integrated Products 8
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
LINE INPUT PREAMP
Full-Scale Input
VIN
AVPGAIN_ = 0dB
1
AVPGAIN_ = -6dB
1.4
TA = +25NC
AVPGAIN_
(Note 5)
Level Adjust Gain
PGAINA/PGAINB = 0x0
19
20
21
PGAINA/PGAINB = 0x1
13
14
15
PGAINA/PGAINB = 0x2
2
3
4
PGAINA/PGAINB = 0x4
-4
-3
-2
PGAINA/PGAINB = 0x5,
0x6, 0x7
-7
-6
-5
14.5
21
28
PGAINA/PGAINB = 0x3
AVPGAIN_ = +20dB
0
AVPGAIN_ = +14dB
Input Resistance
RIN
AVPGAIN_ = +3dB
20
AVPGAIN_ = 0dB
7.5
INAEXT/INBEXT = 1
10
14
kI
20
AVPGAIN_ = -6dB
RIN_FB
dB
20
AVPGAIN_ = -3dB
Feedback Resistance
VP-P
20
TA = +25NC
18
TA = TMIN to TMAX
16
20
22
24
kI
ADC LEVEL CONTROL
ADC Level Adjust Range
AVADCLVL AVL/AVR = 0xF to 0x0 (Note 5)
-12
ADC Level Step Size
ADC Gain Adjust Range
+3
1
AVADCGAIN AVLG/AVRG = 00 to 11 (Note 5) 0
ADC Gain Adjust Step Size
dB
dB
18
6
dB
dB
ADC DIGITAL FILTERS
VOICE MODE IIR LOWPASS FILTER (MODE1 = 0)
Passband Cutoff
fPLP
Passband Ripple
Ripple limit cutoff
0.441 x fs
-3dB cutoff
0.449 x fs
f < fPLP
Stopband Cutoff
-0.1
fSLP
Stopband Attenuation
(Note 6)
Hz
+0.1
0.47 x fS
f > fSLP
74
dB
Hz
dB
����������������������������������������������������������������� Maxim Integrated Products 9
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
VOICE MODE IIR HIGHPASS FILTER (MODE1 = 0)
Passband Cutoff
(-3dB from Peak)
fAHPPB
Stopband Cutoff
(-30dB from Peak)
fAHPSB
DC Attenuation
DCATTEN
AVFLT = 0x1 (Elliptical tuned for fS = 16kHz +
217Hz notch)
0.0161
x fS
AVFLT = 0x2 (500Hz Butterworth tuned for fS =
16kHz)
0.0319
x fS
AVFLT = 0x3 (Elliptical tuned for fS = 8kHz +
217Hz notch)
0.0321
x fS
AVFLT = 0x4 (500Hz Butterworth tuned for fS =
8kHz)
0.0632
x fS
AVFLT = 0x5 (fS/240 Butterworth)
0.0043
x fS
AVFLT = 0x1 (Elliptical tuned for fS = 16kHz +
217Hz notch)
0.0139
x fS
AVFLT = 0x2 (500Hz Butterworth tuned for fS =
16kHz)
0.0156
x fS
AVFLT = 0x3 (Elliptical tuned for fS = 8kHz +
217Hz notch)
0.0279
x fS
AVFLT = 0x4 (500Hz Butterworth tuned for fS =
8kHz)
0.0312
x fS
AVFLT = 0x5 (fS/240 Butterworth)
0.0018
x fS
Hz
90
AVFLT ≠ 000
Hz
dB
STEREO AUDIO MODE FIR LOWPASS FILTER (MODE1 = 1, DHF1 = 0, LRCLK < 50kHz)
Ripple limit cutoff
Passband Cutoff
fPLP
Passband Ripple
-3dB cutoff
0.43 x fS
0.48 x fS
-6.02dB cutoff
0.5 x fS
f < fPLP
Stopband Cutoff
-0.1
fSLP
Stopband Attenuation
(Note 6)
Hz
+0.1
0.58 x fS
f < fSLP
60
dB
Hz
dB
ADC STEREO AUDIO MODE FIR LOWPASS FILTER (MODE1 = 1, DHF1 = 1, LRCLK > 50kHz)
Passband Cutoff
fPLP
Passband Ripple
Ripple limit cutoff
0.208 x fS
-3dB cutoff
0.28 x fS
-0.1
f < fPLP
Stopband Cutoff
fSLP
Stopband Attenuation
Hz
+0.1
0.417 x fS
f < fSLP
60
dB
Hz
dB
���������������������������������������������������������������� Maxim Integrated Products 10
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
ADC STEREO AUDIO MODE DC BLOCKING HIGHPASS FILTER (MODE1 = 1)
Passband Cutoff
(-3dB from Peak)
fAHPPB
AVFLT ≠ 000
DC Attenuation
DCAtten
AVFLT ≠ 000
0.000125
x fS
90
Hz
dB
MICROPHONE AUTOMATIC GAIN CONTROL
AGC Hold Duration
AGC Attack Time
AGC Release Time
AGC Threshold Level
AGCHLD = 01
50
AGCHLD = 11
400
AGCATK = 00
2
AGCATK = 11
123
AGCRLS = 000
0.078
AGCRLS = 111
10
AGCTH = 0x0 to 0xF
-3
AGC Threshold Step Size
ms
ms
s
+18
1
AGC Gain
(Note 5)
dB
dB
0
20
dB
-64
-16
dB
0
12
dB
ADC NOISE GATE
NG Threshold Level
ANTH = 0x3 to 0xF, referred to 0dBFS
NG Attenuation
(Note 5)
ADC-TO-DAC DIGITAL SIDETONE (MODE = 0)
Sidetone Gain Adjust Range
AVSTGA
DVST = 0x01
-0.5
DVST = 0x1F
-60.5
Sidetone Gain Adjust Step
Size
dB
2
1kHz, 0dB input, highpass filter
disabled
Sidetone Path Phase Delay
8kHz
2.2
16kHz
1.1
dB
ms
ADC-TO-DAC DIGITAL LOOP-THROUGH PATH Dynamic Range (Note 4)
Total Harmonic Distortion +
Noise
DR
THD+N
fS = 48kHz, MCLK = 12.288MHz, MODE = 1
(FIR audio), MIC to HP output, TA = +25NC
83
f = 1kHz, fS = 48kHz, MCLK = 12.288MHz, MODE
= 1 (FIR audio), MIC to HP output
93
dB
81
dB
DAC LEVEL CONTROL
DAC Attenuation Range
AVDACATTN DV_ = 0xF to 0x0 (Note 5)
-15
AVDACGAIN DV1G = 00 to 11 (Note 5)
0
DAC Attenuation Step Size
DAC Gain Adjust Range
DAC Gain Adjust Step Size
0
1
dB
18
6
dB
dB
dB
���������������������������������������������������������������� Maxim Integrated Products 11
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DAC DIGITAL FILTERS
VOICE MODE IIR LOWPASS FILTER (MODE1 = 0) Passband Cutoff
fPLP
Passband Ripple
Stopband Cutoff
Ripple limit cutoff
0.448 x fS
-3dB cutoff
0.451 x fS
f < fPLP
-0.1
f > fSLP
75
Hz
+0.1
fSLP
Stopband Attenuation (Note 6)
0.476 x fS
dB
Hz
dB
VOICE MODE IIR HIGHPASS FILTER (MODE1 = 0)
Passband Cutoff
(-3dB from Peak)
fDHPPB
Stopband Cutoff
(-30dB from Peak)
fDHPSB
DC Attenuation
DVFLT = 0x1 (Elliptical tuned for fS = 16kHz +
217Hz notch)
0.0161
x fS
DVFLT = 0x2 (500Hz Butterworth tuned for fS =
16kHz)
0.0312
x fS
DVFLT = 0x3 (Elliptical tuned for fS = 8kHz +
217Hz notch)
0.0321
x fS
DVFLT = 0x4 (500Hz Butterworth tuned for fS =
8kHz)
0.0625
x fS
DVFLT = 0x5 (fs/240 Butterworth)
0.0042
x fS
DVFLT = 0x1 (Elliptical tuned for fS = 16kHz +
217Hz notch)
0.0139 x fS
DVFLT = 0x2 (500Hz Butterworth tuned for fS =
16kHz)
0.0156 x fS
DVFLT = 0x3 (Elliptical tuned for fS = 8kHz +
217Hz notch)
0.0279 x fS
DVFLT = 0x4 (500Hz Butterworth tuned for fS =
8kHz)
0.0312 x fS
DVFLT = 0x5 (fS/240 Butterworth)
0.0021 x fS
DCATTEN DVFLT ≠ 000
Hz
Hz
85
dB
STEREO AUDIO MODE FIR LOWPASS FILTER (MODE1 = 1, DHF1/DHF2 = 0, LRCLK < 50kHz)
Ripple limit cutoff
Passband Cutoff
fPLP
Passband Ripple
-3dB cutoff
0.43 x fS
0.47 x fS
-6.02dB cutoff
0.5 x fS
f < fPLP
Stopband Cutoff
-0.1
fSLP
Stopband Attenuation (Note 6)
Hz
+0.1
0.58 x fS
f > fSLP
60
dB
Hz
dB
���������������������������������������������������������������� Maxim Integrated Products 12
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
STEREO AUDIO MODE FIR LOWPASS FILTER (MODE1 = 1, DHF1/DHF2 = 1 for LRCLK > 50kHz)
Passband Cutoff
fPLP
Passband Ripple
Ripple limit cutoff
0.24 x fS
-3dB cutoff
0.31 x fS
f < fPLP
Stopband Cutoff
Hz
-0.1
+0.1
fSLP
Stopband Attenuation
(Note 6)
0.477 x fS
f < fSLP
60
dB
Hz
dB
STEREO AUDIO MODE DC BLOCKING HIGHPASS FILTER
Passband Cutoff
(-3dB from Peak)
0.000104
x fS
fDHPPB
DVFLT ≠ 000 (DAI1), DCB2 = 1 (DAI2)
DCATTEN
DVFLT ≠ 000 (DAI1), DCB2 = 1 (DAI2)
90
dB
Dual Band Lowpass Corner
Frequency
ALCMB = 1
5
kHz
Dual Band Highpass Corner
Frequency
ALCMB = 1
5
kHz
DC Attenuation
Hz
AUTOMATIC LEVEL CONTROL
Gain Range
Low-Signal Threshold
ALCTH = 111 to 001
Release Time
0
12
dB
-48
-12
dBFS
ALCRLS = 101
0.25
ALCRLS = 000
8
s
PARAMETRIC EQUALIZER
Number of Bands
5
Per Band Gain Range
Preattenuator Gain Range
(Note 5)
Bands
-12
+12
dB
-15
0
dB
Preattenuator Step Size
1
dB
fS = 48kHz, f = 1kHz (Note 4)
96
dB
f = 1kHz, POUT = 15mW, RREC = 32I
-70
DAC TO RECEIVER AMPLIFIER PATH
Dynamic Range
DR
Total Harmonic Distortion +
Noise
THD+N
VSPKLVDD = 2.8V to 5.5V, TA = +25NC
Power-Supply Rejection Ratio
Click-and-Pop Level
PSRR
KCP
64
dB
75
f = 217Hz, VRIPPLE = 200mVP-P
f = 1kHz, VRIPPLE = 200mVP-P
-59
f = 10kHz, VRIPPLE = 200mVP-P
-59
Peak voltage, A-weighted, 32
samples per second, AVREC =
0dB
-63
-59
Into shutdown
-68
Out of shutdown
-72
dB
dBV
���������������������������������������������������������������� Maxim Integrated Products 13
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
LINE INPUT TO RECEIVER AMPLIFIER PATH
Dynamic Range (Note 4)
Total Harmonic Distortion +
Noise
Click-and-Pop Level
DR
Referenced to full-scale output level
THD+N
94
dB
-64
dB
KCP
Peak voltage, A-weighted, 32
samples per second, AVREC =
0dB
POUT
RREC = 32I, f = 1kHz, THD = 1%
83
mW
(Note 7)
1
VRMS
Into shutdown
-51
Out of shutdown
-49
dBV
RECEIVER AMPLIFIER
Output Power
Full-Scale Output
Volume Control (Note 5)
AVREC
Volume Control Step Size
Mute Attenuation
Capacitive Drive Capability
RECVOL = 0x00
-62
RECVOL = 0x1F
8
+8dB to +6dB
0.5
+6dB to +0dB
1
0dB to -14dB
2
-14dB to -38dB
3
-38dB to -62dB
4
f = 1kHz
88
No sustained oscillations
RREC = 32I
500
RREC = J
100
dB
dB
dB
pF
DAC TO LINE OUT AMPLIFIER PATH
Dynamic Range (Note 4)
Total Harmonic Distortion +
Noise
DR
THD+N
fS = 48kHz, f = 1kHz
f = 1kHz, RL = 1kI
83
96
-78
dB
-72
dB
LINE INPUT TO LINE OUT AMPLIFIER PATH
Dynamic Range (Note 4)
Total Harmonic Distortion +
Noise
DR
THD+N
Referenced to full-scale output level
92
dB
f = 1kHz, RL = 10kI
76
dB
VP-P
Full-Scale Output
(Note 7)
2
Mute Attenuation
f = 1kHz
85
Output Offset Voltage
Capacitive Drive Capability
VOS
AVREC_ = -62dB
Q3.0
No sustained oscillations, RL = 1kI
500
dB
Q4
mV
pF
���������������������������������������������������������������� Maxim Integrated Products 14
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DAC TO SPEAKER AMPLIFIER PATH
Total Harmonic Distortion +
Noise
THD+N
Crosstalk
f = 1kHz, POUT = 200mW, ZSPK = 8I + 68FH
-68
dB
SPKL to SPKR and SPKR to SPKL,
POUT = 640mW, f = 1kHz
-88
dB
53
FVRMS
Output Noise
Click-and-Pop Level
KCP
Peak voltage, A-weighted,
32 samples per second,
AVSPK_ = 0dB
Into shutdown
65
Out of shutdown
66
dBV
MIC INPUT TO SPEAKER AMPLIFIER PATH
Dynamic Range (Note 4)
Total Harmonic Distortion +
Noise
Click-and-Pop Level
DR
Referenced to full-scale output level, AVSPK_ = 0dB
82
dB
f = 1kHz, POUT = 200mW, RL = 8I + 68FH
71
dB
KCP
Peak voltage, A-weighted, 32
samples per second, AVSPK_
= 0dB
Into shutdown
55
Out of shutdown
52
POUT
f = 1kHz,
THD = 1%,
ZSPK = 8I +
68FH
THD+N
dBV
SPEAKER AMPLIFIER
Output Power
Full-Scale Output
VSPKLVDD = VSPKRVDD = 5.0V
1323
VSPKLVDD = VSPKRVDD = 4.2V
VSPKLVDD = VSPKRVDD = 3.7V
914
VSPKLVDD = VSPKRVDD = 3.2V
514
(Note 7)
Volume Control
AVSPK_
Volume Control Step Size
Mute Attenuation
Output Offset Voltage
VOS
(Note 5)
mW
700
2
SPVOLL/SPVOLR = 0x00
-62
SPVOLL/SPVOLR = 0x1F
+8
+8dB to +6dB
0.5
+6dB to +0dB
1
0dB to -14dB
2
-14dB to -38dB
3
-38dB to -64dB
4
f = 1kHz
86
AVSPK_ = -61dB, TA = +25NC
Q0.5
VRMS
dB
dB
dB
Q3
mV
���������������������������������������������������������������� Maxim Integrated Products 15
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
1000
Hz
EXCURSION LIMITER
Upper Corner Frequency
Range
DHPUCF = 001 to 100
Lower Corner Frequency
DHPLCF = 01 to 10
400
DHPUCF = 000 (fixed mode)
100
DHPUCF = 001
200
DHPUCF = 010
300
DHPUCF = 011
400
Biquad Minimum Corner
Frequency
400
DHPUCF = 100
ZSPK = 8I + 68FH,
VSPKLVDD = VSPKRVDD =
5.5V, AVSPK_ = 8dB
Threshold Voltage
Release Time
Hz
Hz
500
DHPTH = 000
0.34
DHPTH = 111
0.95
ALCRLS = 101
0.25
ALCRLS = 000
4
VP
s
POWER LIMITER
Attenuation
-64
ZSPK = 8I + 68FH,
VSPKLVDD = VSPKRVDD =
5.5V, AVSPK_ = 8dB
Threshold
Time Constant 1
tPWR1
Time Constant 2
tPWR2
Weighting Factor
kPWR
PWRTH = 0x1
0.08
PWRTH = 0xF
1.23
PWRT1 = 0x1
0.5
PWRT1 = 0xF
8.7
PWRT2 = 0x1 to 0xF
0.5
PWRT2 = 0xF
8.7
PWRK = 000 to 111
12.5
dB
W
s
min
100
%
DISTORTION LIMITER Distortion Limit
Release Time Constant
THDCLP = 0x1
<1
THDCLP = 0xF
24
THDT1 = 000
0.76
THDT1 = 111
6.2
%
s
���������������������������������������������������������������� Maxim Integrated Products 16
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DAC TO HEADPHONE AMPLIFIER PATH
Master or slave mode
Dynamic Range (Note 4)
Total Harmonic Distortion +
Noise
Crosstalk
DR
THD+N
fS = 48kHz
f = 1kHz, POUT = 20mW
Slave mode
97
Low power mode,
TA = +25NC
95
PSRR
97
-85
RHP = 32I
-92
HPL to HPR and HPR to HPL, POUT = 5mW,
f = 1kHz, RHP = 32I
46
72
f = 1kHz, VRIPPLE = 200mVP-P,
AVHP_ = 0dB
63
f = 10kHz, VRIPPLE = 200mVP-P,
AVHP_ = 0dB
43
MODE = 0 (voice)
8kHz
2.2
MODE = 0 (voice)
16kHz
1.1
MODE = 1 (music)
8kHz
4.5
MODE = 1 (music)
48kHz
0.76
1
1
Peak voltage, A-weighted,
32 samples per second,
AVHP_ = 0dB
dB
dB
ms
Channel Gain Mismatch
KCP
dB
54
Gain Error
Click-and-Pop Level
-64
79.5
f = 217Hz, VRIPPLE = 200mVP-P,
AVHP_ = 0dB
1kHz, 0dB input, highpass
filter disabled measured
from digital input to analog
output
DAC Path Phase Delay
dB
RHP = 16I
VAVDD = VPVDD = 1.65V to 2.0V
Power-Supply Rejection Ratio
101
Into shutdown
-62
Out of shutdown
-63
5
%
%
dBV
LINE INPUT TO HEADPHONE AMPLIFIER PATH Total Harmonic Distortion +
Noise
THD+N
VIN = 1VP-P, f =1kHz, RHP = 32I Dynamic Range (Note 4)
Click-and-Pop Level
KCP
Peak voltage, A-weighted,
32 samples per second,
AVHP_ = 0dB
81
dB
92.5
dB
Into shutdown
-62
Out of shutdown
-63
dBV
���������������������������������������������������������������� Maxim Integrated Products 17
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
HEADPHONE AMPLIFIER
Output Power
POUT
Positive Charge-Pump Output
Voltage
HPVDD
Negative Charge-Pump
Output Voltage
HPVSS
Output Voltage Threshold
(Output Voltage at which
the Charge Pump Switches
Modes; VOUT Rising;
Transition from Split to Invert
Mode)
VTH
Full-Scale Output
Volume Control
AVHP_
Volume Control Step Size
f = 1kHz, THD = 1%
RHP = 32I
30
RHP = 16I
38
VOUT ≤ VPVDD x 0.25V, RHP = J
VOUT > VPVDD x 0.25V, RHP = J
PVDD/2
VOUT ≤ VPVDD x 0.25V, RHP = J
-PVDD/2
VOUT > VPVDD x 0.25V, RHP = J
-PVDD
RL = J
QPVDD
x 0.25
V
(Note 7)
1
VRMS
(Note 5)
HPVOL_ = 0x00
-67
HPVOL_ = 0x1F
+3
+3dB to +1dB
0.5
+1dB to -5dB
1
-5dB to -19dB
2
-19dB to -43dB
3
VOS
Capacitive Drive Capability
AVHP_ = -67dB
No sustained oscillations
V
dB
dB
4
f = 1kHz
Output Offset Voltage
V
PVDD
-43dB to -67dB
Mute Attenuation
mW
100
TA = +25NC
Q0.5
TA = TMIN to TMAX
dB
Q1
Q3
RHP = 32I
500
RHP = J
100
mV
pF
SPEAKER BYPASS SWITCH
On-Resistance
RON
Total Harmonic Distortion +
Noise
THD+N
ISPKL_ = 100mA, SPKBYP = 1,
VRXIN_ = [0V, VSPKLVDD]
2.8
VIN = 2VP-P, VCM = VSPKLVDD/2, RS = 10I
ZSPK = 8I + 68FH, f = 1kHz,
RS = 0I
SPKBYP = 1
Off-Isolation
VIN = 2VP-P, VCM = VSPKLVDD/2,
ZSPK = 8I + 68FH, f = 1kHz
Off-Leakage Current
VRXIN_ = [0V, VSPKLVDD],
VSPKL_ = [VSPKLVDD, 0V]
I
60
dB
60
96
-20
dB
+20
FA
���������������������������������������������������������������� Maxim Integrated Products 18
MAX98088
Stereo Audio Codec
with FlexSound Technology
ELECTRICAL CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR
to HPGND. Line out loads (RLOAD) connected from LOUTL or LOUTR to SPKLGND. RLOAD = RHP = J, RREC = J, ZSPK = J, CREF
= 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_ = +20dB, AVMICPGA_ = 0dB, AVDACATTN
= 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ = 0dB, AVREC = 0dB, AVSPK_ = 0dB,
MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = TMIN to TMAX, unless otherwise noted. Typical values are at +25NC.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
RECEIVER BYPASS SWITCH
IRECP = 100mA, RECBYP = 1, VRECN = [0V,
VSPKLVDD]
2
I
VIN = 2VP-P, VCM = VSPKLVDD/2, ZSPK = 8I +
68FH, f = 1kHz, RECBYP = 1, RS = 0I
60
dB
Off-Isolation
VIN = 2VP-P, VCM = VSPKLVDD/2, ZSPK = 8I +
68FH, f = 1kHz
84
dB
Off-Leakage Current
VRECP = [0V, VSPKLVDD], VRECN =
[VSPKLVDD, 0V]
On-Resistance
RON
Total Harmonic Distortion +
Noise
THD+N
-15
+15
FA
JACK DETECTION
SHDN = 1, JACKSNS rising
JACKSNS Threshold
0.92 x
0.95 x
0.98 x
VMICBIAS VMICBIAS VMICBIAS
SPKLVDD - 0.7
SHDN = 0, JKSNS
JACKSNS Sense Voltage
SPKLVDD
SHDN = 0
VJACKSNS = 0V
JACKSNS Sense Current
V
4
V
10
FA
5.6
V
BATTERY ADC
Input Voltage Range
2.6
LSB Size
0.1
V
DIGITAL INPUT/OUTPUT CHARACTERISTICS
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V, TA = +25NC, unless otherwise noted.)
(Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MCLK
Input High Voltage
VIH
Input Low Voltage
VIL
Input Leakage Current
IIH, IIL
1.2
VDVDD = 2.0V, VIN = 0V, 5.5V; TA = +25°C
V
-1
Input Capacitance
0.6
V
+1
FA
10
pF
SDINS1, BCLKS1, LRCLKS1—INPUT
Input High Voltage
VIH
Input Low Voltage
VIL
0.7 x
DVDDS1
0.29 x
DVDDS1
Input Hysteresis
200
Input Leakage Current
Input Capacitance
V
IIH, IIL
VDVDDS1 = 3.6V, VIN = 0V, 3.6V; TA = +25°C
-1
mV
+1
10
V
FA
pF
���������������������������������������������������������������� Maxim Integrated Products 19
MAX98088
Stereo Audio Codec
with FlexSound Technology
DIGITAL INPUT/OUTPUT CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V, TA = +25NC, unless otherwise noted.)
(Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
0.4
V
BCLKS1, LRCLKS1, SDOUTS1—OUTPUT
Output Low Voltage
Output High Voltage
Input Leakage Current
VOL
VOH
IIH, IIL
VDVDDS1 = 1.65V, IOL = 3mA
VDVDDS1 = 1.65V, IOH = 3mA VDVDD = 2.0V, VIN = 0V, 5.5V; TA = +25°C,
high-impedance state
DVDDS1
- 0.4
V
-1
+1
FA
SDINS2, BCLKS2, LRCLKS2—INPUT
Input High Voltage
VIH
Input Low Voltage
VIL
0.7 x
DVDDS2
V
0.29 x
DVDDS2
Input Hysteresis
200
Input Leakage Current
IIH, IIL
VDVDDS2 = 3.6V, VIN = 0V, 3.6V; TA = +25°C
-1
Input Capacitance
V
mV
+1
10
FA
pF
BCLKS2, LRCLKS2, SDOUTS2—OUTPUT
Output Low Voltage
VOL
VDVDDS2 = 1.65V, IOL = 3mA
Output High Voltage
VOH
VDVDDS2 = 1.65V, IOH = 3mA
Input Leakage Current
IIH, IIL
VDVDD = 2.0V, VIN = 0V, 5.5V; TA = +25NC,
high-impedance state
0.4
DVDDS2
- 0.4
V
V
-1
+1
FA
SDA, SCL—INPUT
Input High Voltage
VIH
Input Low Voltage
VIL
0.7 x
DVDD
V
0.3 x
DVDD
Input Hysteresis
210
Input Leakage Current
IIH, IIL
VDVDD = 2.0V, VIN = 0V, 5.5V; TA = +25NC
-1
Input Capacitance
mV
+1
10
SDA, IRQ—OUTPUT
Output High Current
Output Low Voltage
IOH
VOL
VOUT = 5.5V, TA = +25°C
VDVDD = 1.65V, IOL = 3mA
V
FA
pF
1
mA
0.2 x
DVDD
V
DIGMICDATA—INPUT
Input High Voltage
VIH
Input Low Voltage
VIL
0.65 x
DVDD
0.35 x
DVDD
Input Hysteresis
125
Input Leakage Current
Input Capacitance
V
IIH, IIL
VDVDD = 2.0V, VIN = 0V, 2.0V; TA = +25°C
-25
mV
+25
10
V
FA
pF
���������������������������������������������������������������� Maxim Integrated Products 20
MAX98088
Stereo Audio Codec
with FlexSound Technology
DIGITAL INPUT/OUTPUT CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V, TA = +25NC, unless otherwise noted.)
(Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
0.4
V
DIGMICCLK—OUTPUT
Output Low Voltage
VOL
VDVDD = 1.65V, IOL = 1mA
Output High Voltage
VOH
VDVDD = 1.65V, IOH = 1mA
DVDD 0.4
V
INPUT CLOCK CHARACTERISTICS
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V, TA = +25NC, unless otherwise noted.)
(Note 1)
PARAMETER
MCLK Input Frequency
MCLK Input Duty Cycle
SYMBOL
CONDITIONS
fMCLK
MIN
DAI1 LRCLK Average Frequency
Error (Note 9)
MHz
PSCLK = 10 or 11
30
60
DHF_ = 0
8
48
DHF_ = 1
48
96
70
100
FREQ1 = 0x8 to 0xF
FREQ1 = 0x0
0
0
+0.025
-0.025
+0.025
Rapid lock mode
2
7
Nonrapid lock mode
12
25
100
10
%
psRMS
-0.025
Maximum LRCLK Jitter to Maintain
PLL Lock
Soft-Start/Stop Time
UNITS
60
40
DAI2 LRCLK Average Frequency
Error (Note 9)
PLL Lock Time
50
MAX
PSCLK = 01
Maximum MCLK Input Jitter
LRCLK Sample Rate (Note 8)
TYP
10
kHz
%
%
ms
ns
ms
���������������������������������������������������������������� Maxim Integrated Products 21
MAX98088
Stereo Audio Codec
with FlexSound Technology
AUDIO INTERFACE TIMING CHARACTERISTICS
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V, TA = +25NC, unless otherwise noted.)
(Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
BCLK Cycle Time
tBCLK
Slave mode
90
ns
BCLK High Time
tBCLKH
Slave mode
20
ns
BCLK Low Time
tBCLKL
Slave mode
20
BCLK or LRCLK Rise and Fall Time
SDIN to BCLK Setup Time
tR, tF
5
tSETUP
LRCLK to BCLK Setup Time
tSYNCSET
SDIN to BCLK Hold Time
Slave mode
tHOLD
LRCLK to BCLK Hold Time
tSYNCHOLD Slave mode Minimum Delay Time from LSB
BCLK Falling Edge to
High-Impedance State
tHIZOUT
Master mode, TDM_ = 1
LRCLK Rising Edge to SDOUT
MSB Delay
tSYNCTX
CL = 30pF, TDM_ = 1, FSW_ = 1
BCLK to SDOUT Delay
tCLKTX
Delay Time from BCLK to LRCLK
Delay Time from LRCLK to BCLK
After LSB
CL = 30pF
tCLKSYNC
tENDSYNC
Master
mode
Master
mode
ns
20
ns
20
ns
20
ns
20
ns
42
ns
50
TDM_ = 1, BCLK rising edge
50
TDM_ = 0
50
TDM_ = 1
-15
ns
ns
+15
0.8 x
TDM_ = 0
ns
tBCLKL
TDM_ = 1, FSW_ = 1
20
ns
tBCLK
tF
t
BCLK R
(OUTPUT)
ns
Master mode, CL = 15pF
tBCLKH
BCLK
(INPUT)
tCLKSYNC
tBCLKL
tSYNCSET
LRCLK
(INPUT)
LRCLK
(OUTPUT)
tCLKTX
tHIZOUT
SDOUT
(OUTPUT)
LSB
SDIN
(INPUT)
LSB
tCLKTX
tHIZOUT
HI-Z
tSETUP
MSB
tHOLD
MSB
MASTER MODE
SDOUT
(OUTPUT)
LSB
SDIN
(INPUT)
LSB
HI-Z
tSETUP
MSB
tHOLD
MSB
SLAVE MODE
Figure 1. Non-TDM Audio Interface Timing Diagrams (TDM_ = 0)
���������������������������������������������������������������� Maxim Integrated Products 22
MAX98088
Stereo Audio Codec
with FlexSound Technology
tBCLK
tF
tR
tBCLKH
BCLK (OUTPUT)
tBCLKL
BCLK (INPUT)
tCLKSYNC
tSYNCSET
tCLKSYNC
LRCLK (OUTPUT)
tSYNCHOLD
LRCLK (INPUT)
tCLKTX
tHIZOUT
SDOUT (OUTPUT)
LSB
SDOUT (OUTPUT)
MSB
HI-Z
tCLKTX
tHIZOUT
LSB
HI-Z
MSB
tSETUP tHOLD
SDIN (INPUT)
LSB
tSETUP tHOLD
SDIN (INPUT)
MSB
LSB
MSB
MASTER MODE
SLAVE MODE
Figure 2. TDM Audio Interface Timing Diagram (TDM_ = 1, FSW_ = 0)
tBCLK
tF
tR
tBCLKH
BCLK (OUTPUT)
tENDSYNC
tCLKSYNC
LRCLK (OUTPUT)
LRCLK (INPUT)
tHIZOUT
SDOUT (OUTPUT)
tBCLKL
BCLK (INPUT)
LSB
tSYNCTX
tCLKTX
HI-Z
MSB
tHIZOUT
SDOUT (OUTPUT)
LSB
tSYNCTX
tCLKTX
HI-Z
MSB
tSETUP tHOLD
SDIN (INPUT)
LSB
tSETUP tHOLD
SDIN (INPUT)
MSB
MASTER MODE
LSB
MSB
SLAVE MODE
Figure 3. TDM Audio Interface Timing Diagram (TDM_ = 1, FSW_ = 1)
DIGITAL MICROPHONE TIMING CHARACTERSTICS
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V, TA = +25NC, unless otherwise noted.)
(Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MICCLK = 00
MCLK/8
MICCLK = 01
MCLK/6
MAX
UNITS
DIGMICCLK Frequency
fMICCLK
MHz
DIGMICDATA to DIGMICCLK
Setup Time
tSU,MIC
Either clock edge
20
ns
DIGMICDATA to DIGMICCLK
Hold Time
tHD,MIC
Either clock edge
0
ns
���������������������������������������������������������������� Maxim Integrated Products 23
MAX98088
Stereo Audio Codec
with FlexSound Technology
1/fMICCLK
tHD,MIC tSU,MIC
tHD,MIC tSU,MIC
LEFT
RIGHT
LEFT
RIGHT
Figure 4. Digital Microphone Timing Diagram
I2C TIMING CHARACTERSTICS
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V, TA = +25NC, unless otherwise noted.)
(Note 1)
PARAMETER
SYMBOL
CONDITIONS
Guaranteed by SCL pulse-width low and
high
MIN
MAX
UNITS
400
kHz
Serial-Clock Frequency
fSCL
Bus Free Time Between STOP and
START Conditions
tBUF
1.3
Fs
tHD,STA
0.6
Fs
SCL Pulse-Width Low
tLOW
1.3
Fs
SCL Pulse-Width High
Hold Time (Repeated) START
Condition
0
TYP
tHIGH
0.6
Fs
Setup Time for a Repeated START
Condition
tSU,STA
0.6
Fs
Data Hold Time
Data Setup Time
tHD,DAT
tSU,DAT
RPU = 475I, CB = 100pF, 400pF
0
100
900
ns
ns
SDA and SCL Receiving Rise Time
tR
(Note 10)
20 +
0.1CB
300
ns
SDA and SCL Receiving Fall Time
tF
(Note 10)
20 +
0.1CB
300
ns
SDA Transmitting Fall Time
tF
RPU = 475I, CB = 100pF, 400pF (Note 10)
20 +
0.05CB
250
ns
400
pF
50
ns
Setup Time for STOP Condition
tSU,STO
Bus Capacitance
CB
Pulse Width of Suppressed Spike
tSP
0.6
Guaranteed by SDA transmitting fall time
0
Fs
���������������������������������������������������������������� Maxim Integrated Products 24
MAX98088
Stereo Audio Codec
with FlexSound Technology
I2C TIMING CHARACTERISTICS (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. TA = +25NC, unless otherwise noted.)
(Note 1)
SDA
tBUF
tSU,STA
tSU,DAT
tLOW
tHD,STA
tHD,DAT
tSP
tSU,STO
tHIGH
SCL
tHD,STA
tR
tF
START CONDITION
REPEATED START CONDITION
STOP
CONDITION
START
CONDITION
Figure 5. I2C Interface Timing Diagram
Note 1: The IC is 100% production tested at TA = +25NC. Specifications over temperature limits are guaranteed by design.
Note 2: Analog supply current = IAVDD + IHPVDD. Speaker supply current = ISPKLVDD + ISPKRVDD. Digital supply current = IDVDD
+ IDVDDS1 + IDVDDS2.
Note 3: Clocking all zeros into the DAC.
Note 4: Dynamic range measured using the EIAJ method. -60dBFS, 1kHz output signal, A-weighted and normalized to 0dBFS.
f = 20Hz to 20kHz.
Note 5: Gain measured relative to the 0dB setting.
Note 6: The filter specification is accurate only for synchronous clocking modes, where NI is a multiple of 0x1000.
Note 7: 0dBFS for DAC input. 1VP-P for INA/INB inputs.
Note 8: LRCLK may be any rate in the indicated range. Asynchronous or noninteger MCLK/LRCLK ratios may exhibit some fullscale performance degradation compared to synchronous integer related MCLK/LRCLK ratios.
Note 9: In master-mode operation, the accuracy of the MCLK input proportionally determines the accuracy of the sample clock rate.
Note 10: CB is in pF.
Power Consumption
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = 1.8V, VSPKLVDD = VSPKRVDD = 3.7V)
IAVDD
(mA)
IPVDD
(mA)
ISPKVDD +
ISPKLVDD
(mA)
IDVDD
(mA)
IDVDDS1 +
IDVDDS2
(mA)
POWER
(mW)
DYNAMIC
RANGE (dB)
DAC Playback 48kHz Stereo HP
DAC ª HP
Low power mode, 24-bit, music filters, 256Fs
1.25
0.47
0.00
1.35
0.01
5.55
97
DAC Playback 48kHz Stereo HP
DAC ª HP
Low power mode, 24-bit, music filters, 256Fs, 0.1mW/channel,
RHP = 32I
1.25
1.81
0.00
1.56
0.01
8.32
97
MODE
PLAYBACK TO HEADPHONE ONLY
���������������������������������������������������������������� Maxim Integrated Products 25
MAX98088
Stereo Audio Codec
with FlexSound Technology
Power Consumption (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = 1.8V, VSPKLVDD = VSPKRVDD = 3.7V)
IAVDD
(mA)
IPVDD
(mA)
ISPKVDD +
ISPKLVDD
(mA)
IDVDD
(mA)
IDVDDS1 +
IDVDDS2
(mA)
POWER
(mW)
DYNAMIC
RANGE (dB)
DAC Playback 48kHz Stereo HP
DAC ª HP
24-bit, music filters, 256Fs
2.04
1.27
0.00
1.53
0.01
8.72
101
DAC Playback 48kHz Stereo HP
DAC ª HP
24-bit, music filters, 256Fs, 0.1mW/
channel, RHP = 32I
2.04
2.11
0.00
1.74
0.01
10.63
101
DAC Playback 44.1kHz Stereo HP
DAC ª HP
24-bit, music filters
2.03
1.27
0.00
1.41
0.01
8.46
100
DAC Playback 44.1kHz Stereo HP
DAC ª HP
Low power mode, 24-bit, music
filters
1.25
0.47
0.00
1.25
0.01
5.34
97
DAC Playback 8kHz Stereo HP
DAC ª HP
16-bit, voice filters
2.04
1.27
0.00
1.07
0.00
7.89
95
DAC Playback 8kHz Stereo HP
DAC ª HP
16-bit, low power mode, voice filters
1.26
0.47
0.00
0.90
0.00
4.72
94
DAC Playback 8kHz Mono HP
DAC ª HP
16-bit, low power mode, voice filters
0.77
0.29
0.00
0.79
0.00
3.33
93.7
Line Playback Stereo HP
INA ª HP
Single-ended inputs
2.40
1.27
0.00
0.02
0.00
6.67
95
0.00
6.33
2.14
0.01
31.44
86
MODE
DAC PLAYBACK TO CLASS D SPEAKER
DAC Playback 48kHz Stereo SPK
DAC ª SPK
24-bit, music filters
2.31
���������������������������������������������������������������� Maxim Integrated Products 26
MAX98088
Stereo Audio Codec
with FlexSound Technology
Power Consumption (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = 1.8V, VSPKLVDD = VSPKRVDD = 3.7V)
IAVDD
(mA)
IPVDD
(mA)
ISPKVDD +
ISPKLVDD
(mA)
IDVDD
(mA)
IDVDDS1 +
IDVDDS2
(mA)
POWER
(mW)
DYNAMIC
RANGE (dB)
DAC Playback 48kHz Mono SPK
DAC ª SPK
24-bit, music filters
1.35
0.00
3.23
1.84
0.01
17.69
86
Line Playback Mono SPK
INA ª SPKL
Differential inputs
1.01
0.00
3.24
0.03
0.00
13.83
83
Full-Duplex 8kHz Mono RCV
MIC1 ª ADC
DAC ª REC
16-bit, voice filters
6.32
0.00
1.54
1.24
0.01
19.33
Record = 87
Playback = 94
Full-Duplex 8kHz Stereo HP
MIC1/2 ª ADC
DAC ª HP
16-bit, mixer, voice filters
11.19
1.27
0.48
1.28
0.01
26.43
Record = 87
Playback = 96
Full-Duplex 8kHz Stereo HP
MIC1/2 ª ADC
DAC ª HP
16-bit, low power mode, voice filters
7.12
0.47
0.48
1.10
0.02
17.44
Record = 87
Playback = 94
Line Stereo Record 48kHz
INA ª ADC
24-bit, low power, music filters
6.19
0.00
0.20
1.31
0.15
14.47
91
Line Stereo Record 48kHz
INA ª ADC
Direct pin input, 24bit, low power,
music filters
5.69
0.00
0.20
1.31
0.12
13.53
93
MODE
FULL DUPLEX
LINE RECORD
���������������������������������������������������������������� Maxim Integrated Products 27
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
Microphone to ADC
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY (MIC TO ADC)
-50
-60
-70
MAX98088 toc02
-40
-50
-60
-30
-40
-50
-60
-70
-80
-70
-90
-80
-90
-100
-90
-100
10
100
1000
1000
10,000
100,000
10
1000
10,000
100,000
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY (MIC TO ADC)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY (MIC TO ADC)
-60
-70
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
VIN = 0.1VP-P
AVMICPRE_ = 0dB
-10
-20
-30
-40
0
-50
-60
-70
-20
-30
-40
-50
-60
-70
-80
-90
-90
-90
-100
-100
-100
1000
FREQUENCY (Hz)
10,000
100,000
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
VIN = 0.032VP-P
AVMICPRE_ = 0dB
-10
-80
100
MAX98088 toc06
0
MAX98088 toc04
-50
10
100
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY (MIC TO ADC)
THD+N RATIO (dB)
-40
100
FREQUENCY (Hz)
THD+N RATIO (dB)
-30
10
FREQUENCY (Hz)
MCLK = 12.288MHz
LRCLK = 96kHz
NI MODE
VIN = 1VP-P
AVMICPRE_ = 0dB
-20
10,000
-80
FREQUENCY (Hz)
0
-10
THD+N RATIO (dB)
-30
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
VIN = 1VP-P
AVMICPRE_ = 0dB
-20
THD+N RATIO (dB)
-40
-20
0
-10
MAX98088 toc05
THD+N RATIO (dB)
-30
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
VIN = 1VP-P
AVMICPRE_ = 0dB
-10
THD+N RATIO (dB)
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
VIN = 1VP-P
AVMICPRE_ = 0dB
-20
0
MAX98088 toc01
0
-10
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY (MIC TO ADC)
MAX98088 toc03
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY (MIC TO ADC)
-80
10
100
1000
FREQUENCY (Hz)
10,000
10
100
1000
10,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 28
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
MODE = 0
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
VIN = 1VP-P
AVMICPRE_ = 0dB
-60
-70
-80
40
MICPRE = 0dB
30
0
10
100
1000
10
10k
-40
1000
10,000
-60
-80
-100
-120
-40
-100
-120
-160
-160
500 1000 1500 2000 2500 3000 3500 4000
1000
10,000
100,000
20
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
AVMICPRE_ = 0dB
0
-20
-40
-60
-80
-100
-120
-140
-180
-180
FREQUENCY (Hz)
100
FFT, 0dBFS (MIC TO ADC)
-80
-140
0
10
FREQUENCY (Hz)
-60
-140
MAX98088 toc09
-90
100,000
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
AVMICPRE_ = 0dB
-20
AMPLITUDE (dBFS)
AMPLITUDE (dBFS)
-20
0
MAX98088 toc10
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
AVMICPRE_ = 0dB
100
RIPPLE ON SPKLVDD,
SPKRVDD
-80
FFT, -60dBFS (MIC TO ADC)
FFT, 0dBFS (MIC TO ADC)
0
RIPPLE ON AVDD,
DVDD, HPVDD
-50
FREQUENCY (Hz)
FREQUENCY (Hz)
20
-40
-70
MCLK = 12.288MHz
LRCLK = 48kHz
FREQ MODE
10
-90
-30
-60
20
AMPLITUDE (dBFS)
-50
-20
MAX98088 toc11
-40
-10
MAX98088 toc12
-30
INPUTS AC GROUNDED
VRIPPLE = 200mVP-P
0
MICPRE = 20dB
50
-20
10
PSRR (dB)
MODE = 1
60
CMRR (dB)
NORMALIZED GAIN (dB)
-10
MICPRE = 30dB
MAX98088 toc08
0
70
MAX98088 toc07
10
POWER-SUPPLY RECTION RATIO
vs. FREQUENCY (MIC TO ADC)
COMMON-MODE REJECTION RATIO
vs. FREQUENCY (MIC TO ADC)
GAIN vs. FREQUENCY (MIC TO ADC)
0
500 1000 1500 2000 2500 3000 3500 4000
FREQUENCY (Hz)
0
5000
10,000
15,000
20,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 29
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
-60
-80
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
AVMICPRE_ = 0dB
0
-20
AMPLITUDE (dBFS)
-100
-40
-60
-80
-100
-120
-120
-140
-140
0
5
10
15
20
0
5
FREQUENCY (kHz)
FFT, -60dBFS (MIC TO ADC)
AMPLITUDE (dBFS)
20
FFT, 0dBFS (MIC TO ADC)
-60
-80
-100
MCLK = 12.288MHz
LRCLK = 96kHz
NI MODE
AVMICPRE_ = 0dB
0
-20
AMPLITUDE (dBFS)
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
AVMICPRE_ = 0dB
-40
15
20
MAX98088 toc15
0
-20
1
FREQUENCY (kHz)
MAX98088 toc16
AMPLITUDE (dBFS)
-40
MAX98088 toc13
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
AVMICPRE_ = 0dB
-20
FFT, 0dBFS (MIC TO ADC)
20
MAX98088 toc14
FFT, -60dBFS (MIC TO ADC)
0
-40
-60
-80
-100
-120
-120
-140
-140
0
5
10
FREQUENCY (kHz)
15
20
0
5
10
15
20
FREQUENCY (kHz)
���������������������������������������������������������������� Maxim Integrated Products 30
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
ADC ENABLE/DISABLE RESPONSE
(MIC TO ADC)
FFT, -60dBFS (MIC TO ADC)
MCLK = 12.288MHz
LRCLK = 96kHz
NI MODE
AVMICPRE_ = 0dB
AMPLITUDE (dBFS)
-20
-40
MAX98088 toc18
MAX98088 toc17
0
SCL
1V/div
-60
-80
ADC
OUTPUT
0.5V/div
-100
-120
-140
0
5
10
15
10ms/div
20
FREQUENCY (kHz)
SOFTWARE TURN-ON/OFF RESPONSE
(MIC TO ADC)
MAX98088 toc19
SCL
1V/div
ADC
OUTPUT
0.5V/div
10ms/div
���������������������������������������������������������������� Maxim Integrated Products 31
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
Line to ADC
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (LINE TO ADC)
-40
-50
-60
-70
-30
-40
-50
-60
-70
-20
-30
-40
-50
-60
-70
-80
-80
-90
-80
-90
-100
-90
100
1000
10,000
10
100,000
100
FREQUENCY (Hz)
1000
MCLK = 12.288MHz
LRCLK = 48kHz
VIN = 1VRMS
EXTERNAL GAIN MODE
RIN = 56kI
CIN = 1µF
-20
-30
-40
-50
-60
10,000
100,000
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (LINE-IN TO ADC)
10
VRIPPLE = 200mVP-P
0
-10
-20
PSRR (dB)
0
1000
FREQUENCY (Hz)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (LINE-IN TO ADC)
-10
100
10
100,000
10,000
FREQUENCY (Hz)
MAX98088 toc23
10
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
VIN = 0.1VP-P
AVPGAIN_ = +20dB
CIN = 1µF
-10
MAX98088 toc22
-20
0
MAX98088 toc24
-30
THD+N (dB)
THD+N RATIO (dB)
-20
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
VIN = 1VP-P
AVPGAIN_ = 0dB
CIN = 1µF
THD+N RATIO (dB)
-10
0
-10
THD+N RATIO (dB)
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
VIN = 1.4VP-P
AVPGAIN_ = -6dB
CIN = 1µF
MAX98088 toc20
0
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (LINE TO ADC)
MAX98088 toc21
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (LINE TO ADC)
-30
-40
RIPPLE ON AVDD,
DVDD, HPVDD
-50
-60
-70
-70
-80
-80
RIPPLE ON SPKLVDD,
SPKRVDD
-90
-90
10
100
1000
FREQUENCY (Hz)
10,000
100,000
10
100
1000
10,000
100,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 32
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
Line-In Pin Direct to ADC
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (LINE-IN DIRECT TO ADC)
-30
VRIPPLE = 200mVP-P
-20
-30
-40
PSRR (dB)
THD+N RATIO (dB)
-20
0
-10
MAX98088 toc26
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
VIN = 1VP-P
CIN = 1µF
MAX98088 toc25
0
-10
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (LINE-IN DIRECT TO ADC)
-50
-60
RIPPLE ON AVDD,
DVDD, HPVDD
-40
-50
-60
-70
-80
-70
-90
-80
-100
-90
10
100
1000
10,000
100,000
RIPPLE ON SPKLVDD, SPKRVDD
10
100
FREQUENCY (Hz)
1000
10,000
100,000
FREQUENCY (Hz)
Digital Loopback
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
-20
-60
-80
-100
-120
-140
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
-20
-40
AMPLITUDE (dBFS)
AMPLITUDE (dBFS)
-40
0
MAX98088 toc27
0
FFT, -60dBFS (SDINS1 TO SDINS2
DIGITAL LOOPBACK)
MAX98088 toc28
FFT, 0dBFS (SDINS1 TO SDINS2
DIGITAL LOOPBACK)
-60
-80
-100
-120
-140
-160
-160
-180
-180
0
5
10
FREQUENCY (kHz)
15
20
0
5
10
15
20
FREQUENCY (kHz)
���������������������������������������������������������������� Maxim Integrated Products 33
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
Analog Loopback
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
(LINE TO ADC TO DAC TO HEADPHONE)
-50
POUT = 0.020W
-70
-20
POUT = 0.020W
POUT = 0.01W
100
1000
100,000
-80
-120
10
100
-140
1000
10,000
0
100,000
5
10
15
FREQUENCY (Hz)
FREQUENCY (Hz)
FREQUENCY (kHz)
FFT, -60dBFS (LINE TO ADC TO DAC
TO HEADPHONE)
FFT, 0dBFS (LINE TO ADC TO DAC
TO HEADPHONE)
FFT, -60dBFS (LINE TO ADC TO DAC
TO HEADPHONE)
-40
-60
-80
-100
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
CIN = 1µF
0
-20
-40
-60
-80
-140
5
10
FREQUENCY (kHz)
15
20
-40
-60
-80
-120
-120
-140
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
CIN = 1µF
-20
20
-100
-100
-120
0
AMPLITUDE (dBV)
-20
20
MAX98088 toc33
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
RHP = 32I
CIN = 1µF
0
-60
-100
POUT = 0.01W
-80
10,000
AMPLITUDE (dBV)
10
-40
MAX98088 toc31
MAX98088 toc30
-50
-60
0
AMPLITUDE (dBV)
-40
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
RHP = 32I
CIN = 1µF
0
-70
-80
-90
-30
20
AMPLITUDE (dBV)
-40
-60
-20
MAX98088 toc32
THD+N RATIO (dB)
-30
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
CIN = 1µF
-10
THD+N RATIO (dB)
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
RHP = 32I
CIN = 1µF
-20
0
MAX98088 toc29
0
-10
FFT, 0dBFS (LINE TO ADC TO DAC
TO HEADPHONE)
MAX98088 toc34
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
(LINE TO ADC TO DAC TO HEADPHONE)
-140
0
5
10
FREQUENCY (kHz)
15
20
0
5
10
15
20
FREQUENCY (kHz)
���������������������������������������������������������������� Maxim Integrated Products 34
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
DAC to Receiver
f = 3000Hz
f = 1000Hz
-50
-60
-70
-70
0.04
0.06
0.08
2
140
100
THD+N = 1%
80
10
100
2.5
10,000
1000
3.0
3.5
4.0
4.5
5.0
5.5
SUPPLY VOLTAGE (V)
GAIN vs. FREQUENCY
(DAC TO RECEIVER)
POWER CONSUMPTION vs. OUTPUT
POWER (DAC TO RECEIVER)
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (DAC TO RECEIVER)
MAX98088 toc38
1
0
-1
-2
-3
250
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
AVREC = +8dB
RREC = 32I
200
150
0
INPUTS AC GROUNDED
VRIPPLE = 200mVP-P
-10
-20
-30
100
-40
RIPPLE ON AVDD,
DVDD, HPVDD
-50
-60
-70
50
RIPPLE ON SPKLVDD,
SPKRVDD
-80
-4
-90
-5
10
MAX98088 toc37
THD+N = 10%
120
FREQUENCY (Hz)
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RREC = 32I
3
160
60
-90
0.12
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RREC = 32I
AVREC = +8dB
180
OUTPUT POWER (W)
5
4
0.10
PSRR (dB)
0.02
POUT = 0.08W
200
MAX98088 toc39
0
POUT = 0.02W
-80
f = 100Hz
-90
NORMALIZED GAIN (dB)
-40
-60
-80
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RREC = 32I
AVREC = +8dB
OUTPUT POWER vs. SUPPLY VOLTAGE
(DAC TO RECEIVER)
OUTPUT POWER PER CHANNEL (mW)
-30
-40
-50
-20
POWER CONSUMPTION (mW)
THD+N (dB)
-30
THD+N (dB)
-20
-10
MAX98088 toc36
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RREC = 32I
AVREC = +8dB
-10
0
MAX98088 toc35
0
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (DAC TO RECEIVER)
100
1000
FREQUENCY (Hz)
10,000
MAX98088 toc40
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (DAC TO RECEIVER)
0
-100
0
20
40
60
80
100
OUTPUT POWER PER CHANNEL (mW)
120
10
100
1000
10,000
100,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 35
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
SOFTWARE TURN-ON/OFF RESPONSE
(DAC TO RECEIVER, VSEN = 1)
FFT, 0dBFS (DAC TO RECEIVER)
MAX98088 toc42
MAX98088 toc41
20
-20
AMPLITUDE (dBV)
RECEIVER
OUTPUT
1V/div
RECEIVER
OUTPUT
1V/div
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RREC = 32I
0
SCL
1V/div
SCL
1V/div
-40
MAX16067 toc43
SOFTWARE TURN-ON/OFF RESPONSE
(DAC TO RECEIVER, VSEN = 0)
-60
-80
-100
-120
-140
-160
0
10ms/div
10ms/div
5
10
20
15
FREQUENCY (kHz)
-40
-60
-80
-100
-20
-40
-60
-80
-100
-120
0
5
10
FREQUENCY (kHz)
15
20
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RREC = 32I
-20
-40
-60
-80
-100
-120
-140
0
MAX98088 toc45
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RREC = 32I
AMPLITUDE (dBm)
AMPLITUDE (dBV)
-20
0
MAX98088 toc44
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RREC = 32I
AMPLITUDE (dBm)
0
WIDEBAND FFT, 0dBFS
(DAC TO RECEIVER)
MAX98088 toc46
WIDEBAND FFT, 0dBFS
(DAC TO RECEIVER)
FFT, -60dBFS (DAC TO RECEIVER)
-120
0
1
10
100
FREQUENCY (kHz)
1000
10,000
0
1
10
100
1000
10,000
FREQUENCY (kHz)
���������������������������������������������������������������� Maxim Integrated Products 36
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
Line to Receiver
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (LINE TO RECEIVER)
-30
-40
f = 1000Hz
f = 6000Hz
-30
-40
POUT = 0.02W
-50
-60
-70
-60
POUT = 0.08W
-80
-70
0
0.02
0.04
0.06
0.08
10
100
1000
10,000
100,000
FREQUENCY (Hz)
GAIN vs. FREQUENCY
(LINE TO RECEIVER)
POWER-SUPPLY
REJECTION RATIO vs. FREQUENCY
(LINE-IN DIRECT TO RECEIVER)
0
MAX98088 toc49
RREC = 32I
CIN = 1µF
3
-90
0.10
OUTPUT POWER (W)
5
4
INPUTS AC GROUNDED
VRIPPLE = 200mVP-P
-10
-20
2
-30
1
PSRR (dB)
NORMALIZED GAIN (dB)
RREC = 32I
AVREC = +8dB
CIN = 1µF
0
-1
RIPPLE ON SPKLVDD,
SPKRVDD
-40
RIPPLE ON AVDD,
DVDD, HPVDD
-50
-60
-2
MAX98088 toc50
f = 100Hz
-50
-20
THD+N RATIO (dB)
THD+N RATIO (dB)
-20
-10
MAX98088 toc48
RREC = 32I
AVREC = +8dB
CIN = 1µF
-10
0
MAX98088 toc47
0
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (LINE TO RECEIVER)
-70
-3
-4
-80
-5
-90
10
100
1000
FREQUENCY (Hz)
10,000
100,000
10
100
1000
10,000
100,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 37
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
DAC to Line Output
FFT, 0dBFS (DAC TO LINE OUT)
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RLOAD = 10kI
-20
AMPLITUDE (dBV)
AMPLITUDE (dBV)
-20
MAX98088 toc51
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RLOAD = 10kI
0
0
-40
-60
-80
-40
MAX98088 toc52
FFT, -60dBFS (DAC TO LINE OUT)
20
-60
-80
-100
-100
-120
-120
-140
0
5
10
15
-140
20
0
5
FREQUENCY (kHz)
10
15
20
FREQUENCY (kHz)
Line to Line Output
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
(LINE-IN TO LINE-OUT)
-20
-20
-50
f = 6kHz
-60
-40
-50
-70
-80
-80
f = 1kHz
-90
0
0.2
0.4
0.6
VOUT = 0.2VRMS
-60
-70
f = 100Hz
0.8
1.0
OUTPUT LEVEL (VRMS)
1.4
-40
-50
-60
-70
-80
-90
VOUT = 0.8VRMS
-100
-90
1.2
VIN = 1VRMS, 1kHz
RLOAD = 10kI
EXTERNAL GAIN MODE
REXT = 56kI
-20
THD+N (dB)
THD+N (dB)
-40
0
-10
-30
-30
-30
THD+N (dB)
RLOAD = 10kI
-10
MAX98088 toc55
RLOAD = 10kI
-10
0
MAX98088 toc53
0
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (LINE-IN TO LINE-OUT)
MAX98088 toc54
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT LEVEL
(LINE-IN TO LINE-OUT)
10
100
1000
FREQUENCY (Hz)
10,000
100,000
10
100
1000
10,000
100,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 38
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
DAC to Speaker
-40
-20
f = 6000Hz
-50
-60
f = 1000Hz
-70
-30
-40
-50
f = 1000Hz
-60
-70
-80
0
0.2
0.4
0.6
0.8
1.0
f = 100Hz
-80
f = 100Hz
-90
1.2
-90
1.4
0
0.2
OUTPUT POWER (W)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
(DAC TO SPEAKER)
1
0
-1
-2
-20
-30
-40
-50
-70
-4
-80
-5
-90
100
1k
FREQUENCY (Hz)
10k
100k
f = 6000Hz
-60
-3
10
VSPK_VDD = 4.2V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSP_ = 4I + 33µH
AVSPK_ = +8dB
0
1.0
VSPK_VDD = 3.7V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSP_ = 4I + 33µH
AVSPK_ = +8dB
-10
-20
THD+N RATIO (dB)
2
0
-10
THD+N RATIO (dB)
NORMALIZED GAIN (dBrA)
3
0.8
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
(DAC TO SPEAKER)
MAX98088 toc59
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSPK_ = 8I + 68µH
4
0.6
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
(DAC TO SPEAKER)
MAX98088 toc58
5
0.4
OUTPUT POWER (W)
-30
f = 6000Hz
-40
-50
f = 1000Hz
-60
-70
f = 100Hz
f = 1000Hz
0
0.5
1.0
MAX98088 toc60
THD+N RATIO (dB)
-30
VSPK_VDD = 3.7V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSP_ = 8I + 68µH
AVSPK_ = +8dB
f = 6000Hz
-10
THD+N RATIO (dB)
VSPKVDD_ = 4.2V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSPK_ = 8I + 68µH
AVSPK_ = +8dB
-20
0
MAX98088 toc56
0
-10
MAX98088 toc57
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
(DAC TO SPEAKER)
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. OUTPUT POWER
(DAC TO SPEAKER)
f = 100Hz
-80
1.5
OUTPUT POWER (W)
2.0
2.5
0
0.5
1.0
1.5
2.0
OUTPUT POWER (W)
���������������������������������������������������������������� Maxim Integrated Products 39
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
f = 6000Hz
-40
-50
MAX98088 toc62
-40
-50
POUT = 0.55W
f = 100Hz
-20
-70
0
0.2
0.4
0.6
1.0
20
1.2
-40
-50
POUT = 0.55W
-70
POUT = 0.25W
-80
0.8
-30
-60
-70
f = 1000Hz
VSPK_VDD = 3.7V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSP_ = 8I + 68µH
AVSPK_ = +8dB
-10
-60
-60
200
2000
POUT = 0.25W
-80
20,000
20
200
2000
20,000
OUTPUT POWER (W)
FREQUENCY (Hz)
FREQUENCY (Hz)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
(DAC TO SPEAKER)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
(DAC TO SPEAKER)
OUTPUT POWER vs. SUPPLY VOLTAGE
(DAC TO SPEAKER)
-30
-40
POUT = 1W
-50
-60
-70
-20
-30
-40
POUT = 1W
-50
-60
POUT = 0.5W
-80
-90
100
1000
10,000
FREQUENCY (Hz)
100,000
2200
MAX98088 toc66
-10
-70
POUT = 0.5W
-80
VSPK_VDD = 3.7V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSP_ = 4I + 33µH
AVSPK_ = +8dB
OUTPUT POWER PER CHANNEL (mW)
-20
0
THD+N RATIO (dB)
VSPK_VDD = 4.2V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSP_ = 4I + 33µH
AVSPK_ = +8dB
MAX98088 toc64
0
-10
THD+N RATIO (dB)
-30
0
THD+N RATIO (dB)
-30
-20
MAX98088 toc65
THD+N RATIO (dB)
-20
VSPK_VDD = 4.2V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSP_ = 8I + 68µH
AVSPK_ = +8dB
-10
THD+N RATIO (dB)
VSPK_VDD = 3V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSP_ = 4I + 33µH
AVSPK_ = +8dB
-10
0
MAX98088 toc61
0
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
(DAC TO SPEAKER)
MAX98088 toc63
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
(DAC TO SPEAKER)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
(DAC TO SPEAKER)
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSPK_ = 8I + 68µH
AVSPK_ = +8dB
2000
1800
1600
1400
THD+N = 10%
1200
1000
800
THD+N = 1%
600
400
-90
100
1000
10,000
FREQUENCY (Hz)
100,000
2.5
3.0
3.5
4.0
4.5
5.0
5.5
SUPPLY VOLTAGE (V)
���������������������������������������������������������������� Maxim Integrated Products 40
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
GAIN vs. FREQUENCY
(DAC TO SPEAKER)
THD+N = 10%
2000
1500
THD+N = 1%
1000
MAX98088 toc68
80
1
0
-1
70
60
40
-2
30
-3
20
-4
10
0
-5
3.5
4.0
4.5
5.0
1k
10k
0.5
1.0
1.5
2.5
2.0
OUTPUT POWER (W)
EFFICIENCY vs. OUTPUT POWER
(DAC TO SPEAKER)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
(DAC TO SPEAKER)
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (DAC TO SPEAKER)
60
ZSPK = 4I + 33µH
40
VSPK_VDD = 3.7V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
AVSKP_ = +8dB
30
20
10
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSPK_ = 8I + 68µH
SPKVOL_ = +8dB
ALL ZEROS AT INPUT
15
12
9
0.4
0.6
0.8
1.0
OUTPUT POWER (W)
1.2
1.4
1.6
-20
-30
RIPPLE ON AVDD,
DVDD, HPVDD
-40
-60
RIPPLE ON SPKLVDD,
SPKRVDD
-70
0
0.2
VRIPPLE = 200mVP-P
-10
-50
6
3
0
0
MAX98088 toc71
18
PSRR (dB)
70
0
0
100k
FREQUENCY (Hz)
80
50
100
SUPPLY VOLTAGE (V)
ZSPK = 8I + 68µH
90
VSPK_VDD = 4.2V
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
AVSKP_ = +8dB
0
10
5.5
SUPPLY CURRENT (mA)
100
3.0
ZSPK = 4I + 33µH
50
500
2.5
EFFICIENCY (%)
2
ZSPK = 8I + 68µH
90
MAX98088 toc72
2500
3
100
EFFICIENCY (%)
3000
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSPK_ = 8I + 68µH
4
NORMALIZED GAIN (dB)
3500
5
MAX98088 toc67
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSPK_ = 4I + 33µH
AVSPK_ = +8dB
MAX98088 toc70
OUTPUT POWER PER CHANNEL (mW)
4000
EFFICIENCY vs. OUTPUT POWER
(DAC TO SPEAKER)
MAX98088 toc69
OUTPUT POWER vs. SUPPLY VOLTAGE
(DAC TO SPEAKER)
-80
2.5
3.0
3.5
4.0
4.5
SUPPLY VOLTAGE (V)
5.0
5.5
10
100
1000
10,000
100,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 41
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
SOFTWARE TURN-ON/OFF RESPONSE
(DAC TO SPEAKER, VSEN = 0)
CROSSTALK vs. FREQUENCY
(DAC TO SPEAKER)
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
ZSPK_ = 8I + 68µH
-20
CROSSTALK (dB)
MAX98088 toc73
0
-10
SOFTWARE TURN-ON/OFF RESPONSE
(DAC TO SPEAKER, VSEN = 1)
MAX98088 toc74
MAX98088 toc75
SCL
1V/div
SCL
1V/div
SPEAKER
OUTPUT
1V/div
SPEAKER
OUTPUT
1V/div
-30
-40
-50
-60
-70
-80
10
100
1000
10,000
10ms/div
100,000
10ms/div
FREQUENCY (Hz)
FFT, -60dBFS (DAC TO SPEAKERS)
-60
-80
-40
WIDEBAND FFT (DAC TO SPEAKER)
MAX98088 toc77
-60
-80
-100
-100
0
5000
10,000
FREQUENCY (kHz)
15,000
20,000
-20
-30
-40
-50
-60
-70
-90
-140
-140
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
ZSPK_ = 8I + 68µH
-10
-80
-120
-120
0
AMPLITUDE (dBm)
-40
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
ZSPK_ = 8I + 68µH
-20
AMPLITUDE (dBV)
-20
AMPLITUDE (dBV)
MAX98088 toc76
MCLK = 12.2888MHz
LRCLK = 48kHz
NI MODE
ZSPK_ = 8I + 68µH
0
0
MAX98088 toc78
FFT, -60dBFS (DAC TO SPEAKERS)
20
0
5000
10,000
FREQUENCY (kHz)
15,000
20,000
-100
1
10
100
FREQUENCY (MHz)
���������������������������������������������������������������� Maxim Integrated Products 42
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
Line to Speaker
f = 1000Hz
-50
-40
-70
-70
-80
0.2
0.4
MAX98088 toc80
POUT = 0.5W
0.8
1.0
100
1000
-2
10
100,000
10,000
100
FREQUENCY (Hz)
10
INPUTS AC GROUNDED
VRIPPLE = 200mVP-P
1000
0
ZFN = 8I + 68µH
CIN = 1µF
-10
-20
CROSSTALK (dB)
RIPPLE ON SPKLVDD,
SPKRVDD
-40
-50
-60
-80
100
1000
FREQUENCY (Hz)
10,000
-40
-50
RIGHT TO LEFT
-70
-90
10
-30
-60
RIPPLE ON AVDD,
DVDD, HPVDD
-70
100,000
CROSSTALK vs. FREQUENCY
(LINE TO SPEAKER)
-20
-30
10,000
FREQUENCY (Hz)
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (LINE-IN TO SPEAKER)
-10
0
-1
-5
10
OUTPUT POWER (W)
0
1
-4
-80
0.6
2
-3
POUT = 0.25W
MAX98088 toc82
0
3
-50
-60
ZFN = 8I + 68µH
CIN = 1µF
4
-30
-60
f = 100Hz
5
MAX98088 toc83
f = 6000Hz
-20
GAIN vs. FREQUENCY
(LINE TO SPEAKER)
NORMALIZED GAIN (dB)
-40
PSRR (dB)
THD+N RATIO (dB)
-30
ZSPK = 8I + 68µH
AVSPK_ = +8dB
CIN = 1µF
-10
THD+N RATIO (dB)
ZSPK = 8I + 68µH
AVSPK_ = +8dB
CIN = 1µF
-20
0
MAX98088 toc79
0
-10
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
(LINE TO SPEAKER)
MAX98088 toc81
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
(LINE TO SPEAKER)
100,000
LEFT TO RIGHT
-80
10
100
1000
10,000
100,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 43
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
DAC to Headphone
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (DAC TO HEADPHONE)
-40
-50
f = 3000Hz
-60
-70
0
0.01
-40
f = 6000Hz
-50
-60
f = 1000Hz
f = 100Hz
-80
f = 100Hz
-90
-30
-70
f = 1000Hz
-80
-90
0.02
0.03
0.04
0
0.05
0.01
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (DAC TO HEADPHONE)
-40
-50
-60
f = 6000Hz
-70
f = 1000Hz
-30
-50
-60
0.02
0.03
OUTPUT POWER (W)
0.04
0.05
f = 6000Hz
0.04
0.05
-20
-30
-40
-50
-60
f = 6000Hz
f = 1000Hz
-80
f = 100Hz
-90
0.01
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 16I
AVHP_ = +3dB
-10
-70
f = 1000Hz
0
0
MAX98088 toc87
-40
-80
f = 100Hz
-90
0.01
-20
-70
-80
0
MCLK = 12.288MHz
LRCLK = 96kHz
NI MODE
RHP = 32I
AVHP_ = +3dB
THD+N RATIO (dB)
-30
0
-10
THD+N RATIO (dB)
THD+N RATIO (dB)
-20
0.03
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (DAC TO HEADPHONE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (DAC TO HEADPHONE)
MAX98088 toc86
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
AVHP_ = +3dB
-10
0.02
OUTPUT POWER (W)
OUTPUT POWER (W)
0
MAX98088 toc85
-20
0.02
0.03
OUTPUT POWER (W)
f = 100Hz
-90
0.04
0.05
MAX98088 toc88
THD+N RATIO (dB)
-30
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
RHP = 32I
AVHP_ = +3dB
-10
THD+N RATIO (dB)
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RHP = 32I
AVHP_ = +3dB
-20
0
MAX98088 toc84
0
-10
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (DAC TO HEADPHONE)
0
0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08
OUTPUT POWER (W)
���������������������������������������������������������������� Maxim Integrated Products 44
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (DAC TO HEADPHONE)
-40
-50
f = 6000Hz
-60
-70
f = 1000Hz
-80
f = 100Hz
MAX98088 toc90
-40
-50
-60
-80
0.01
0.02
0.03
0.04
10
0.05
100
-30
-40
-50
-60
POUT = 0.01W
-70
-80
POUT = 0.02W
-90
0
-20
POUT = 0.01W
-70
-90
1000
POUT = 0.02W
-90
10
10,000
100
1000
10,000
100,000
FREQUENCY (Hz)
FREQUENCY (Hz)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (DAC TO HEADPHONE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (DAC TO HEADPHONE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (DAC TO HEADPHONE)
-30
-40
-50
-60
POUT = 0.02W
-70
-20
-30
-40
-50
-60
POUT = 0.02W
-70
-80
POUT = 0.01W
10
100
1000
FREQUENCY (Hz)
10,000
100,000
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 16I
AVHP_ = +3dB
-10
-20
-30
-40
-50
-60
POUT = 0.01W
-70
-80
-90
0
THD+N RATIO (dB)
-20
MCLK = 12.288MHz
LRCLK = 96kHz
NI MODE
RHP = 32I
AVHP_ = +3dB
-10
THD+N RATIO (dB)
-10
0
MAX98088 toc92
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
AVHP_ = +3dB
-90
MAX98088 toc94
OUTPUT POWER (W)
0
THD+N RATIO (dB)
-30
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
RHP = 32I
AVHP_ = +3dB
-10
THD+N RATIO (dB)
-30
-20
0
MAX98088 toc93
THD+N RATIO (dB)
-20
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RHP = 32I
AVHP_ = +3dB
-10
THD+N RATIO (dB)
MCLK = 12.288MHz
LRCLK = 48kHz
256 Fs MODE
LOW POWER MODE
RHP = 16I
AVHP_ = +3dB
-10
0
MAX98088 toc89
0
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (DAC TO HEADPHONE)
MAX98088 toc91
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (DAC TO HEADPHONE)
-80
POUT = 0.01W
POUT = 0.02W
-90
-100
10
100
1000
FREQUENCY (Hz)
10,000
100,000
10
100
1000
10,000
100,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 45
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
PVDD CURRENT vs. OUTPUT POWER
(DAC TO HEADPHONE)
GAIN vs. FREQUENCY
(DAC TO HEADPHONE)
-10
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
120
100
-20
MODE = 0
-30
-40
-50
-80
100
10
60
RPH = 16I
20
RPH = 32I
0
1000
10,000
0.01
100,000
PVDD CURRENT vs. OUTPUT POWER
(DAC TO HEADPHONE)
50
RPH = 16I
30
RIPPLE ON AVDD,
DVDD, HPVDD
-50
-60
RIPPLE ON SPKLVDD,
SPKRVDD
-80
10
RPH = 32I
0
0.01
0.1
1
10
OUTPUT POWER PER CHANNEL (mW)
100
VRIPPLE = 200mVP-P
LOW POWER MODE
-20
-30
-40
-70
20
100
0
-10
-30
60
40
VRIPPLE = 200mVP-P
-20
PSRR (dB)
IPVDD (mA)
70
0
-10
PSRR (dB)
80
MCLK = 12.288MHz
LRCLK = 48kHz
LOW POWER MODE
AVHP_ = +3dB
10
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (DAC TO HEADPHONE)
MAX98088 toc98
90
1
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (DAC TO HEADPHONE)
MAX98088 toc97
100
0.1
OUTPUT POWER PER CHANNEL (mW)
FREQUENCY (Hz)
MAX98088 toc99
-70
80
40
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RHP = 32I
-60
MAX98088 toc96
MODE = 1
IPVDD (mA)
NORMALIZED GAIN (dBrA)
0
140
MAX98088 toc95
10
-40
RIPPLE ON AVDD,
DVDD, HPVDD
-50
-60
RIPPLE ON SPKLVDD,
SPKRVDD
-70
-80
-90
-90
-100
-100
10
100
1000
FREQUENCY (Hz)
10,000
100,000
10
100
1000
10,000
100,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 46
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
CROSSTALK vs. FREQUENCY
(DAC TO HEADPHONE)
MAX98088 toc101
MAX98088 toc100
0
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
-10
-20
CROSSTALK (dB)
SOFTWARE TURN-ON/OFF RESPONSE
(DAC TO HEADPHONE, VSEN = 0)
-30
SCL
1V/div
-40
-50
-60
RIGHT TO LEFT
-70
HEADPHONE
OUTPUT
1V/div
-80
-90
LEFT TO RIGHT
-100
10
100
1000
10,000
100,000
10ms/div
FREQUENCY (Hz)
SOFTWARE TURN-ON/OFF RESPONSE
(DAC TO HEADPHONE, VSEN = 1)
MAX98088 toc102
SCL
1V/div
HEADPHONE
OUTPUT
1V/div
10ms/div
���������������������������������������������������������������� Maxim Integrated Products 47
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
-80
-100
-120
-120
-140
5
10
15
20
-40
-60
-80
-100
-120
-140
0
5
FREQUENCY (kHz)
10
15
-140
20
0
5
FREQUENCY (kHz)
-40
15
20
FFT, 0dBFS (DAC TO HEADPHONE)
20
-60
-80
-100
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
0
-20
AMPLITUDE (dBV)
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
RHP = 32I
-20
10
FREQUENCY (kHz)
FFT, -60dBFS (DAC TO HEADPHONE)
0
MAX98088 toc106
0
MAX98088 toc105
-20
-60
-100
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
RHP = 32I
0
MAX98088 toc107
-80
-40
FFT, 0dBFS (DAC TO HEADPHONE)
20
AMPLITUDE (dBV)
-60
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RHP = 32I
-20
AMPLITUDE (dBV)
-40
AMPLITUDE (dBV)
AMPLITUDE (dBV)
-20
MAX98088 toc103
MCLK = 13MHz
LRCLK = 8kHz
FREQ MODE
RHP = 32I
0
FFT, -60dBFS (DAC TO HEADPHONE)
0
MAX98088 toc104
FFT, 0dBFS (DAC TO HEADPHONE)
20
-40
-60
-80
-120
-100
-140
-120
-140
-160
0
5
10
FREQUENCY (kHz)
15
20
0
5
10
15
20
FREQUENCY (kHz)
���������������������������������������������������������������� Maxim Integrated Products 48
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
FFT, -60dBFS (DAC TO HEADPHONE)
-60
-80
-100
-40
-60
-80
-120
-100
-140
-120
-160
0
5
10
15
-140
20
0
5
FREQUENCY (kHz)
FFT, -60dBFS (DAC TO HEADPHONE)
-100
-40
-60
-80
-100
-120
-120
-140
-140
-160
10
FREQUENCY (kHz)
15
20
MCLK = 12.288MHz
LRCLK = 48kHz
LOW POWER MODE
RHP = 32I
-20
AMPLITUDE (dBV)
AMPLITUDE (dBV)
-80
5
20
FFT, -60dBFS (DAC TO HEADPHONE)
-60
0
15
0
MAX98088 toc110
MCLK = 12.288MHz
LRCLK = 96kHz
NI MODE
RHP = 32I
-40
10
FREQUENCY (kHz)
0
-20
MAX98088 toc109
-20
MAX98088 toc111
AMPLITUDE (dBV)
-40
MCLK = 12.288MHz
LRCLK = 96kHz
NI MODE
RHP = 32I
0
AMPLITUDE (dBV)
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
-20
FFT, 0dBFS (DAC TO HEADPHONE)
20
MAX98088 toc108
0
-160
0
5
10
15
20
FREQUENCY (kHz)
���������������������������������������������������������������� Maxim Integrated Products 49
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
-40
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
RHP = 32I
-20
-60
-80
-100
-40
-60
-80
-100
-120
-120
-140
5
10
15
0
20
1
-80
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
LOW POWER MODE
-20
-40
-60
-80
-100
-100
0.1
1
10
100
FREQUENCY (kHz)
1000
10,000
MCLK = 12.288MHz
LRCLK = 48kHz
NI MODE
RHP = 32I
LOW POWER MODE
-20
-40
-60
-80
-100
-120
-120
0
MAX98088 toc115
OUTPUT AMPLITUDE (dBV)
-60
10,000
1000
WIDEBAND FFT -60dBFS
(DAC TO HEADPHONE)
0
OUTPUT AMPLITUDE (dBV)
MCLK = 13MHz
LRCLK = 44.1kHz
PLL MODE
RHP = 32I
MAX98088 toc114
0
-40
100
WIDEBAND FFT 0BFS
(DAC TO HEADPHONE)
WIDEBAND FFT -60dBFS
(DAC TO HEADPHONE)
-20
10
FREQUENCY (kHz)
FREQUENCY (kHz)
MAX98088 toc116
0
OFF-ISOLATION (dB)
AMPLITUDE (dBV)
-20
0
OUTPUT AMPLITUDE (dBV)
MCLK = 12.288MHz
LRCLK = 48kHz
LOW POWER MODE
RHP = 32I
MAX98088 toc112
0
MAX98088 toc113
WIDEBAND FFT 0BFS
(DAC TO HEADPHONE)
FFT, -60dBFS (DAC TO HEADPHONE)
0
1
10
100
FREQUENCY (kHz)
1000
10,000
-120
0.1
1
10
100
1000
10,000
FREQUENCY (kHz)
���������������������������������������������������������������� Maxim Integrated Products 50
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
Line to Headphone
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. OUTPUT POWER
(LINE TO HEADPHONE)
-20
-30
-40
-50
f = 100Hz
f = 6000Hz
-70
-80
-90
0.01
0.02
-40
-50
-60
POUT = 0.020W
-70
-80
f = 1000Hz
0
-30
-90
0.03
0.05
0.04
POUT = 0.01W
10
100
GAIN vs. FREQUENCY
(LINE TO HEADPHONE)
1
-40
-60
-70
-3
-80
-4
-90
10
100
1000
FREQUENCY (Hz)
10,000
100,000
RIPPLE ON AVDD,
DVDD, HPVDD
-50
-2
-5
100,000
0
RIPPLE ON SPKLVDD,
SPKRVDD
RHP = 32I
-10
-20
CROSSTALK (dB)
-30
0
VRIPPLE = 200mVP-P
-20
PSRR (dB)
NORMALIZED GAIN (dB)
0
-10
2
-1
10,000
CROSSTALK vs. FREQUENCY
(LINE TO HEADPHONES)
MAX98088 toc120
RHP = 32I
CIN = 1µF
3
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (LINE TO HEADPHONE)
MAX98088 toc119
5
4
1000
FREQUENCY (Hz)
OUTPUT POWER (W)
MAX98088 toc121
-60
RHP = 32I
AVHP_ = +3dB
CIN = 1µF
-10
THD+N RATIO (dB)
THD+N RATIO (dB)
-20
MAX98088 toc118
RHP = 32I
AVHP_ = +3dB
CIN = 1µF
-10
0
MAX98088 toc117
0
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
(LINE TO HEADPHONE)
-30
-40
-50
-60
-70
-80
-100
10
100
1000
FREQUENCY (Hz)
10,000
100,000
10
100
1000
10,000
100,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 51
MAX98088
Stereo Audio Codec
with FlexSound Technology
Typical Operating Characteristics (continued)
(VAVDD = VPVDD = VDVDD = VDVDDS1 = VDVDDS2 = +1.8V, VSPKLVDD = VSPKRVDD = 3.7V. Speaker loads (ZSPK) connected between
SPK_P and SPK_N. Receiver load (RREC) connected between RECP and RECN. Headphone loads (RHP) connected from HPL or HPR to
HPGND. RHP = J, RREC = J, ZSPK = J, CREF = 2.2FF, CMICBIAS = CREG = 1FF, CC1N-C1P = 1FF, CHPVDD = CHPVSS = 1FF. AVMICPRE_
= +20dB, AVMICPGA_ = 0dB, AVDACATTN = 0dB, AVDACGAIN = 0dB, AVADCLVL = 0dB, AVADCGAIN = 0dB, AVPGAIN_ = 0dB, AVHP_ =
0dB, AVREC = 0dB, AVSPK_ = 0dB, MCLK = 12.288MHz, LRCLK = 48kHz, MAS = 1. TA = +25NC, unless otherwise noted.)
Speaker Bypass Switch
90
AVPREGAIN = 20dB
80
0
MAX98088 toc122
100
-20
THD+N (dB)
AVPREGAIN = 0dB
50
40
30
10
f = 6000Hz
f = 1000kHz
-50
f = 100Hz
-70
-80
0
10
100
1000
0.05
0.10
0.15
0.20
OUTPUT POWER (W)
ON-RESISTANCE vs. VCOM
(SPEAKER BYPASS SWITCH)
OFF-ISOLATION vs. FREQUENCY
(SPEAKER BYPASS SWITCH)
2.5
VSPK_VDD = 3.7V
1.5
VSPK_VDD = 5.0V
VSPK_VDD = 4.2V
1.0
0
SPEAKER AMP DRIVING LOUDSPEAKER
SPEAKER BYPASS SWITCH OPEN
MEASURED AT RXIN_
-20
OFF-ISOLATION (dB)
VSPK_VDD = 3.0V
3.0
2.0
0
100,000
FREQUENCY (Hz)
ISW = 20mA
3.5
10,000
MAX98088 toc124
4.0
RON (I)
-40
-60
VOUT = -6dBV
CIN = 1µF
RHP = 32I
20
-30
0.25
MAX98088 toc125
CMRR (dB)
60
RECEIVER AMPLIFIER
DRIVING LOUDSPEAKER
ZSPK = 8I + 68µH
-10
70
MAX98088 toc123
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. OUTPUT POWER
(SPEAKER BYPASS SWITCH)
COMMON-MODE REJECTION RATIO
vs. FREQUENCY (LINE TO HEADPHONES)
-40
-60
50I LOAD ON RXIN_
-80
RECEIVER AMP DRIVING RXIN_
-100
0.5
0
0
1
2
3
VCOM (V)
4
5
6
-120
10
100
1000
10,000
100,000
FREQUENCY (Hz)
���������������������������������������������������������������� Maxim Integrated Products 52
MAX98088
Stereo Audio Codec
with FlexSound Technology
Pin Configuration
TOP VIEW
(BUMP SIDE DOWN)
1
2
3
4
5
6
7
8
9
A
SPKRN
SPKRGND
SPKLVDD
SPKLP
SPKLN
RECP/
LOUTL/
RXINP
PVDD
HPVSS
HPGND
B
SPKRN
SPKRGND
SPKLVDD
SPKLP
SPKLN
RECN/
LOUTR/
RXINN
C1P
C1N
HPVDD
C
SPKRP
SPKRP
SPKRVDD
SPKLGND
SPKLGND
N.C
N.C.
HPSNS
HPL
MAX98088
D
BCLKS1
SDOUTS1
SPKRVDD
LRCLKS1
N.C.
N.C.
N.C.
INB2
HPR
E
DVDDS1
MCLK
N.C.
SDINS1
IRQ
JACKSNS
INB1
MIC1P/
DIGMICDATA
INA2/
EXTMICN
F
DGND
BCLKS2
LRCLKS2
SDA
SCL
REG
MICBIAS
DIGMICCLK
INA1/
EXTMICP
G
SDOUTS2
DVDDS2
SDINS2
DVDD
AVDD
REF
AGND
MIC2N
MIC2P
MIC1N/
���������������������������������������������������������������� Maxim Integrated Products 53
MAX98088
Stereo Audio Codec
with FlexSound Technology
Pin Description
PIN
NAME
FUNCTION
A1, B1
SPKRN
A2, B2
SPKRGND
Negative Right-Channel Class D Speaker Output
Right-Speaker Ground
A3, B3
SPKLVDD
Left-Speaker, REF, Receiver Amp Power Supply. Bypass to SPKLGND with a 1FF and a
10FF capacitor.
A4, B4
SPKLP
Positive Left-Channel Class D Speaker Output
A5, B5
SPKLN
Negative Left-Channel Class D Speaker Output
A6
RECP/LOUTL/
RXINP
Positive Receiver Amplifier Output or Left Line Output. Can be positive bypass switch input
when receiver amp is shut down.
A7
PVDD
Headphone Power Supply. Bypass to HPGND with 1FF and 10FF capacitors.
A8
HPVSS
Inverting Charge-Pump Output. Bypass to HPGND with a 1FF ceramic capacitor.
A9
HPGND
Headphone Ground
B6
RECN/LOUTR/
RXINN
B7
C1P
Charge-Pump Flying Capacitor Positive Terminal. Connect a 1FF ceramic capacitor
between C1N and C1P.
B8
C1N
Charge-Pump Flying Capacitor Negative Terminal. Connect a 1FF ceramic capacitor
between C1N and C1P.
Negative Receiver Amplifier Output or Right Line Output. Can be negative bypass switch
input when receiver amp is shut down.
B9
HPVDD
Noninverting Charge-Pump Output. Bypass to HPGND with a 1FF ceramic capacitor.
C1, C2
SPKRP
Positive Right-Channel Class D Speaker Output
C3, D3
SPKRVDD
Right-Speaker Power Supply. Bypass to SPKRGND with a 1FF capacitor.
C4, C5
SPKLGND
Left-Speaker Ground
C6, C7, D5, D6,
D7, E3
N.C.
C8
HPSNS
C9
HPL
D1
BCLKS1
D2
SDOUTS1
S1 Digital Audio Serial-Data ADC Output. The output voltage is referenced to DVDDS1.
D4
LRCLKS1
S1 Digital Audio Left-Right Clock Input/Output. LRCLKS1 is the audio sample rate clock
and determines whether S1 audio data is routed to the left or right channel. In TDM mode,
LRCLKS1 is a frame sync pulse. LRCLKS1 is an input when the IC is in slave mode and an
output when in master mode.
D8
INB2
Single-Ended Line Input B2. Also positive differential line input B.
D9
HPR
Right-Channel Headphone Output
E1
DVDDS1
E2
MCLK
E4
SDINS1
No Connection
Headphone Amplifier Ground Sense. Connect to the headphone jack ground terminal or
connect to ground.
Left-Channel Headphone Output
S1 Digital Audio Bit Clock Input/Output. BCLKS1 is an input when the IC is in slave mode
and an output when in master mode. The input/output voltage is referenced to DVDDS1.
S1 Digital Audio Interface Power-Supply Input. Bypass to DGND with a 1FF capacitor.
Master Clock Input. Acceptable input frequency range is 10MHz to 60MHz.
S1 Digital Audio Serial-Data DAC Input. The input/output voltage is referenced to DVDDS1.
���������������������������������������������������������������� Maxim Integrated Products 54
MAX98088
Stereo Audio Codec
with FlexSound Technology
Pin Description (continued)
PIN
NAME
FUNCTION
E5
IRQ
Hardware Interrupt Output. IRQ can be programmed to pull low when bits in status register
0x00 change state. Read status register 0x00 to clear IRQ once set. Repeat faults have
no effect on IRQ until it is cleared by reading the I2C status register 0x00. Connect a 10kI
pullup resistor to DVDD for full output swing.
E6
JACKSNS
E7
INB1
E8
MIC1P/
DIGMICDATA
E9
INA2/
EXTMICN
F1
DGND
F2
BCLKS2
S2 Digital Audio Bit Clock Input/Output. BCLKS2 is an input when the IC is in slave mode
and an output when in master mode. The input/output voltage is referenced to DVDDS2.
F3
LRCLKS2
S2 Digital Audio Left-Right Clock Input/Output. LRCLKS2 is the audio sample rate clock
and determines whether audio data on S2 is routed to the left or right channel. In TDM
mode, LRCLKS2 is a frame sync pulse. LRCLKS2 is an input when the IC is in slave mode
and an output when in master mode. The input/output voltage is referenced to DVDDS2.
F4
SDA
I2C Serial-Data Input/Output. Connect a pullup resistor to DVDD for full output swing.
F5
SCL
I2C Serial-Clock Input. Connect a pullup resistor to DVDD for full output swing.
F6
REG
Common-Mode Voltage Reference. Bypass to AGND with a 1FF capacitor.
F7
MICBIAS
Low-Noise Bias Voltage. Outputs a 2.2V microphone bias. An external 2.2kI resistor
should be placed between MICBIAS and the microphone output.
F8
MIC1N/
DIGMICCLK
Negative Differential Microphone 1 Input. AC-couple a microphone with a series 1FF
capacitor. Can be retasked as a digital microphone clock output.
F9
INA1/
EXTMICP
Single-Ended Line Input A1. Also negative differential line input A or positive differential
external microphone input.
G1
SDOUTS2
S2 Digital Audio Serial-Data ADC Output. The output voltage is referenced to DVDDS2.
G2
DVDDS2
S2 Digital Audio Interface Power-Supply Input. Bypass to DGND with a 1FF capacitor.
G3
SDINS2
S2 Digital Audio Serial-Data DAC Input. The input voltage is referenced to DVDDS2.
G4
DVDD
Jack Sense. Detects the insertion of a jack. See the Jack Detection section.
Single-Ended Line Input B1. Also negative differential line input B.
Positive Differential Microphone 1 Input. AC-couple a microphone with a series 1FF capacitor. Can be retasked as a digital microphone data input.
Single-Ended Line Input A2. Also positive differential line input A or negative differential
external microphone input.
Digital Ground
Digital Power Supply. Supply for the digital core and I2C interface. Bypass to DGND with a
1FF capacitor.
G5
AVDD
Analog Power Supply. Bypass to AGND with a 1FF capacitor.
G6
REF
Converter Reference. Bypass to AGND with a 2.2FF capacitor.
G7
AGND
Analog Ground
G8
MIC2N
Negative Differential Microphone 2 Input. AC-couple a microphone with a series 1FF
capacitor.
G9
MIC2P
Positive Differential Microphone 2 Input. AC-couple a microphone with a series 1FF capacitor.
���������������������������������������������������������������� Maxim Integrated Products 55
MAX98088
Stereo Audio Codec
with FlexSound Technology
Detailed Description
The MAX98088 is a fully integrated stereo audio codec
with FlexSound technology and integrated amplifiers.
Two differential microphone amplifiers can accept signals
from three analog inputs. One input can be retasked to
support two digital microphones. Any combination of two
microphones (analog or digital) can be recorded simultaneously. The analog signals are amplified up to 50dB
and recorded by the stereo ADC. The digital record path
supports voice filtering with selectable preset highpass
filters and high stopband attenuation at fS/2. An automatic gain control (AGC) circuit monitors the digitized signal
and automatically adjusts the analog microphone gain
to make best use of the ADC’s dynamic range. A noise
gate attenuates signals below the user-defined threshold
to minimize the noise output by the ADC.
The IC includes two analog line inputs. One of the line
inputs can be optionally retasked as a third analog microphone input. Both line inputs support either stereo singleended input signals or mono differential signals. The line
inputs are preamplified and then routed to the ADC for
recording and/or to the output amplifiers for playback.
The single-ended line input signals from INA1 and INA2
can bypass the PGAs, and be connected directly to the
ADC input to provide the best dynamic range.
Integrated analog switches allow two differential microphone signals to be routed out the third microphone input
to an external device. This eliminates the need for an
external analog switch in systems that have two devices
recording signals from the same microphone.
Through two digital audio interfaces, the device can
transmit one stereo audio signal and receive two stereo
audio signals in a wide range of formats including I2S,
PCM, and up to four mono slots in TDM. Each interface
can be connected to either of two audio ports (S1 and
S2) for communication with external devices. Both audio
interfaces support 8kHz to 96kHz sample rates. Each
input signal is independently equalized using 5-band
parametric equalizers. A multiband automatic level control (ALC) boosts signals by up to 12dB. One signal path
additionally supports the same voiceband filtering as the
ADC path.
The IC includes a stereo Class D speaker amplifier, a
high-efficiency Class H stereo headphone amplifier, and
a differential receiver amplifier that can be configured as
a stereo single-ended line output.
When the receiver amplifier is disabled, analog switches
allow RECP/RXINP and RECN/RXINN to be reused for
signal routing. In systems where a single transducer is
used for both the loudspeaker and receiver, an external receiver amplifier can be routed to the left speaker
through RECP/RXINP and RECN/RXINN, bypassing the
Class D amplifier, to connect to the loudspeaker. If the
internal receiver amplifier is used, then leave RECP/
RXINP and RECN/RXINN unconnected. In systems
where an external amplifier drives both the receiver and
the MAX98088’s line input, one of the differential signals
can be disconnected from the receiver when not needed
by passing it through the analog switch that connects
RECP/RXINP to RECN/RXINN.
The stereo Class D amplifier provides efficient amplification for two speakers. The amplifier includes active emissions limiting to minimize the radiated emissions (EMI)
traditionally associated with Class D. In most systems,
no output filtering is required to meet standard EMI limits.
To optimize speaker sound quality, the IC includes an
excursion limiter, a distortion limiter, and a power limiter.
The excursion limiter is a dynamic highpass filter with
variable corner frequency that increases in response
to high signal levels. Low-frequency energy typically
causes more distortion than useful sound at high signal levels, so attenuating low frequencies allows the
speaker to play louder without distortion or damage. At
lower signal levels, the filter corner frequency reduces
to pass more low frequency energy when the speaker
can handle it. The distortion limiter reduces the volume
when the output signal exceeds a preset distortion level.
This ensures that regardless of input signal and battery
voltage, excessive distortion is never heard by the user.
The power limiter monitors the continuous power into the
loudspeaker and lowers the signal level if the speaker is
at risk of overheating.
The stereo Class H headphone amplifier uses a dualmode charge pump to maximize efficiency while outputting a ground-referenced signal. This eliminates the
need for DC-blocking capacitors or a midrail bias for the
headphone jack ground return. Ground sense reduces
output noise caused by ground return current.
The IC integrates jack detection allowing the detection of
insertion and removal of accessories.
���������������������������������������������������������������� Maxim Integrated Products 56
MAX98088
Stereo Audio Codec
with FlexSound Technology
I2C Slave Address
Configure the MAX98088 using the I2C control bus. The
IC uses a slave address of 0x20 or 00100000 for write
operations and 0x21 or 00100001 for read operations.
See the I2C Serial Interface section for a complete interface description.
Registers
Table 1 lists all of the registers, their addresses, and
power-on-reset states. Registers 0x00 to 0x03 and 0xFF
are read-only while all of the other registers are read/
write. Write zeros to all unused bits in the register table
when updating the register, unless otherwise noted.
Table 1. Register Map
REGISTER
STATUS
Status
B7
B6
B5
B4
B3
B2
B1
B0
CLD
SLD
ULK
—
—
—
JDET
—
Microphone
AGC/NG
NG
AGC
Jack Status
—
JKSNS
—
—
Battery
Voltage
—
—
—
Interrupt
Enable
ICLD
ISLD
IULK
—
—
—
—
VBAT
0
ADDRESS DEFAULT R/W PAGE
0x00
—
R
111
0x01
—
R
70
0x02
—
R
110
0x03
—
R/W
110
0
0
IJDET
0
0x0F
0x00
R/W
111
0
0
0
0
0x10
0x00
R/W
81
0x11
0x00
R/W 81, 82
0x12
0x00
R/W
82
NI1[0]
0x13
0x00
R/W
82
WS1
0x14
0x00
R/W
76
0x15
0x00
R/W
77
DMONO1 HIZOFF1 SDOEN1 SDIEN1
0x16
0x00
R/W 77, 78
SLOTDLY1
0x17
0x00
R/W
78
0x18
0x00
R/W
86
MASTER CLOCK CONTROL
Master Clock
0
0
PSCLK
DAI1 CLOCK CONTROL
Clock Mode
Any Clock
Control
SR1
FREQ1
PLL1
NI1[14:8]
NI1[7:1]
DAI1 CONFIGURATION
Format
BCI1
DLY1
0
ADC_OSR1
DAC_ORS1
0
0
I/O
Configuration
SEL1
LTEN1
LBEN1
Time-Division
Multiplex
SLOTL1
Clock
Filters
MAS1
WCI1
SLOTR1
MODE1
AVFLT1
TDM1
FSW1
BSEL1
DHF1
DVFLT1
DAI2 CLOCK CONTROL
Clock Mode
Any Clock
Control
SR2
0
PLL2
0
0
0
0x19
0x00
R/W
81
0x1A
0x00
R/W
82
NI2[0]
0x1B
0x00
R/W
82
WS2
0x1C
0x00
R/W
76
0x1D
0x00
R/W
77
0x1E
0x00
R/W 77, 78
NI2[14:8]
NI2[7:1]
DAI2 CONFIGURATION
Format
Clock
I/O
Configuration
MAS2
WCI2
BCI2
DLY2
0
0
DAC_
ORS2
0
0
0
LBEN2
0
SEL2
TDM2
FSW2
BSEL2
DMONO2 HIZOFF2 SDOEN2 SDIEN2
���������������������������������������������������������������� Maxim Integrated Products 57
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 1. Register Map (continued)
REGISTER
Time-Division
Multiplex
Filters
SRC
Sample Rate
Converter
B7
B6
B5
SLOTL2
B4
B3
SLOTR2
B2
B1
B0
SLOTDLY2
ADDRESS DEFAULT R/W PAGE
0x1F
0x00
R/W
78
0
0
0
0
DHF2
0
0
DCB2
0x20
0x00
R/W
86
0
0
0
SRMIX_
MODE
SRMIX_
ENL
SRMIX_
ENR
SRC_
ENL
SRC_
ENR
0x21
0x00
R/W
85
0x22
0x00
R/W
92
MIXERS
DAC Mixer
MIXDAL
MIXDAR
Left ADC
Mixer
MIXADL
0x23
0x00
R/W
69
Right ADC
Mixer
MIXADR
0x24
0x00
R/W
69
Left
Headphone
Amplifier
Mixer
MIXHPL
0x25
0x00
R/W
105
Right
Headphone
Amplifier
Mixer
MIXHPR
0x26
0x00
R/W
105
0x27
0x00
R/W
105
Headphone
Amplifier
Mixer Control
0
0
MIXHPR_ MIXHPL_
PATHSEL PATHSEL
MIXHPR_GAIN
MIXHPL_GAIN
Left Receiver
Amplifier
Mixer
MIXRECL
0x28
0x00
R/W
94
Right
Receiver
Amplifier
Mixer
MIXRECR
0x29
0x00
R/W
94
0x2A
0x00
R/W
94
Receiver
Amplifier
Mixer Control
LINE_
MODE
0
0
0
MIXRECR_GAIN
MIXRECL_GAIN
Left Speaker
Amplifier
Mixer
MIXSPL
0x2B
0x00
R/W
97
Right
Speaker
Amplifier
Mixer
MIXSPR
0x2C
0x00
R/W
97
0x2D
0x00
R/W
97
Speaker
Amplifier
Mixer Control
0
0
0
0
MIXSPR_GAIN
MIXSPL_GAIN
���������������������������������������������������������������� Maxim Integrated Products 58
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 1. Register Map (continued)
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
ADDRESS DEFAULT R/W PAGE
LEVEL CONTROL
Sidetone
DAI1
Playback
Level
DAI1
Playback
Level
DAI2
Playback
Level
DAI2
Playback
Level
Left ADC
Level
Right ADC
Level
Microphone
1 Input Level
Microphone
2 Input Level
INA Input
Level
INB Input
Level
DSTS
0
DVST
DV1G
0x2E
0x00
R/W
74
DV1
0x2F
0x00
R/W
91
DV1M
0
0
0
0
EQCLP1
DVEQ1
0x30
0x00
R/W
90
DV2M
0
0
0
DV2
0x31
0x00
R/W
91
0
0
0
EQCLP2
DVEQ2
0x32
0x00
R/W
90
0
0
AVLG
AVL
0x33
0x00
R/W
73
0
0
AVRG
AVR
0x34
0x00
R/W
73
0
PA1EN
PGAM1
0x35
0x00
R/W
66
0
PA2EN
PGAM2
0x36
0x00
R/W
66
0
INAEXT
0
0
0
PGAINA
0x37
0x00
R/W
68
0
INBEXT
0
0
0
PGAINB
0x38
0x00
R/W
68
Left
Headphone
Amplifier
Volume
Control
HPLM
0
0
HPVOLL
0x39
0x00
R/W
106
Right
Headphone
Amplifier
Volume
Control
HPRM
0
0
HPVOLR
0x3A
0x00
R/W
106
Left Receiver
Amplifier
RECLM
Volume
Control
0
0
RECVOLL
0x3B
0x00
R/W
95
Right
Receiver
Amplifier
Volume
Control
0
0
RECVOLR
0x3C
0x00
R/W
95
RECRM
���������������������������������������������������������������� Maxim Integrated Products 59
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 1. Register Map (continued)
REGISTER
B7
B6
B5
0
0
SPVOLL
0x3D
0x00
R/W
98
0
0
SPVOLR
0x3E
0x00
R/W
98
0x3F
0x00
R/W 70, 71
0x40
0x00
R/W
71
0x41
0x00
R/W
100
100
Left Speaker
Amplifier
SPLM
Volume
Control
Right
Speaker
Amplifier
SPRM
Volume
Control
MICROPHONE AGC
Configuration AGCSRC
B3
AGCRLS
Threshold
PWRTH
Power Limiter
Distortion
Limiter
CONFIGURATION
PWRT2
0
0
INADIFF INBDIFF
MICCLK
Level Control VS2EN
Bypass
INABYP
Switches
B0
AGCHLD
0
0
DHPLCF
DHPTH
0x42
0x00
R/W
ALCMB
ALCTH
0x43
0x00
R/W 89, 100
PWRK
0x44
0x00
R/W
101
0x45
0x00
R/W
102
PWRT1
0
DIGMICL DIGMICR
ADDRESS DEFAULT R/W PAGE
0
0
THDCLP
Microphone
B1
AGCTH
Power Limiter
Audio Input
B2
AGCATK
ANTH
SPEAKER SIGNAL PROCESSING
Excursion
0
DHPUCF
Limiter Filter
Excursion
Limiter
0
0
0
Threshold
ALC
ALCEN
ALCRLS
Jack
Detection
B4
0
0
0
THDT1
0x46
0x00
R/W
103
0
0
0
0
0x47
0x00
R/W
68
0
0
0x48
0x00
R/W
66
EQ1EN
0x49
0x00
R/W 90, 108
EXTMIC
VSEN
ZDEN
0
0
0
0
0
MIC2BYP
0
0
RECBYP SPKBYP
0x4A
0x00
R/W
67,
107
0
0
0
0
0
JDEB
0x4B
0x00
R/W
110
INAEN
INBEN
0
0
MBEN
0
HPLEN
HPREN
SPLEN
SPREN
BGEN SPREGEN VCMEN
BIASEN
JDETEN
EQ2EN
POWER MANAGEMENT Input Enable
Output
Enable
Top-Level
Bias Control
DAC Low
Power
Mode 1
DAC Low
Power
Mode 2
System
Shutdown
DAI2_DAC_LP
ADLEN
ADREN
0x4C
0x00
R/W
63
RECLEN RECREN DALEN
DAREN
0x4D
0x00
R/W
64
0
0x4E
0xF0
R/W
64
DAI1_DAC_LP
0x4F
0x00
R/W
83
0
0
0
0
0
0
0
DAC2_IP_ DAC1_IP_ CGM2_ CGM1_
DITH_EN DITH_EN
EN
EN
0x50
0x0F
R/W
83
SHDN
VBATEN
0
0
PERFMODE HPPLYBACK PWRSV8K PWRSV
0x51
0x00
R/W
63,
100
���������������������������������������������������������������� Maxim Integrated Products 60
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 1. Register Map (continued)
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
ADDRESS DEFAULT R/W PAGE
DSP COEFFICIENTS EQ Band 1
(DAI1/DAI2)
EQ Band 2
(DAI1/DAI2)
EQ Band 3
(DAI1/DAI2)
EQ Band 4
(DAI1/DAI2)
K_1[15:8]
0x52/0x84
0xXX
R/W
89
K_1[7:0]
0x53/0x85
0xXX
R/W
89
K1_1[15:8]
0x54/0x86
0xXX
R/W
89
K1_1[7:0]
0x55/0x87
0xXX
R/W
89
K2_1[15:8]
0x56/0x88
0xXX
R/W
89
K2_1[7:0]
0x57/0x89
0xXX
R/W
89
c1_1[15:8]
0x58/0x8A
0xXX
R/W
89
c1_1[7:0]
0x59/0x8B
0xXX
R/W
89
c2_1[15:8]
0x5A/0x8C
0xXX
R/W
89
c2_1[7:0]
0x5B/0x8D
0xXX
R/W
89
K_2[15:8]
0x5C/0x8E
0xXX
R/W
89
K_2[7:0]
0x5D/0x8F
0xXX
R/W
89
K1_2[15:8]
0x5E/0x90
0xXX
R/W
89
K1_2[7:0]
0x5F/0x91
0xXX
R/W
89
K2_2[15:8]
0x60/0x92
0xXX
R/W
89
K2_2[7:0]
0x61/0x93
0xXX
R/W
89
c1_2[15:8]
0x62/0x94
0xXX
R/W
89
c1_2[7:0]
0x63/0x95
0xXX
R/W
89
c2_2[15:8]
0x64/0x96
0xXX
R/W
89
c2_2[7:0]
0x65/0x97
0xXX
R/W
89
K_3[15:8]
0x66/0x98
0xXX
R/W
89
K_3[7:0]
0x67/0x99
0xXX
R/W
89
K1_3[15:8]
0x68/0x9A
0xXX
R/W
89
K1_3[7:0]
0x69/0x9B
0xXX
R/W
89
K2_3[15:8]
0x6A/0x9C
0xXX
R/W
89
K2_3[7:0]
0x6B/0x9D
0xXX
R/W
89
c1_3[15:8]
0x6C/0x9E
0xXX
R/W
89
c1_3[7:0]
0x6D/0x9F
0xXX
R/W
89
c2_3[15:8]
0x6E/0xAE
0xXX
R/W
89
c2_3[7:0]
0x6F/0xA1
0xXX
R/W
89
K_4[15:8]
0x70/0xA2
0xXX
R/W
89
K_4[7:0]
0x71/0xA3
0xXX
R/W
89
K1_4[15:8]
0x72/0xA4
0xXX
R/W
89
K1_4[7:0]
0x73/0xA5
0xXX
R/W
89
K2_4[15:8]
0x74/0xA6
0xXX
R/W
89
K2_4[7:0]
0x75/0xA7
0xXX
R/W
89
c1_4[15:8]
0x76/0xA8
0xXX
R/W
89
c1_4[7:0]
0x77/0xA9
0xXX
R/W
89
c2_4[15:8]
0x78/0xAA
0xXX
R/W
89
c2_4[7:0]
0x79/0xAB
0xXX
R/W
89
���������������������������������������������������������������� Maxim Integrated Products 61
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 1. Register Map (continued)
REGISTER
EQ Band 5
(DAI1/DAI2)
Excursion
Limiter
Biquad
(DAI1/DAI2)
B7
B6
B5
B4
B3
B2
B1
B0
ADDRESS DEFAULT R/W PAGE
K_5[15:8]
0x7A/0xAC
0xXX
R/W
89
K_5[7:0]
0x7B/0xAD
0xXX
R/W
89
K1_5[15:8]
0x7C/0xAE
0xXX
R/W
89
K1_5[7:0]
0x7D/0xAF
0xXX
R/W
89
K2_5[15:8]
0x7E/0xB0
0xXX
R/W
89
K2_5[7:0]
0x7F/0xB1
0xXX
R/W
89
c1_5[15:8]
0x80/0xB2
0xXX
R/W
89
c1_5[7:0]
0x81/0xB3
0xXX
R/W
89
c2_5[15:8]
0x82/0xB4
0xXX
R/W
89
c2_5[7:0]
0x83/0xB5
0xXX
R/W
89
a1[15:8]
0xB6/0xC0
0xXX
R/W
89
a1[7:0]
0xB7/0xC1
0xXX
R/W
89
a2[15:8]
0xB8/0xC2
0xXX
R/W
89
a2[7:0]
0xB9/0xC3
0xXX
R/W
89
b0[15:8]
0xBA/0xC4
0xXX
R/W
89
b0[7:0]
0xBB/0xC5
0xXX
R/W
89
b1[15:8]
0xBC/0xC6
0xXX
R/W
89
b1[7:0]
0xBD/0xC7
0xXX
R/W
89
b2[15:8]
0xBE/0xC8
0xXX
R/W
89
b2[7:0]
0xBF/0xC9
0xXX
R/W
89
REV
0xFF
0x40
R
112
REVISION ID
Rev ID
���������������������������������������������������������������� Maxim Integrated Products 62
MAX98088
Stereo Audio Codec
with FlexSound Technology
Power Management
The IC includes comprehensive power management to allow the disabling of all unused circuits, minimizing supply
current.
Table 2. Power Management Registers
REGISTER
0x51
BIT
NAME
DESCRIPTION
7
SHDN
Global Shutdown. Disables everything except the headset detection circuitry, which is
controlled separately.
0 = Device shutdown
1 = Device enabled
6
VBATEN
3
PERFMODE
Performance Mode. Selects DAC to headphone playback performance mode.
0 = High performance playback mode.
1 = Low power playback mode.
HPPLYBCK
Headphone Only Playback Mode. Configures System Bias Control register bits for low
power playback when using DAC to headphone playback path only. When enabled,
this bit overrides the System Bias Control register settings. When disabled, the System
Bias Control register is used to enable system bias blocks. Set both HPPLYBCK and
PERFMODE for lowest power consumption when using DAC to headphone playback
path only.
0 = Disabled
1 = Enabled
PWRSV8K
8kHz Power Save Mode. PWRSV8K configures the ADC for reduced power consumption when fS = 8kHz. PWRSV8K can be used in conjunction with PWRSV when fS = 8kHz
for more power savings.
0 = Normal, high-performance mode.
1 = Low power mode.
0
PWRSV
Power Save Mode. PWRSV configures the ADC for reduced power consumption for all
sample rates. PWRSV can be used in conjunction with PWRSV8K for more power savings.
0 = Normal, high-performance mode.
1 = Low power mode.
7
INAEN
Line Input A Enable
0 = Disabled
1 = Enabled
6
INBEN
Line Input B Enable
0 = Disabled
1 = Enabled
3
MBEN
Microphone Bias Enable
0 = Disabled
1 = Enabled
1
ADLEN
Left ADC Enable
0 = Disabled
1 = Enabled
0
ADREN
Right ADC Enable
0 = Disabled
1 = Enabled
2
1
0x4C
See the Battery Measurement section.
���������������������������������������������������������������� Maxim Integrated Products 63
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 2. Power Management Registers (continued)
REGISTER
BIT
NAME
7
HPLEN
Left Headphone Enable
0 = Disabled
1 = Enabled
6
HPREN
Right Headphone Enable
0 = Disabled
1 = Enabled
5
SPLEN
Left Speaker Enable
0 = Disabled
1 = Enabled
4
SPREN
Right Speaker Enable
0 = Disabled
1 = Enabled
0x4D
DESCRIPTION
3
RECLEN
Receiver/Left Line Output Enable. Use this bit to enable the differential receiver output
or left line output.
0 = Disabled
1 = Enabled
2
RECREN
Right Line Output Enable. Use this bit to enable the right line output.
0 = Disabled
1 = Enabled
1
DALEN
Left DAC Enable
0 = Disabled
1 = Enabled
0
DAREN
Right DAC Enable
0 = Disabled
1 = Enabled
7
6
BGEN
SPREGEN
0x4E
Bandgap Enable. Must be enabled for proper operation of 2.5V regulator and associated circuitry.
0 = Disabled
1 = Enabled
2.5V Regulator Enable. SPREGEN enables a 2.5V internal regulator required for
the ADC, speaker and receiver/line out amplifier. The 2.5V regulator is powered by
SPKLVDD.
0 = Disabled
1 = Enabled
5
VCMEN
Common-Mode Voltage Resistor String Enable. VCMEN enables the common mode
voltage for the input and output amplifiers in the codec.
0 = Disabled
1 = Enabled
4
BIASEN
Chip Bias Enable. BIASEN needs to be set for the codec amplifiers to be enabled.
0 = Disabled
1 = Enabled
���������������������������������������������������������������� Maxim Integrated Products 64
MAX98088
Stereo Audio Codec
with FlexSound Technology
Microphone Inputs
In systems where the codec is not the only device
recording microphone signals, connect microphones to
MIC2P/MIC2N and EXTMICP/EXTMICN. MIC1P/MIC1N
then become outputs that route the microphone signals
to an external device as needed. Two devices can then
record microphone signals without needing external
analog switches.
In the typical application, one microphone input is used
for the handset microphone and the other is used as an
accessory microphone. In systems using a background
noise microphone, INA can be retasked as another
microphone input.
Analog microphone signals are amplified by two stages
of gain and then routed to the ADCs. The first stage offers
selectable 0dB, 20dB, or 30dB settings. The second
stage is a programmable-gain amplifier (PGA) adjustable
from 0dB to 20dB in 1dB steps. To maximize the signalto-noise ratio, use the gain in the first stage whenever
possible. Zero-crossing detection is included on the PGA
to minimize zipper noise while making gain changes.
The device includes three differential microphone inputs
and a low-noise microphone bias for powering the microphones (Figure 6). One microphone input can also be configured as a digital microphone input accepting signals
from up to two digital microphones. Any two microphones,
analog or digital, can be recorded simultaneously.
MCLK
MICBIAS
REG
MBEN
CLOCK
CONTROL
MIC1P/
DIGMICDATA
PGAM1:
+20dB TO 0dB
MIC1N/
DIGMICCLK
AGC CONTROL
EXTMIC
PA1EN:
0/20/30dB
MIC2BYP
MIC2P
MIX
ADLEN
ADCL
MIC2N
EXTMIC
PA2EN:
0/20/30dB
PGAM1:
+20dB TO 0dB
MIXADL
INABYP
MIX
PGAINA:
+20dB TO -6dB
INA1/EXTMICP
ADCR
INADIFF
ADREN
MIXADR
INA2/EXTMICN
PGAINA:
+20dB TO -6dB
Figure 6. Microphone Input Block Diagram
���������������������������������������������������������������� Maxim Integrated Products 65
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 3. Microphone Input Registers
REGISTER
BIT
NAME
6
PA1EN/PA2EN
5
3
0x35/0x36
PGAM1/PGAM2
1
0
7
MICCLK
6
5
GAIN (dB)
VALUE
GAIN (dB)
0x00
0x01
+20
0x0B
+9
+19
0x0C
+8
0x02
+18
0x0D
+7
0x03
+17
0x0E
+6
0x04
+16
0x0F
+5
0x05
+15
0x10
+4
0x06
+14
0x11
+3
0x07
+13
0x12
+2
0x08
+12
0x13
+1
0x09
+11
0x14 to 0x1F
0
0x0A
+10
Digital Microphone Clock Frequency
Select a frequency that is within the digital microphone’s clock frequency range.
Set OSR1 = 1 when using a digital microphone.
00 = PCLK/8
01 = PCLK/6
10 = 64 x LRCLK
11 = Reserved
DIGMICL
DIGMICR
Right Digital Microphone Enable
Set PA1EN = 00 for proper operation.
0 = Disabled
1 = Enabled
1
EXTMIC
0
VALUE
Left Digital Microphone Enable
Set PA1EN = 00 for proper operation.
0 = Disabled
1 = Enabled
0x48
4
MIC1/MIC2 Preamplifier Gain
Course microphone gain adjustment.
00 = Preamplifier disabled
01 = 0dB
10 = 20dB
11 = 30dB
MIC1/MIC2 PGA
Fine microphone gain adjustment.
4
2
DESCRIPTION
External Microphone Connection
Routes INA_/EXTMIC_ to the microphone preamplifiers. Set INAEN = 0 when using
INA_/EXTMIC_ as a microphone input.
00 = Disabled
01 = MIC1 input
10 = MIC2 input
11 = Reserved
���������������������������������������������������������������� Maxim Integrated Products 66
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 3. Microphone Input Registers (continued)
REGISTER
BIT
NAME
7
INABYP
4
MIC2BYP
1
RECBYP
0x4A
DESCRIPTION
INA_/EXTMIC_ to MIC1_ Bypass Switch
0 = Disabled
1 = Enabled
MIC1_ to MIC2_ Bypass Switch
0 = Disabled
1 = Enabled
See the Output Bypass Switches section.
0
SPKBYP
Line Inputs
The device includes two sets of line inputs (Figure 7).
Each set can be configured as a stereo single-ended
input or as a mono differential input. Each input includes
adjustable gain to match a wide range of input signal
levels. If a custom gain is needed, the external gain
mode provides a trimmed feedback resistor. Set the gain
by choosing the appropriate input resistor and using the
following formula:
AVPGAIN = 20 x log (20kI/RIN)
The external gain mode also allows summing multiple
signals into a single input, by connecting multiple input
resistors as show in Figure 8, and/or inputting signals
larger than 1VP-P by adjusting the ratio of the 20kI/RIN
less than 1.
INABYP
INA1/
EXTMICP
PGAINA:
+20dB TO -6dB
INADIFF
INA2/
EXTMICN
PGAINA:
+20dB TO -6dB
LEFT
INPUT 1
LEFT
INPUT 2
PGAINB:
+20dB TO -6dB
20kI
VCM
RIGHT
INPUT 1
INB1
INBDIFF
RIGHT
INPUT 2
1VP-P(max)
INA1/EXTMICP
20kI
INA2/EXTMICN
1VP-P(max)
VCM
PGAINB:
+20dB TO -6dB
INB2
Figure 7. Line Input Block Diagram
Figure 8. Summing Multiple Input Signals into INA/INB
���������������������������������������������������������������� Maxim Integrated Products 67
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 4. Line Input Registers
REGISTER
BIT
6
0x37/0x38
NAME
DESCRIPTION
INAEXT/INBEXT
2
1
PGAINA/PGAINB
0
7
INADIFF
6
INBDIFF
0x47
Line Input A/B External Gain
Switches out the internal input resistor and selects a trimmed 20kI feedback resistor.
Use an external input resistor to set the gain of the line input.
0 = Disabled
1 = Enabled
Line Input A/B Internal Gain Settings
000 = +20dB
001 = +14dB
010 = +3dB
011 = 0dB
100 = -3dB
101 = -6dB
110 = -6dB
111 = -6dB
Line Input A Differential Enable
0 = Stereo single-ended input
1 = Mono differential input
Line Input B Differential Enable
0 = Stereo single-ended input
1 = Mono differential input
ADC Input Mixers
The IC’s stereo ADC accepts input from the microphone
amplifiers, line inputs amplifiers, and directly from the
INA1 and INA2. The ADC mixer routes any combination of the eight audio inputs to the left and right ADCs
(Figure 9).
PGAM1:
+20dB TO 0dB
PA1EN:
0/20/30dB
PGAM2:
+20dB TO 0dB
MIX
ADCL
MIXADL
PA2EN:
0/20/30dB
MIX
INADIFF
ADCR
ADREN
PGAINA:
+20dB TO -6dB
+
ADLEN
MIXADR
PGAINA:
+20dB TO -6dB
PGAINB:
+20dB TO -6dB
INBDIFF
+
PGAINB:
+20dB TO -6dB
Figure 9. ADC Input Mixer Block Diagram
���������������������������������������������������������������� Maxim Integrated Products 68
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 5. ADC Input Mixer Register
REGISTER
BIT
NAME
DESCRIPTION
7
Left/Right ADC Input Mixer
Selects which analog inputs are recorded by the left/right ADC.
1xxxxxxx = MIC1
x1xxxxxx = MIC2
xx1xxxxx = INA1 pin direct
xxx1xxxx = INA2 pin direct
xxxx1xxx = INA1
xxxxx1xx = INA2 (INADIFF = 0) or INA2 - INA1 (INADIFF = 1)
xxxxxx1x = INB1
xxxxxxx1 = INB2 (INBDIFF = 0) or INB2 - INB1 (INBDIFF = 1)
6
5
0x23/0x24
4
3
MIXADL/MIXADR
2
1
0
Record Path Signal Processing
The device’s record signal path includes both automatic
gain control (AGC) for the microphone inputs and a digital noise gate at the output of the ADC (Figure 10).
Microphone AGC
The IC’s AGC monitors the signal level at the output of the
ADC and then adjusts the MIC1 and MIC2 analog PGA
settings automatically. When the signal level is below
the predefined threshold, the gain is increased up to its
maximum (20dB). If the signal exceeds the threshold,
the gain is reduced to prevent the output signal level
exceeding the threshold. When AGC is enabled, the
microphone PGA is not user programmable. The AGC
provides a more constant signal level and improves the
available ADC dynamic range.
Noise Gate
Since the AGC increases the levels of all signals below
a user-defined threshold, the noise floor is effectively
increased by 20dB. To counteract this, the noise gate
reduces the gain at low signal levels. Unlike typical noise
gates that completely silence the output below a defined
level, the noise gate in the IC applies downward expansion. The noise gate attenuates the output at a rate of
1dB for each 2dB the signal is below the threshold with a
maximum attenuation of 12dB.
The noise gate can be used in conjunction with the AGC
or on its own. When the AGC is enabled, the noise gate
reduces the output level only when the AGC has set the
gain to the maximum setting. Figure 11 shows the gain
response resulting from using the AGC and noise gate.
AGC AND NOISE GATE
AMPLITUDE RESPONSE
0
PGAM1:
+20dB TO -6dB
AUTOMATIC
GAIN
CONTROL
PA2EN:
0/20/30dB
PGAM2:
+20dB TO 0dB
AGC ONLY
NOISE GATE
MIX
ADCL
ADLEN
MIXADL
-20
MODE1
AVFLT
AUDIO/
VOICE
FILTERS
AVLG: 0/6/
12/18dB
AVL:0dB
TO -15dB
SRMIX_
MODE
AVRG: 0/6/
12/18dB
AVR:0dB
TO -15dB
SAMPLE RATE
CONVERTER
OUTPUT AMPLITUDE (dBFS)
PA1EN:
0/20/30dB
AGC AND NOISE GATE
-40
-60
AGC AND NOISE
GATE DISABLED
-80
NOISE GATE ONLY
MIX
ADCR
ADREN
MIXADR
-100
-120
-120
-100
-80
-60
-40
-20
0
INPUT AMPLITUDE (dBFS)
Figure 10. Record Path Signal Processing Block Diagram
Figure 11. AGC and Noise Gate Input vs. Output Gain
���������������������������������������������������������������� Maxim Integrated Products 69
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 6. Record Path Signal Processing Registers
REGISTER
BIT
NAME
7
6
NG
5
AGC Gain
Reports the current AGC gain setting.
4
0x01
3
2
AGC
1
0
7
GAIN (dB)
VALUE
GAIN (dB)
0x00
+20
0x0B
+9
0x01
+19
0x0C
+8
0x02
+18
0x0D
+7
0x03
+17
0x0E
+6
0x04
+16
0x0F
+5
0x05
+15
0x10
+4
0x06
+14
0x11
+3
0x07
+13
0x12
+2
0x08
+12
0x13
+1
0x09
+11
0x14 to 0x1F
0
0x0A
+10
AGCSRC
AGCRLS
AGC Release Time
Defined as the duration from start to finish of gain increase in the region shown in Figure
12.
000 = 78ms
001 = 156ms
010 = 312ms
011 = 625ms
100 = 1.25s
101 = 2.5s
110 = 5s
111 = 10s
0x3F
4
VALUE
AGC/Noise Gate Signal Source
Determines which ADC channel the AGC and noise gates analyze. Gain is adjusted on
both channels regardless of the AGCSRC setting.
0 = Left ADC output
1 = Maximum of either the left or right ADC output
6
5
DESCRIPTION
Noise Gate Attenuation
Reports the current noise gate attenuation.
000 = 0dB
001 = 1dB
010 = 2dB
011 = 3dB to 5dB
100 = 6dB to 7dB
101 = 8dB to 9dB
110 = 10dB to 11dB
111 = 12dB
���������������������������������������������������������������� Maxim Integrated Products 70
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 6. Record Path Signal Processing Registers (continued)
REGISTER
BIT
NAME
DESCRIPTION
AGCATK
AGC Attack Time
Defined as the time required to reduce gain by 63% of the total gain reduction (one time
constant of the exponential response). Attack times are longer for low AGC threshold
levels. See Figure 12 for details.
00 = 2ms
01 = 7.2ms
10 = 31ms
11 = 123ms
3
2
0x3F
1
AGCHLD
0
Noise Gate Threshold
Gain is reduced for signals below the threshold to quiet noise. The thresholds are relative to the ADC’s full-scale output voltage.
7
6
ANTH
5
4
0x40
2
AGCTH
0
VALUE
THRESHOLD
(dBFS)
VALUE
THRESHOLD
(dBFS)
0x0
Noise gate disabled
0x8
-45
0x1
Reserved
0x9
-41
0x2
Reserved
0xA
-38
0x3
-64
0xB
-34
0x4
-62
0xC
-30
0x5
-58
0xD
-27
0x6
-53
0xE
-22
0x7
-50
0xF
-16
AGC Threshold
Gain is reduced when signals exceed the threshold to prevent clipping. The thresholds
are relative to the ADC’s full-scale voltage.
3
1
AGC Hold Time
The delay before the AGC release begins. The hold time counter starts whenever the
signal drops below the AGC threshold and is reset by any signal that exceeds the
threshold. Set AGCHLD to enable the AGC circuit. See Figure 12 for details.
00 = AGC disabled
01 = 50ms
10 = 100ms
11 = 400ms
VALUE
THRESHOLD
(dBFS)
VALUE
THRESHOLD
(dBFS)
0x0
-3
0x8
-11
0x1
-4
0x9
-12
0x2
-5
0xA
-13
0x3
-6
0xB
-14
0x4
-7
0xC
-15
0x5
-8
0xD
-16
0x6
-9
0xE
-17
0x7
-10
0xF
-18
���������������������������������������������������������������� Maxim Integrated Products 71
MAX98088
Stereo Audio Codec
with FlexSound Technology
ATTACK TIME
HOLD TIME
RELEASE TIME
Figure 12. AGC Timing
ADC Record Level Control
the digital level control to 0dB whenever possible. Digital
level control is primarily used when adjusting the record
level for digital microphones.
The IC includes separate digital level control for the left
and right ADC outputs (Figure 13). To optimize dynamic
range, use analog gain to adjust the signal level and set
NOISE GATE
AUTOMATIC
GAIN
CONTROL
ADCL
ADLEN
MODE1
AVFLT
AUDIO/
VOICE
FILTERS
AVLG: 0/6/
12/18dB
AVL:0dB
TO -15dB
SRMIX_
MODE
AVRG: 0/6/
12/18dB
AVR:0dB
TO -15dB
SAMPLE RATE
CONVERTER
ADCR
ADREN
Figure 13. ADC Record Level Control Block Diagram
���������������������������������������������������������������� Maxim Integrated Products 72
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 7. ADC Record Level Control Register
REGISTER
BIT
NAME
DESCRIPTION
Left/Right ADC Gain
00 = 0dB
01 = 6dB
10 = 12dB
11 = 18dB
5
AVLG/AVRG
4
Left/Right ADC Level
3
0x33/0x34
VALUE
GAIN (dB)
VALUE
GAIN (dB)
0x0
+3
0x8
-5
0x1
+2
0x9
-6
0x2
+1
0xA
-7
-8
2
AVL/AVR
1
0
0x3
0
0xB
0x4
-1
0xC
-9
0x5
-2
0xD
-10
0x6
-3
0xE
-11
0x7
-4
0xF
-12
speak, providing a more natural user experience. The
IC implements sidetone digitally. Doing so helps prevent
unwanted feedback into the playback signal path and
better matches the playback audio signal.
Sidetone
Enable sidetone during full-duplex operation to add a
low-level copy of the recorded audio signal to the playback audio signal (Figure 14). Sidetone is commonly
used in telephony to allow the speaker to hear himself
DV1G:
0/6/12/18dB
DVST:
0dB TO -60dB
SIDETONE
+
MIX
DSTS
MULTI BAND ALC
DVEQ1:
0dB TO -15dB
AUTOMATIC
GAIN
CONTROL
NOISE GATE
MODE1
AVFLT
ADLEN
ADCL
ADCR
ADREN
5-BAND
PARAMETRIC
EQ
EQ1EN
AUDIO/
VOICE
FILTERS
AVLG: 0/6/
12/18dB
AVL:0dB
TO -15dB
SRMIX_
MODE
5-BAND
PARAMETRIC
EQ
DVEQ2:
0dB TO -15dB
EQ2EN
EXCURSION LIMITER
AVRG: 0/6/
12/18dB
AVR:0dB
TO -15dB
DV2:
0dB TO -15dB
MIX
AUDIO/
FILTERS
MIXDAL
DACL
DALEN
DCB2
SAMPLE RATE
CONVERTER
DV1:
0dB TO -15dB
AUDIO/
VOICE
FILTERS
MODE1
DVFLT
MIX
MIXDAR
DACR
DAREN
Figure 14. Sidetone Block Diagram
���������������������������������������������������������������� Maxim Integrated Products 73
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 8. Sidetone Register
REGISTER
BIT
NAME
7
DSTS
6
Sidetone Level
Adjusts the sidetone signal level. All levels are referenced to the ADC’s full-scale output.
4
3
0x2E
2
1
0
DESCRIPTION
Sidetone Source
Selects which ADC output is fed back as sidetone. When mixing the left and right ADC
outputs, each is attenuated by 6dB to prevent full-scale signals from clipping.
00 = Sidetone disabled
01 = Left ADC
10 = Right ADC
11 = Left + Right ADC
DVST
VALUE
LEVEL (dB)
VALUE
LEVEL (dB)
0x00
Sidetone disabled
0x10
-30.5
0x01
-0.5
0x11
-32.5
0x02
-2.5
0x12
-34.5
0x03
-4.5
0x13
-36.5
0x04
-6.5
0x14
-38.5
0x05
-8.5
0x15
-40.5
0x06
-10.5
0x16
-42.5
0x07
-12.5
0x17
-44.5
0x08
-14.5
0x18
-46.5
0x09
-16.5
0x19
-48.5
0x0A
-18.5
0x1A
-50.5
0x0B
-20.5
0x1B
-52.5
0x0C
-22.5
0x1C
-54.5
0x0D
-24.5
0x1D
-56.6
0x0E
-26.5
0x1E
-58.5
0x0F
-28.5
0x1F
-60.5
Digital Audio Interfaces
The IC includes two separate playback signal paths and
one record signal path. Digital audio interface 1 (DAI1)
is used to transmit the recorded stereo audio signal and
receive a stereo audio signal for playback. Digital audio
interface 2 (DAI2) is used to receive a second stereo
audio signal. Use DAI1 for all full-duplex operations and
for all voice signals. Use DAI2 for music and to mix two
playback audio signals. The digital audio interfaces are
separate from the audio ports to enable either interface
to communicate with any external device connected to
either audio port.
Each audio interface can be configured in a variety of formats including left justified, I2S, PCM, and time division
multiplexed (TDM). TDM mode supports up to 4 mono
audio slots in each frame. The IC can use up to 2 mono
slots per interface, leaving the remaining two slots available for another device. Table 9 shows how to configure
the device for common digital audio formats. Figures 16
and 17 show examples of common audio formats. By
default, SDOUTS1 and SDOUTS2 are set high impedance when the IC is not outputting data to facilitate sharing the bus. Configure the interface in TDM mode using
only slot 1 to transmit and receive mono PCM voice data.
The IC’s digital audio interfaces support both ADC to DAC
loop-through and digital loopback. Loop-through allows
the signal converted by the ADC to be routed to the DAC
for playback. The signal is routed from the record path to
the playback path in the digital audio interface to allow
the IC’s full complement of digital signal processing to
be used. Loopback allows digital data input to either
SDINS1 or SDINS2 to be routed from one interface to the
���������������������������������������������������������������� Maxim Integrated Products 74
MAX98088
Stereo Audio Codec
with FlexSound Technology
other for output on SDOUTS2 or SDOUTS1. Both interfaces must be configured for the same sample rate, but
the interface format need not be the same. This allows
LRCLKS1
SDOUTS1
SDINS1
DVDDS1
BCLKS2
SDOUTS2
SDINS2
DVDDS2
DAI1
SDIN2
SDOUT2
BCLK2
SDIN1
SDOUT1
LRCLK1
SEL2
BCLK1
SEL1
LRCLKS2
LRCLK2
BCLKS1
the IC to route audio data from one device to another,
converting the data format as needed. Figure 15 shows
the available digital signal routing options.
DAI2
MAS1
MAS1
BIT
CLOCK
FRAME
CLOCK
HIZOFF1
SDOEN1
DATA
OUTPUT
SDIEN1
MAS2
DATA
INPUT
HIZOFF2
SDOEN2
MAS2
BIT
CLOCK
FRAME
CLOCK
DATA
OUTPUT
SDIEN2
DATA
INPUT
LBEN1
LBEN2
MUX
+
LTEN1
DAI1
RECORD PATH
DAI1
PLAYBACK PATH
DAI2
PLAYBACK PATH
Figure 15. Digital Audio Signal Routing
Table 9. Common Digital Audio Formats
MODE
WCI1/WCI2
BCI1/BCI2
DLY1/DLY2
TDM1/TDM2
Left Justified
1
0
0
0
SLOTL1/SLOTL2 SLOTR1/SLOTR2
X
X
I2S
0
0
1
0
X
X
PCM
X
1
X
1
0
0
TDM
X
1
X
1
Set as desired
���������������������������������������������������������������� Maxim Integrated Products 75
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 10. Digital Audio Interface Registers
REGISTER
BIT
7
6
5
NAME
MAS1/MAS2
DAI1/DAI2 Master Mode
In master mode, DAI1/DAI2 outputs LRCLK and BCLK. In slave mode, DAI1/DAI2
accept LRCLK and BCLK as inputs.
0 = Slave mode
1 = Master mode
WCI1/WCI2
DAI1/DAI2 Word Clock Invert
TDM1/TDM2 = 0:
0 = Left-channel data is transmitted while LRCLK is low.
1 = Right-channel data is transmitted while LRCLK is low.
TDM1/TDM2 = 1:
Always set WCI = 0.
BCI1/BCI2
DAI1/DAI2 Bit Clock Invert
BCI1/BCI2 must be set to 1 when TDM1/TDM2 = 1.
0 = SDIN is accepted on the rising edge of BCLK.
SDOUT is valid on the rising edge of BCLK.
1 = SDIN is accepted on the falling edge of BCLK.
SDOUT is valid on the falling edge of BCLK.
Master Mode:
0 = LRCLK transitions on the falling edge of BCLK.
1 = LRCLK transitions on the rising edge of BCLK.
DLY1/DLY2
DAI1/DAI2 Data Delay
DLY1/DLY2 has no effect when TDM1/TDM2 = 1.
0 = The most significant data bit is clocked on the first active BCLK edge after an
LRCLK transition.
1 = The most significant data bit is clocked on the second active BCLK edge after an
LRCLK transition.
TDM1/TDM2
DAI1/DAI2 Time-Division Multiplex Mode (TDM Mode)
Set TDM1/TDM2 when communicating with devices that use a frame synchronization
pulse on LRCLK instead of a square wave.
0 = Disabled
1 = Enabled (BCI1/BCI2 must be set to 1)
FSW1/FSW2
DAI1/DAI2 Wide Frame Sync Pulse
Increases the width of the frame sync pulse to the full data width when TDM1/TDM2 =
1. FSW1/FSW2 has no effect when TDM1/TDM2 = 0.
0 = Disabled
1 = Enabled
0x14/0x1C
4
2
1
0
DESCRIPTION
WS1/WS2
DAI1/DAI2 Audio Data Bit Depth
Determines the maximum bit depth of audio being transmitted and received. Data is
always 16 bit when TDM1/TMD2 = 0.
0 = 16 bits
1 = 24 bits
���������������������������������������������������������������� Maxim Integrated Products 76
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 10. Digital Audio Interface Registers (continued)
REGISTER
BIT
NAME
7
OSR1
6
5
DAC_OSR1/
DAC_OSR2
DAC Oversample Clock. Select PCLK/2 for higher performance. Select PCLK/4 for
lower consumption.
1 = DAC input clock = PCLK/2
0 = DAC input clock = PCLK/4
BSEL1/
BSEL2
DAI1/DAI2 BCLK Output Frequency
When operating in master mode, BSEL1/BSEL2 set the frequency of BCLK. When
operating in slave mode, BSEL1/BSEL2 have no effect. Select the lowest BCLK frequency that clocks all data input to the DAC and output by the ADC.
000 = BCLK disabled
001 = 64 x LRCLK
010 = 48 x LRCLK
011 = 128 x LRCLK (invalid for DHF1/DHF2 = 1)
100 = PCLK/2
101 = PCLK/4
110 = PCLK/8
111 = PCLK/16
0x15/0x1D
2
1
0
7
SEL1/SEL2
6
5
3
DAI1/DAI2 Audio Port Selector
Selects which port is used by DAI1/DAI2.
00 = None
01 = Port S1
10 = Port S2
11 = Reserved
LTEN1
DAI1 Digital Loopthrough
Connects the output of the record signal path to the input of the playback path. Data
input to DAI1 from an external device is mixed with the recorded audio signal.
0 = Disabled
1 = Enabled
LBEN1/
LBEN2
DAI1/DAI2 Digital Audio Interface Loopback
LBEN1 routes the digital audio input to DAI1 back out on DAI2. LBEN2 routes the digital audio input to DAI2 back out on DAI1. Selecting LBEN2 disables the ADC output
data.
0 = Disabled
1 = Enabled
DMONO1/
DMONO2
DAI1/DAI2 DAC Mono Mix
Mixes the left and right digital input to mono and routes the combined signal to the left
and right playback paths. The left and right input data is attenuated by 6dB prior to the
mono mix.
0 = Disabled
1 = Enabled
0x16/0x1E
4
DESCRIPTION
ADC Oversampling Ratio
Use the higher setting for maximum performance. Use the lower setting for reduced
power consumption at the expense of performance.
00 = 96x
01 = 64x
10 = Reserved
11 = Reserved
���������������������������������������������������������������� Maxim Integrated Products 77
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 10. Digital Audio Interface Registers (continued)
REGISTER
BIT
NAME
DESCRIPTION
2
HIZOFF1/
HIZOFF2
Disable DA1/DAI2 Output High-Impedance Mode
Normally SDOUT is set high impedance between data words. Set HIZOFF1/HIZOFF2 to
force a level on SDOUT at all times.
0 = Disabled
1 = Enabled
1
SDOEN1/
SDOEN2
DAI1/DAI2 Record Path Output Enable
DAI2 outputs data only if LBEN1 = 1.
0 = Disabled
1 = Enabled
0
SDIEN1/
SDIEN2
DAI1/DAI2 Playback Path Input Enable
0 = Disabled
1 = Enabled
0x16/0x1E
7
SLOTL1/
SLOTL2
6
5
SLOTR1/
SLOTR2
0x17/0x1F
4
3
2
1
0
SLOTDLY1/
SLOTDLY2
TDM Left Time Slot
Selects which of the four slots is used for left data on DAI1/DAI2. If the same slot is
selected for left and right audio, left audio is placed in the slot.
00 = Slot 1
01 = Slot 2
10 = Slot 3
11 = Slot 4
TDM Right Time Slot
Selects which of the four slots is used for right data on DAI1/DAI2. If the same slot is
selected for left and right audio, left audio is placed in the slot.
00 = Slot 1
01 = Slot 2
10 = Slot 3
11 = Slot 4
TDM Slot Delay
Adds 1 BCLK cycle delay to the data in the specified TDM slot.
1xxx = Slot 4 delayed
x1xx = Slot 3 delayed
xx1x = Slot 2 delayed
xxx1 = Slot 1 delayed
���������������������������������������������������������������� Maxim Integrated Products 78
MAX98088
Stereo Audio Codec
with FlexSound Technology
WCI_ = 0, BCI_ = 0, DLY_ = 0, TDM_ = 0, FSW_ = 0, WS_ = 0, HIZOFF_ = 1, SLOTL_ = 0, SLOTR_ = 0
LRCLK
SDOUT
RIGHT
LEFT
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
BCLK
SDIN
WCI_ = 1, BCI_ = 0, DLY_ = 0, TDM_ = 0, FSW_ = 0, WS_ = 0, HIZOFF_ = 1, SLOTL_ = 0, SLOTR_ = 0
LRCLK
SDOUT
LEFT
RIGHT
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
BCLK
SDIN
WCI_ = 0, BCI_ = 1, DLY_ = 0, TDM_ = 0, FSW_ = 0, WS_ = 0, HIZOFF_ = 1, SLOTL_ = 0, SLOTR_ = 0
LRCLK
SDOUT
RIGHT
LEFT
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
BCLK
SDIN
WCI_ = 0, BCI_ = 0, DLY_ = 1, TDM_ = 0, FSW_ = 0, WS_ = 0, HIZOFF_ = 1, SLOTL_ = 0, SLOTR_ = 0
LRCLK
SDOUT
LEFT
RIGHT
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
BCLK
SDIN
Figure 16. Non-TDM Data Format Examples
���������������������������������������������������������������� Maxim Integrated Products 79
MAX98088
Stereo Audio Codec
with FlexSound Technology
WCI_ = 0, BCI_ = 1, DLY_ = 0, TDM_ = 1, FSW_ = 0, WS_ = 0, HIZOFF_ = 0, SLOTL_ = 0, SLOTR_ = 1
LRCLK
SDOUT
HI-Z
L15 L14 L13 L12 L11 L10 L9
L8
L7
L15 L14 L13 L12 L11 L10 L9
L8 L7
L6
L5
L4
L3
L2
L1
L0 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0
L4 L3
L2
L1 L0 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0
HI-Z
BCLK
SDIN
L6 L5
WCI_ = 0, BCI_ = 1, DLY_ = 0, TDM_ = 1, FSW_ = 1, WS_ = 0, HIZOFF_ = 0, SLOTL_ = 0, SLOTR_ = 1
LRCLK
SDOUT
HI-Z
L15 L14 L13 L12 L11 L10 L9
L8
L7
L15 L14 L13 L12 L11 L10 L9
L8 L7
L6
L5
L4
L3
L2
L1
L0 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0
L4 L3
L2
L1 L0 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0
HI-Z
BCLK
SDIN
L6 L5
WCI_ = 0, BCI_ = 1, DLY_ = 0, TDM_ = 1, FSW_ = 0, WS_ = 0, HIZOFF_ = 1, SLOTL_ = 0, SLOTR_ = 1
LRCLK
SDOUT
L15 L14 L13 L12 L11 L10 L9
L8 L7
L6 L5
L4 L3
L2
L1 L0 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0
L15 L14 L13 L12 L11 L10 L9
L8 L7
L6 L5
L4 L3
L2
L1 L0 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0
BCLK
SDIN
WCI_ = 0, BCI_ = 1, DLY_ = 0, TDM_ = 1, FSW_ = 0, WS_ = 0, HIZOFF_ = 0, SLOTL_ = 2, SLOTR_ = 3
LRCLK
HI-Z
SDOUT
32 CYCLES
L15 L14 L13 L12 L11 L10 L9
L8
L7
L15 L14 L13 L12 L11 L10 L9
L8 L7
L6
L5
L4
L3
L2
L1
L0 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0
L4 L3
L2
L1 L0 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0
HI-Z
BCLK
SDIN
L6 L5
WCI_ = 0, BCI_ = 1, DLY_ = 0, TDM_ = 1, FSW_ = 0, WS_ = 0, HIZOFF_ = 0, SLOTL_ = 0, SLOTR_ = 1
LRCLK
16 CYCLES
SDOUT
16 CYCLES
16 CYCLES
HI-Z
L
L
L
L
L
L
L
L
R
R
R
R
R
R
R
R
HI-Z
L
L
L
L
L
L
L
L
R
R
R
R
R
R
R
R
16 CYCLES
HI-Z
BCLK
SDIN
Figure 17. TDM Mode Data Format Examples
���������������������������������������������������������������� Maxim Integrated Products 80
MAX98088
Stereo Audio Codec
with FlexSound Technology
Clock Control
The digital signal paths in the IC require a master clock
(MCLK) between 10MHz and 60MHz to function. The
MAX98088 requires an internal clock between 10MHz
and 20MHz. A prescaler divides MCLK by 1, 2, or 4 to
create the internal clock (PCLK). PCLK is used to clock
all portions of the IC.
The MAX98088 includes two digital audio signal paths,
both capable of supporting any sample rate from 8kHz
to 96kHz. Each path is independently configured to allow
different sample rates. To accommodate a wide range
of system architectures, four main clocking modes are
supported:
U PLL Mode: When operating in slave mode, enable the
PLL to lock onto any LRCLK input. This mode requires
the least configuration, but provides the lowest performance. Use this mode to simplify initial setup or
when normal mode and exact integer mode cannot
be used.
U Normal Mode: This mode uses a 15-bit clock divider
to set the sample rate relative to PCLK. This allows
high flexibility in both the PCLK and LRCLK frequencies and can be used in either master or slave mode.
U Exact Integer Mode (DAI1 only): In both master and
slave modes, common MCLK frequencies (12MHz,
13MHz, 16MHz, and 19.2MHz) can be programmed
to operate in exact integer mode for both 8kHz and
16kHz sample rates. In these modes, the MCLK and
LRCLK rates are selected by using the FREQ1 bits
instead of the NI, and PLL control bits.
U DAC Low-Power Mode: This mode bypasses the
PLL for reduce power consumptions and uses fixed
counters to generate the clocks. The DAI__DAC_LP
bits override the other clock settings.
Table 11. Clock Control Registers
REGISTER
BIT
NAME
5
0x10
PSCLK
4
6
SR1/SR2
5
4
MCLK Prescaler
Generates PCLK, which is used by all
00 = PCLK disabled
01 = 10MHz P MCLK P 20MHz (PCLK
10 = 20MHz P MCLK P 40MHz (PCLK
11 = 40MHz P MCLK P 60MHz (PCLK
internal circuitry.
= MCLK)
= MCLK/2)
= MCLK/4)
DAI1/DAI2 Sample Rate
Used by the ALC to correctly set the dual-band crossover frequency and the excursion
limiter to set the predefined corner frequencies.
7
0x11/0x19
DESCRIPTION
VALUE
SAMPLE RATE
(kHz)
VALUE
SAMPLE RATE
(kHz)
0x0
Reserved
0x8
48
88.2
0x1
8
0x9
0x2
11.025
0xA
96
0x3
16
0xB
Reserved
0x4
22.05
0xC
Reserved
0x5
24
0xD
Reserved
0x6
32
0xE
Reserved
0x7
44.1
0xF
Reserved
���������������������������������������������������������������� Maxim Integrated Products 81
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 11. Clock Control Registers (continued)
REGISTER
BIT
NAME
DESCRIPTION
Exact Integer Mode
Overrides PLL1 and NI1 and configures a specific PCLK to LRCLK ratio.
3
0x11
2
FREQ1
1
7
0x12/0x1A
PLL1/PLL2
6
4
3
2
1
7
SAMPLE RATE
VALUE
0x0
Disabled
0x8
0x1
Reserved
0x9
0x2
Reserved
0xA
0x3
Reserved
0xB
0x4
Reserved
0xC
0x5
Reserved
0xD
0x6
Reserved
0xE
0x7
Reserved
0xF
SAMPLE RATE
PCLK = 12MHz,
LRCLK = 8kHz
PCLK = 12MHz,
LRCLK = 16kHz
PCLK = 13MHz,
LRCLK = 8kHz
PCLK = 13MHz,
LRCLK = 16kHz
PCLK = 16MHz,
LRCLK = 8kHz
PCLK = 16MHz,
LRCLK = 16kHz
PCLK = 19.2MHz,
LRCLK = 8kHz
PCLK = 19.2MHz,
LRCLK = 16kHz
PLL Mode Enable (Slave Mode Only)
PLL1/PLL2 enables a digital PLL that locks on to the externally supplied LRCLK
frequency and automatically sets the LRCLK divider (NI1/NI2).
0= Disabled
1= Enabled
Normal Mode LRCLK Divider
When PLL1/PLL2 = 0, the frequency of LRCLK is determined by NI1/NI2. See Table 12
for common NI values.
5
0
VALUE
NI1/
NI2
6
5
SAMPLE RATE
DHF1/DHF2
8kHz P LRCLK P 48kHz
0
48kHz < LRCLK P 96kHz
1
NI1/NI2 FORMULA
4
3
0x13/0x1B
fLRCLK = LRCLK frequency
fPCLK = Prescaled MCLK frequency (PCLK)
2
1
0
NI1[0]/NI2[0]
Rapid Lock Mode
Program NI1/NI2 to the nearest valid ratio and set NI1[0]/NI2[0] when PLL1/PLL2 = 1
to enable rapid lock mode. Normally, the PLL automatically calculates and dynamically
adjusts NI1/NI2. When rapid lock mode is properly configured, the PLL starting point is
much closer to the correct value, thus speeding up lock time. Wait one LRCLK period
after programming NI1/NI2 before setting PLL1/PLL2 = 1.
���������������������������������������������������������������� Maxim Integrated Products 82
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 11. Clock Control Registers (continued)
REGISTER
BIT
NAME
DESCRIPTION
DAI_ DAC Low Power Select.
These bits setup the clocks to be generated from fixed counters that bypass the PLL
for DAC low power mode.
7
VALUE
SETTING
FILTER
SELECT
VALUE
SETTING
FILTER
SELECT
0x0
PLL derived
clock
—
0x8
PCLK =
2304 x
LRCLK
Voice
5
0x1
PCLK = 128
x LRCLK
Audio
96kHz
0x9
Reserved
—
4
0x2
PCLK = 192
x LRCLK
Audio
96kHz
0xA
Reserved
—
0x3
PCLK = 256
x LRCLK
Audio
48kHz
0xB
Reserved
—
0x4
PCLK = 384
x LRCLK
Audio
48kHz
0xC
Reserved
—
0x5
PCLK = 768
x LRCLK
Voice
0xD
Reserved
—
1
0x6
PCLK =
1152 x
LRCLK
Voice
0xE
Reserved
—
0
0x7
PCLK =
1536 x
LRCLK
Voice
0xF
Reserved
—
6
DAI2_DAC_LP
0x4F
3
2
DAI1_DAC_LP
3
2
DAC2DITHEN
DAI2 DAC Input Dither Enable
DAC2DITHEN is recommended to be set when DAI2_DAC_LP = 0000.
0 = Disabled
1 = Enabled
DAC1DITHEN
DAI1 DAC Input Dither 1 Enable
DAC1DITHEN is recommended to be set when DAI1_DAC_LP = 0000.
0 = Disabled
1 = Enabled
CGM2_EN
DAI2 Clock Gen Module Enable
CGM1_EN has to be set along with CGM2_EN to enable the clock generation for the
DAI2 DAC playback path.
0 = Disabled
1 = Enabled
CGM1_EN
DAI1/Device Clock Gen Module Enable
CGM1_EN enables the device clock generation, and needs to be set for DAC playback
or ADC record.
0 = Disabled
1 = Enabled
0x50
1
0
���������������������������������������������������������������� Maxim Integrated Products 83
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 12. Common NI1/NI2 Values
LRCLK (kHz)
PCLK (MHz)
DHF1/2 = 0
8
11.025
12
10
13A9
1B18
11
11E0
18A2
11.2896
116A
1800
1A1F
12
1062
1694
1893
12.288
1000
160D
13
0F20
14D8
DHF1/2 = 1
16
22.05
24
32
44.1
48
64
88.2
1D7E
2752
3631
3AFB
4EA5
1ACF
23BF
3144
359F
477E
22D4
3000
343F
20C5
2D29
3127
1800
2000
2C1A
16AF
1E3F
29AF
96
6C61
75F7
4EA5
6C61
75F7
6287
6B3E
477E
6287
6B3E
45A9
6000
687D
45A9
6000
687D
4189
5A51
624E
4189
5A51
624E
3000
4000
5833
6000
4000
5833
6000
2D5F
3C7F
535F
5ABE
3C7F
535F
5ABE
16
0C4A
10EF
126F
1893
21DE
24DD
3127
43BD
49BA
3127
43BD
49BA
16.9344
0B9C
1000
116A
1738
2000
22D4
2E71
4000
45A9
2E71
4000
45A9
18.432
0AAB
0EB3
1000
1555
1D66
2000
2AAB
3ACD
4000
2AAB
3ACD
4000
20
09D5
0D8C
0EBF
13A9
1B18
1D7E
2752
3631
3AFB
2752
3631
3AFB
Note: Values in bold are exact integers that provide maximum full-scale performance.
interfaces (SDIN1/SDIN2), and for the resulting mixed
audio to output on either audio interface through SDOUT1
or SDOUT2.
Sample Rate Converter
The sample rate conversion scheme enables the mixing of asynchronous audio data from the digital audio
DV1G:
0/6/12/18dB
DVST:
0dB TO -60dB
SIDETONE
+
MIX
DSTS
MULTI BAND ALC
DVEQ1:
0dB TO -15dB
AUTOMATIC
GAIN
CONTROL
NOISE GATE
MODE1
AVFLT
ADLEN
ADCL
ADCR
ADREN
5-BAND
PARAMETRIC
EQ
EQ1EN
AUDIO/
VOICE
FILTERS
AVLG: 0/6/
12/18dB
AVL:0dB
TO -15dB
SRMIX_
MODE
5-BAND
PARAMETRIC
EQ
DVEQ2:
0dB TO -15dB
EQ2EN
EXCURSION LIMITER
AVRG: 0/6/
12/18dB
AVR:0dB
TO -15dB
DV2:
0dB TO -15dB
MIX
AUDIO/
FILTERS
MIXDAL
DACL
DALEN
DCB2
SAMPLE RATE
CONVERTER
DV1:
0dB TO -15dB
AUDIO/
VOICE
FILTERS
MODE1
DVFLT
MIX
MIXDAR
DACR
DAREN
Figure 18. Sample Rate Converter
���������������������������������������������������������������� Maxim Integrated Products 84
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 13. Sample Rate Converter
REGISTER
0x21
BIT
NAME
DESCRIPTION
4
SRMIX_MODE
3
SRMIX_ENL
2
SRMIX_ENR
1
SRC_ENL
0
SRC_ENR
Sample Rate Mix Mode. Sets mixing configuration applied to the sample rate converted channel(s).
0 = (DAI1 + DAI2)
1 = (DAI1 + DAI2)/2
Sample Rate Mix Enable. If enabled, mixes data on DAI1 and DAI2. If cleared, SCR
data source is DAI2 only.
0 = SRC mix disable
1 = SRC mix enable
Sample Rate Converter Enable. Select if the SRC is enabled on per channel basis.
0 = Sample rate converter disable
1 = Sample rate converter enable
Use music mode when processing high-fidelity audio
content. The music FIR filters reduce power consumption and are linear phase to maintain stereo imaging.
An optional DC-blocking filter is available to eliminate
unwanted DC offset.
Passband Filtering
Each digital signal path in the IC includes options for
defining the path bandwidth (Figure 19). The playback
and record paths connected to DAI1 support both voice
and music filtering while the playback path connected to
DAI2 supports music filtering only.
In music mode, a second set of FIR filters are available to
support sample rates greater than 50kHz. The filters can
be independently selected for DAI1 and DAI2 and support both the playback and record audio paths.
The voice IIR filters provide greater than 70dB stopband
attenuation at frequencies above fS/2 to reduce aliasing.
Three selectable highpass filters eliminate unwanted lowfrequency signals.
DV1G:
0/6/12/18dB
DVST:
0dB TO -60dB
SIDETONE
+
MIX
DSTS
MULTI BAND ALC
DVEQ1:
0dB TO -15dB
AUTOMATIC
GAIN
CONTROL
NOISE GATE
MODE1
AVFLT
ADLEN
ADCL
5-BAND
PARAMETRIC
EQ
EQ1EN
AUDIO/
VOICE
FILTERS
AVLG: 0/6/
12/18dB
AVL:0dB
TO -15dB
SRMIX_
MODE
5-BAND
PARAMETRIC
EQ
DVEQ2:
0dB TO -15dB
EQ2EN
EXCURSION LIMITER
AVRG: 0/6/
12/18dB
AVR:0dB
TO -15dB
DV2:
0dB TO -15dB
MIX
AUDIO/
FILTERS
MIXDAL
DACL
DALEN
DCB2
SAMPLE RATE
CONVERTER
ADCR
ADREN
DV1:
0dB TO -15dB
AUDIO/
VOICE
FILTERS
MODE1
DVFLT
MIX
MIXDAR
DACR
DAREN
Figure 19. Digital Passband Filtering Block Diagram
���������������������������������������������������������������� Maxim Integrated Products 85
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 14. Passband Filtering Registers
REGISTER
BIT
NAME
7
MODE1
6
AVFLT1
4
0x18
DHF1
2
DVFLT1
0
AVFLT1
0
See Table 15
1
Select a nonzero value to enable
the DC-blocking filter.
DAI1 High Sample Rate Mode
Selects the sample rate range.
0 = 8kHz P LRCLK P 48kHz
1 = 48kHz P LRCLK P 96kHz
MODE1
DVFLT1
0
See Table 15
1
Select a nonzero value to enable
the DC-blocking filter.
DHF2
DAI2 High Sample Rate Mode
Selects the sample rate range.
0 = 8kHz P LRCLK P 48kHz
1 = 48kHz < LRCLK P 96kHz
DCB2
DAI2 DC Blocking Filter
Enables a DC-blocking filter on the DAI2 playback audio path.
0 = Disabled
1 = Enabled
0x20
0
MODE1
DAI1 DAC Highpass Filter Mode
1
3
DAI1 Passband Filtering Mode
0 = Voice filters
1 = Music filters (recommended for fS > 24kHz)
DAI1 ADC Highpass Filter Mode
5
3
DESCRIPTION
���������������������������������������������������������������� Maxim Integrated Products 86
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 15. Voice Highpass Filters
AVFTL/DVFLT VALUE
INTENDED SAMPLE RATE
FILTER RESPONSE
000
N/A
Disabled
0
001/011
16kHz/8kHz
AMPLITUDE (dB)
-10
-20
-30
-40
-50
-60
0
200
400
600
800
1000
800
1000
FREQUENCY (Hz)
0
010/100
16kHz/8kHz
AMPLITUDE (dB)
-10
-20
-30
-40
-50
-60
0
200
400
600
FREQUENCY (Hz)
0
101
8kHz to 48kHz
AMPLITUDE (dB)
-10
-20
-30
-40
-50
LRCLK = 48kHz
-60
0
200
400
600
800
1000
FREQUENCY (Hz)
110/111
N/A
Reserved
���������������������������������������������������������������� Maxim Integrated Products 87
MAX98088
Stereo Audio Codec
with FlexSound Technology
Playback Path Signal Processing
The IC playback signal path includes automatic level
control (ALC) and a 5-band parametric equalizer (EQ)
(Figure 20). The DAI1 and DAI2 playback paths include
separate ALCs controlled by a single set of registers.
Two completely separate parametric EQs are included
for the DAI1 and DAI2 playback paths.
Automatic Level Control
The automatic level control (ALC) circuit ensures maximum signal amplitude without producing audible clipping. This is accomplished by a variable gain stage that
works on a sample by sample basis to increase the gain
up to 12dB. A look-ahead circuit determines if the next
sample exceeds full scale and reduces the gain so that
the sample is exactly full scale.
A programmable low signal threshold determines the
minimum signal amplitude that is amplified. Select a
threshold that prevents the amplification of background
noise. When the signal level drops below the low signal
threshold, the ALC reduces the gain to 0dB until the signal increases above the threshold. Figure 21 shows an
example of ALC input vs. output curves.
The ALC can optionally be configured in dual-band
mode. In this mode, the input signal is filtered into two
bands with a 5kHz center frequency. Each band is
routed through independent ALCs and then summed
together. In multiband mode, both bands use the same
parameters.
OUTPUT SIGNAL
(dBFS)
0
LOW-LEVEL
-12
0
THRESHOLD
ALC WITH ALCTH ≠ 000
INPUT
SIGNAL
(dBFS)
OUTPUT SIGNAL
(dBFS)
0
DV1G:
0/6/12/18dB
+
0
INPUT
SIGNAL
(dBFS)
0
INPUT
SIGNAL
(dBFS)
MULTI BAND ALC
DVEQ1:
0dB TO -15dB
5-BAND
PARAMETRIC
EQ
LOW-LEVEL
THRESHOLD
DVEQ2:
0dB TO -15dB
ALC WITH ALCTH = 000
5-BAND
PARAMETRIC
EQ
EQ1EN
-12
OUTPUT SIGNAL
(dBFS)
EQ2EN
EXCURSION LIMITER
DV2:
0dB TO -15dB
DV1:
0dB TO -15dB
MIX
AUDIO/
FILTERS
MIXDAL
DACL
0
DALEN
DCB2
AUDIO/
VOICE
FILTERS
MODE1
DVFLT
MIX
MIXDAR
DACR
DAREN
Figure 20. Playback Path Signal Processing Block Diagram
LOW-LEVEL
THRESHOLD
-12
ALC DISABLED
Figure 21. ALC Input vs. Output Examples
���������������������������������������������������������������� Maxim Integrated Products 88
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 16. Automatic Level Control Registers
BIT
7
NAME
ALCEN
0x43
ALCRLS
4
3
0
VALUE
000
001
010
011
100
101
110
111
ALC RELEASE TIME (s)
8
4
2
1
0.5
0.25
Reserved
Reserved
ALCMB
Multiband Enable
Enables dual-band processing with a 5kHz center frequency. SR1 and SR2 must be
configured properly to achieve the correct center frequency for each playback path.
0 = Single-band ALC
1 = Dual-band ALC
ALCTH
Low Signal Threshold
Selects the minimum signal level to be boosted by the ALC.
000 = -JdB (low-signal threshold disabled)
001 = -12dB
010 = -18dB
011 = -24dB
100 = -30dB
101 = -36dB
110 = -42dB
111 = -48dB
2
1
ALC Enable
Enables ALC on both the DAI1 and DAI2 playback paths.
0 = Disabled
1 = Enabled
ALC and Excursion Limiter Release Time
Sets the release time for both the ALC and Excursion Limiter. See the Excursion
Limiter section for Excursion Limiter release times. ALC release time is defined as the
time required to adjust the gain from 12dB to 0dB.
6
5
DESCRIPTION
Parametric Equalizer
The parametric EQ contains five independent biquad
filters with programmable gain, center frequency, and
bandwidth. Each biquad filter has a gain range of Q12dB
and a center frequency range from 20Hz to 20kHz. Use a
filter Q less than that shown in Figure 22 to achieve ideal
frequency responses. Setting a higher Q results in nonideal frequency response. The biquad filters are series
connected, allowing a total gain of Q60dB.
1000
MAXIMUM RECOMMENDED FILTER Q
REGISTER
fs = 8kHz
100
fs = 48kHz
10
fs = 96kHz
1
0.1
100
1000
10,000
100,000
CENTER FREQUENCY (Hz)
Figure 22. Maximum Recommended Filter Q vs. Frequency
���������������������������������������������������������������� Maxim Integrated Products 89
MAX98088
Stereo Audio Codec
with FlexSound Technology
Use the attenuator at the EQ’s input to avoid clipping
the signal. The attenuator can be programmed for fixed
attenuation or dynamic attenuation based on signal level.
If the dynamic EQ clip detection is enabled, the signal
level from the EQ is fed back to the attenuator circuit to
determine the amount of gain reduction necessary to
avoid clipping.
The MAX98088 EV kit software includes a graphical interface for generating the EQ coefficients. The coefficients
are sample rate dependent and stored in registers 0x52
through 0xB5.
Table 17. EQ Registers
REGISTER
BIT
NAME
4
EQCLP1/
EQCLP2
2
DVEQ1/DVEQ2
1
0
7
0x49
DAI1/DAI2 EQ Clip Detection
Automatically controls the EQ attenuator to prevent clipping in the EQ.
0 = Enabled
1 = Disabled
DAI1/DAI2 EQ Attenuator
Provides attenuation to prevent clipping in the EQ when full-scale signals are boosted. DVEQ1/DVEQ2 operates only when EQ1EN/EQ2EN = 1 and EQCLP1/EQCLP2
= 1.
3
0x30/0x32
DESCRIPTION
VALUE
GAIN (dB)
VALUE
GAIN (dB)
0x0
0
0x8
-8
0x1
-1
0x9
-9
0x2
-2
0xA
-10
0x3
-3
0xB
-11
0x4
-4
0xC
-12
0x5
-5
0xD
-13
0x6
-6
0xE
-14
0x7
-7
0xF
-15
VS2EN
See the Click-and-Pop Reduction section.
6
VSEN
5
ZDEN
1
EQ2EN
DAI2 EQ Enable
0 = Disabled
1 = Enabled
0
EQ1EN
DAI1 EQ Enable
0 = Disabled
1 = Enabled
���������������������������������������������������������������� Maxim Integrated Products 90
MAX98088
Stereo Audio Codec
with FlexSound Technology
Playback Level Control
allows boost when MODE1 = 0 and attenuation in any
mode. The DAI2 signal path allows attenuation only.
The IC includes separate digital level control for the DAI1
and DAI2 playback audio paths. The DAI1 signal path
DV1G:
0/6/12/18dB
+
MULTI BAND ALC
DVEQ1:
0dB TO -15dB
5-BAND
PARAMETRIC
EQ
DVEQ2:
0dB TO -15dB
5-BAND
PARAMETRIC
EQ
EQ1EN
EQ2EN
EXCURSION LIMITER
DV2:
0dB TO -15dB
DV1:
0dB TO -15dB
MIX
AUDIO/
FILTERS
MIXDAL
DACL
DALEN
DCB2
AUDIO/
VOICE
FILTERS
MIX
MODE1
DVFLT
MIXDAR
DACR
DAREN
Figure 23. Playback Level Control Block Diagram
Table 18. DAC Playback Level Control Register
REGISTER
BIT
NAME
7
DV1M/DV2M
5
DV1G
4
0x2F/0x31
2
DV1/DV2
0
DAI1/DAI2 Mute
0 = Disabled
1 = Enabled
DAI1 Voice Mode Gain
DV1G only applies when MODE1 = 0.
00 = 0dB
01 = 6dB
10 = 12dB
11 = 18dB
DAI1/DAI2 Attenuation
3
1
DESCRIPTION
VALUE
GAIN (dB)
VALUE
0x0
0
0x8
GAIN (dB)
-8
0x1
-1
0x9
-9
0x2
-2
0xA
-10
0x3
-3
0xB
-11
0x4
-4
0xC
-12
0x5
-5
0xD
-13
0x6
-6
0xE
-14
0x7
-7
0xF
-15
���������������������������������������������������������������� Maxim Integrated Products 91
MAX98088
Stereo Audio Codec
with FlexSound Technology
DAC Input Mixers
The IC’s stereo DAC accepts input from two digital audio paths. The DAC mixer routes any audio path to the left and
right DACs (Figure 24).
DV1G:
0/6/12/18dB
+
MULTI BAND ALC
DVEQ1:
0dB TO -15dB
5-BAND
PARAMETRIC
EQ
DVEQ2:
0dB TO -15dB
5-BAND
PARAMETRIC
EQ
EQ1EN
EQ2EN
EXCURSION LIMITER
DV2:
0dB TO -15dB
DV1:
0dB TO -15dB
MIX
AUDIO/
FILTERS
MIXDAL
DACL
DALEN
DCB2
AUDIO/
VOICE
FILTERS
MODE1
DVFLT
MIX
MIXDAR
DACR
DAREN
Figure 24. DAC Input Mixer Block Diagram
Table 19. DAC Input Mixer Register
REGISTER
BIT
NAME
7
6
5
0x22
MIXDAL
Left DAC Input Mixer
1xxx = DAI1 left channel
x1xx = DAI1 right channel
xx1x = DAI2 left channel
xxx1 = DAI2 right channel
MIXDAR
Right DAC Input Mixer
1xxx = DAI1 left channel
x1xx = DAI1 right channel
xx1x = DAI2 left channel
xxx1 = DAI2 right channel
4
3
2
1
0
DESCRIPTION
���������������������������������������������������������������� Maxim Integrated Products 92
MAX98088
Stereo Audio Codec
with FlexSound Technology
Receiver Amplifier
The IC includes a single differential receiver amplifier. The receiver amplifier is designed to drive a 32I earpiece
speaker. In cases where a single transducer is used for the loudspeaker and receiver, use the SPKBYP switch to route
the receiver amplifier output to the left speaker outputs. The receiver amplifier can also be configured as stereo singleended line outputs using the I2C interface.
RECVOLL:
+8dB TO -62dB
RECP/
LOUTL/
RXINP
0dB
MIX
RECLEN
MIXRECL
RECBYP
RECVOLR:
+8dB TO -62dB
MIX
0dB
LINEMODE
RECREN
MIXRECR
RECN/
LOUTR/
RXINN
SPKBYP
SPKLP
+6dB
SPKLN
SPLEN
DACL
DALEN
DACR
DAREN
Figure 25. Receiver Amplifier Block Diagram
���������������������������������������������������������������� Maxim Integrated Products 93
MAX98088
Stereo Audio Codec
with FlexSound Technology
Receiver Output Mixer
The IC’s receiver amplifier accepts input from the stereo DAC, the line inputs (single-ended or differential), and the MIC
inputs. Configure the mixer to mix any combination of the available sources. When more than one signal is selected, the
mixed signal can be configured to attenuate 6dB, 9dB, or 12dB.
Table 20. Receiver Output Mixer Register
REGISTER
BIT
NAME
7
MIXRECL
MIXRECR
Right Receiver Output Mixer
1xxxxxxx = Left DAC
x1xxxxxx = MIC2
xx1xxxxx = MIC1
xxx1xxxx = INB2 (INBDIFF = 0) or INB2-INB1 (INBDIFF = 1)
xxxx1xxx = INB1
xxxxx1xx = INA2 (INADIFF = 0) or INA2-INA1 (INADIFF = 1)
xxxxxx1x = INA1
xxxxxxx1 = Right DAC
6
5
0x28
4
3
2
1
0
7
6
5
0x29
4
3
2
1
0
7
3
0x2A
2
LINE_MODE
0
Receiver Output Mode. Configures receive path output mode between BTL and stereo line output.
0 = BTL
1 = Stereo line output
MIXRECR
_GAIN
Right Receiver Mixer Gain Select
00 = 0dB
01 = -6dB
10 = -9dB
11 = -12dB
MIXRECL
_GAIN
Left Receiver Mixer Gain Select
00 = 0dB
01 = -6dB
10 = -9dB
11 = -12dB
1
0
DESCRIPTION
Left Receiver Output Mixer
1xxxxxxx = Right DAC
x1xxxxxx = MIC2
xx1xxxxx = MIC1
xxx1xxxx = INB2 (INBDIFF = 0) or INB2-INB1 (INBDIFF = 1)
xxxx1xxx = INB1
xxxxx1xx = INA2 (INADIFF = 0) or INA2-INA1 (INADIFF = 1)
xxxxxx1x = INA1
xxxxxxx1 = Left DAC
���������������������������������������������������������������� Maxim Integrated Products 94
MAX98088
Stereo Audio Codec
with FlexSound Technology
Receiver Output Volume
Table 21. Receiver Output Level Register
REGISTER
BIT
NAME
7
RECLM/
RECRM
3
2
1
0
Receiver Output Mute
0 = Disabled
1 = Enabled
Receiver Output Volume Level
4
0x3B/0x3C
DESCRIPTION
RECVOLL/
RECVOLR
VALUE
VOLUME (dB)
VALUE
VOLUME (dB)
0x00
-62
0x10
-10
0x01
-58
0x11
-8
0x02
-54
0x12
-6
0x03
-50
0x13
-4
0x04
-46
0x14
-2
0x05
-42
0x15
0
0x06
-38
0x16
+1
0x07
-35
0x17
+2
0x08
-32
0x18
+3
0x09
-29
0x19
+4
0x0A
-26
0x1A
+5
0x0B
-23
0x1B
+6
0x0C
-20
0x1C
+6.5
0x0D
-17
0x1D
+7
0x0E
-14
0x1E
+7.5
0x0F
-12
0x1F
+8
���������������������������������������������������������������� Maxim Integrated Products 95
MAX98088
Stereo Audio Codec
with FlexSound Technology
Speaker Amplifiers
The IC integrates a stereo filterless Class D amplifier that
offers much higher efficiency than Class AB without the
typical disadvantages.
The high efficiency of a Class D amplifier is due to the
switching operation of the output stage transistors. In a
Class D amplifier, the output transistors act as current
steering switches and consume negligible additional
power. Any power loss associated with the Class D output stage is mostly due to the I2R loss of the MOSFET
on-resistance, and quiescent current overhead.
The theoretical best efficiency of a linear amplifier is 78%,
however, that efficiency is only exhibited at peak output
power. Under normal operating levels (typical music
reproduction levels), efficiency falls below 30%, whereas
the IC’s Class D amplifier still exhibits 80% efficiency
under the same conditions.
Traditional Class D amplifiers require the use of external LC filters or shielding to meet EN55022B and FCC
electromagnetic-interference (EMI) regulation standards.
Maxim’s patented active emissions limiting edge-rate
control circuitry reduces EMI emissions, allowing operation without any output filtering in typical applications.
SPKLVDD
SPVOLL:
+8dB TO -62dB
MIX
SPKLN
SPLEN
DACL
DALEN
SPKLP
+6dB
SPKLGND
POWER/
DISTORTION LIMITER
MIXSPL
SPKRVDD
SPKRP
DACR
+6dB
MIX
DAREN
MIXSPR
SPVOLR:
+8dB TO -62dB
SPKRN
SPREN
SPKRGND
Figure 26. Speaker Amplifier Path Block Diagram
���������������������������������������������������������������� Maxim Integrated Products 96
MAX98088
Stereo Audio Codec
with FlexSound Technology
Speaker Output Mixers
The IC’s speaker amplifiers accept input from the stereo DAC, the line inputs (single-ended ore differential), and the MIC inputs.
Configure the mixer to mix any combination of the available sources. When more than one signal is selected, the mixer can
be configured to attenuate the signal by 6dB, 9dB or 12dB.
Table 22. Speaker Output Mixer Register
REGISTER
BIT
NAME
7
MIXSPL
MIXSPR
Right Speaker Output Mixer
1xxxxxxx = Left DAC
x1xxxxxx = MIC2
xx1xxxxx = MIC1
xxx1xxxx = INB2 (INBDIFF = 0) or INB2-INB1 (INBDIFF = 1)
xxxx1xxx = INB1
xxxxx1xx = INA2 (INADIFF = 0) or INA2-INA1 (INADIFF = 1)
xxxxxx1x = INA1
xxxxxxx1 = Right DAC
MIXSPR
_GAIN
Right Speaker Mixer Gain Select
00 = 0dB
01 = -6dB
10 = -9dB
11 = -12dB
MIXSPL
_GAIN
Left Speaker Mixer Gain Select
00 = 0dB
01 = -6dB
10 = -9dB
11 = -12dB
6
5
0x2B
4
3
2
1
0
7
6
5
0x2C
4
3
2
1
0
3
2
0x2D
1
0
DESCRIPTION
Left Speaker Output Mixer
1xxxxxxx = Right DAC
x1xxxxxx = MIC2
xx1xxxxx = MIC1
xxx1xxxx = INB2 (INBDIFF = 0) or INB2-INB1 (INBDIFF = 1)
xxxx1xxx = INB1
xxxxx1xx = INA2 (INADIFF = 0) or INA2-INA1 (INADIFF = 1)
xxxxxx1x = INA1
xxxxxxx1 = Left DAC
���������������������������������������������������������������� Maxim Integrated Products 97
MAX98088
Stereo Audio Codec
with FlexSound Technology
Speaker Output Volume
Table 23. Speaker Output Level Register
REGISTER
BIT
7
NAME
SPLM/SPRM
DESCRIPTION
Left/Right Speaker Output Mute
0 = Disabled
1 = Enabled
Left/Right Speaker Output Volume Level
4
0x3D/0x3E
3
SPVOLL/SPVOLR
2
1
VALUE
VOLUME (dB)
VALUE
VOLUME (dB)
0x00
-62
0x10
-10
0x01
-58
0x11
-8
0x02
-54
0x12
-6
0x03
-50
0x13
-4
0x04
-46
0x14
-2
0x05
-42
0x15
0
0x06
-38
0x16
+1
0x07
-35
0x17
+2
0x08
-32
0x18
+3
0x09
-29
0x19
+4
0x0A
-26
0x1A
+5
0x0B
-23
0x1B
+6
0x0C
-20
0x1C
+6.5
0x0D
-17
0x1D
+7
0x0E
-14
0x1E
+7.5
0x0F
-12
0x1F
+8
Speaker Amplifier Signal Processing
The IC includes signal processing to improve the sound
quality of the speaker output and protect transducers
from damage. An excursion limiter dynamically adjusts
the highpass corner frequency, while a power limiter and
distortion limiter prevent the amplifier from outputting too
much distortion or power. The excursion limiter is located
in the DSP while the distortion limiter and power limiter
control the analog volume control (Figure 28). All three
limiters analyze the speaker amplifier’s output signal to
determine when to take action.
Excursion Limiter
The excursion limiter is a dynamic highpass filter that
monitors the speaker outputs and increases the highpass
corner frequency when the speaker amplifier’s output
exceeds a predefined threshold. The filter smoothly
transitions between the high and low corner frequency to
prevent unwanted artifacts. The filter can operate in four
different modes:
U Fixed-Frequency Preset Mode. The highpass corner
frequency is fixed at the upper corner frequency and
does not change with signal level.
U Fixed-Frequency Programmable Mode. The highpass corner frequency is fixed to that specified by the
programmable biquad filter.
U Preset Dynamic Mode. The highpass filter automatically slides between a preset upper and lower corner
frequency based on output signal level.
U User-Programmable Dynamic Mode. The highpass
filter slides between a user-programmed biquad filter
on the low side to a predefined corner frequency on
the high side.
���������������������������������������������������������������� Maxim Integrated Products 98
MAX98088
Stereo Audio Codec
with FlexSound Technology
The transfer function for the user-programmable biquad is:
b + b1z -1 + b 2z -2
H(z) = 0
1 + a 1z -1 + a 2z -2
The MAX98088 EV kit software includes a graphic interface
for generating the user-programmable biquad coefficients.
Note: Only change the excursion limiter settings when
the signal path is disabled to prevent undesired artifacts.
The coefficients b0, b1, b2, a1, and a2 are sample
rate dependent and stored in registers 0xB4 through
0xC7. Store b0, b1, and b2 as positive numbers. Store
a1 and a2 as negated two’s complement numbers.
Separate filters can be stored for the DAI1 and DAI2
playback paths.
DV1G:
0/6/12/18dB
+
MULTI BAND ALC
DVEQ1:
0dB TO -15dB
5-BAND
PARAMETRIC
EQ
DVEQ2:
0dB TO -15dB
SPVOLL:
+8dB TO -62dB
5-BAND
PARAMETRIC
EQ
EQ1EN
MIX
SPKLN
SPKLGND
MIXSPL
EXCURSION LIMITER
MIX
AUDIO/
FILTERS
MIXDAL
POWER/
DISTORTION LIMITER
DACL
SPKRVDD
DALEN
SPKRP
DCB2
MIX
SPVOLR:
MIXSPR +8dB TO -62dB
DV1:
0dB TO -15dB
SPKLP
+6dB
SPLEN
EQ2EN
DV2:
0dB TO -15dB
SPKLVDD
+6dB
SPKRN
SPREN
SPKRGND
AUDIO/
VOICE
FILTERS
MODE1
DVFLT
MIX
MIXDAR
DACR
DAREN
Figure 27. Speaker Amplifier Signal Processing Block Diagram
���������������������������������������������������������������� Maxim Integrated Products 99
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 24. Excursion Limiter Registers
REGISTER
BIT
NAME
6
5
DHPUCF
4
0x41
1
DHPLCF
0
6
0x43
5
ALCRLS
4
3
2
0x42
DHPTH
1
0
DESCRIPTION
Excursion Limiter Corner Frequency
The excursion limiter has limited sliding range and minimum corner frequencies. Listed
below are all the valid filter combinations.
LOWER CORNER UPPER CORNER
MINIMUM BIQUAD
DHPUCF DHPLCF
FREQUENCY
FREQUENCY
CORNER FREQUENCY
Excursion limiter disabled
—
000
00
400Hz
—
001
00
600Hz
—
010
00
800Hz
—
011
00
1kHz
—
100
00
Programmable using biquad
100Hz
000
11
200Hz
400Hz
—
001
01
400Hz
600Hz
—
010
10
400Hz
800Hz
—
011
10
Programmable
400Hz
200Hz
001
11
using biquad
Programmable
using biquad
600Hz
300Hz
010
11
Programmable
using biquad
800Hz
400Hz
011
11
Programmable
using biquad
1kHz
500Hz
100
11
ALC and Excursion Limiter Release Time
Sets the release time for both the ALC and Excursion Limiter. See the Automatic Level
Control section for ALC release times. Excursion limiter release time is defined as the
time required to slide from the high corner frequency to the low corner frequency.
VALUE
EXCURSION LIMITER RELEASE TIME (s)
000
4
001
2
010
1
011
0.5
100
0.25
101
0.25
110
Reserved
111
Reserved
Excursion Limiter Threshold
Measured at the Class D speaker amplifier outputs. Signals above the threshold use
the upper corner frequency. Signals below the threshold use the lower corner frequency. VBAT must correctly reflect the voltage of SPKLVDD to achieve accurate
thresholds.
000 = 0.34VP
001 = 0.71VP
010 = 1.30VP
011 = 1.77VP
100 = 2.33VP
101 = 3.25VP
110 = 4.25VP
111 = 4.95VP
��������������������������������������������������������������� Maxim Integrated Products 100
MAX98088
Stereo Audio Codec
with FlexSound Technology
Power Limiter
The IC’s power limiter tracks the continuous power delivered to the loudspeaker and briefly mutes the speaker
amplifier output if the speaker is at risk of sustaining
permanent damage.
Loudspeakers are typically damaged when the voice coil
overheats due to extended operation above the rated
power. During normal operation, heat generated in the
voice coil is transferred to the speaker’s magnet, which
transfers heat to the surrounding air. For the voice coil
to overheat, both the voice coil and the magnet must
overheat. The result is that a loudspeaker can operate
above its rated power for a significant time before it heats
sufficiently to cause damage.
The IC’s power limiter includes user-programmable time
constants and power thresholds to match a wide range
of loudspeakers. Program the power limiter’s threshold to
match the loudspeaker’s rated power handling. This can
be determined through measurement or the loudspeaker’s specification. Program time constant 1 to match the
voice coil’s thermal time constant. Program time constant
2 to match the magnet’s thermal time constant. The time
constants can be determined by plotting the voice coil’s
resistance vs. time as power is applied to the speaker.
Table 25. Power Limiter Registers
REGISTER
BIT
NAME
DESCRIPTION
Power Limiter Threshold
If the continuous output power from the speaker amplifiers exceeds this threshold,
the output is briefly muted to protect the speaker. The threshold is measured in watts
assuming an 8I load. VBAT must correctly reflect the voltage of SPKLVDD/
SPKRVDD to achieve accurate thresholds.
7
VALUE
THRESHOLD
(W)
VALUE
THRESHOLD
(W)
0x0
Power limiter
disabled
0x8
0.27
0x1
0.05
0x9
0.35
0x2
0.06
0xA
0.48
0x3
0.09
0xB
0.72
0x4
0.11
0xC
1.00
0x5
0.13
0xD
1.43
0x6
0.18
0xE
1.57
0x7
0.22
0xF
1.80
6
PWRTH
5
0x44
4
Power Limiter Weighting Factor
Determines the balance between time constant 1 and 2 to match the dominance of
each time constant in the loudspeaker.
2
1
0
PWRK
VALUE
T1 (%)
000
50
T2 (%)
50
001
62.5
37.5
010
75
25
011
87.5
12.5
100
100
0
101
12.5
87.5
110
25
75
111
37.5
62.5
��������������������������������������������������������������� Maxim Integrated Products 101
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 25. Power Limiter Registers (continued)
REGISTER
BIT
NAME
7
6
PWRT2
5
4
0x45
2
PWRT1
0
VALUE
TIME CONSTANT
(min)
VALUE
TIME CONSTANT
(min)
0x0
Disabled
0x8
3.75
0x1
0.50
0x9
5.00
0x2
0.67
0xA
6.66
0x3
0.89
0xB
8.88
0x4
1.19
0xC
Reserved
0x5
1.58
0xD
Reserved
0x6
2.11
0xE
Reserved
0x7
2.81
0xF
Reserved
Power Limiter Time Constant 1
Select a value that matches the thermal time constant of the loudspeaker’s voice coil.
3
1
DESCRIPTION
Power Limiter Time Constant 2
Select a value that matches the thermal time constant of the loudspeaker’s magnet.
VALUE
TIME CONSTANT
(s)
VALUE
TIME CONSTANT
(s)
0x0
Disabled
0x8
3.75
0x1
0.50
0x9
5.00
0x2
0.67
0xA
6.66
0x3
0.89
0xB
8.88
0x4
1.19
0xC
Reserved
0x5
1.58
0xD
Reserved
0x6
2.11
0xE
Reserved
0x7
2.81
0xF
Reserved
Distortion Limiter
The IC’s distortion limiter ensures that the speaker amplifier’s output does not exceed the programmed THD+N limit.
The distortion limiter analyzes the Class D output duty cycle to determine the percentage of the waveform that is
clipped. If the distortion exceeds the programmed threshold, the output gain is reduced.
��������������������������������������������������������������� Maxim Integrated Products 102
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 26. Distortion Limiter Registers
REGISTER
BIT
NAME
7
6
5
THDCLP
0x46
4
0
DESCRIPTION
Distortion Limit
Measured in % THD+N.
THDT1
VALUE
THD+N LIMIT (%)
VALUE
THD+N LIMIT (%)
0x0
Limiter disabled
0x8
12
0x1
<1
0x9
14
0x2
1
0xA
16
0x3
2
0xB
18
0x4
4
0xC
20
0x5
6
0xD
21
0x6
8
0xE
22
0x7
10
0xF
24
Distortion Limiter Release Time Constant
Duration of time required for the speaker amplifier’s output gain to adjust back to the
nominal level after a large signal has passed.
0 = 1.4s
1 = 2.8s
Headphone
DirectDrive Headphone Amplifier
Traditional single-supply headphone amplifiers have
outputs biased at a nominal DC voltage (typically half
the supply). Large coupling capacitors are needed to
block this DC bias from the headphone. Without these
capacitors, a significant amount of DC current flows to
the headphone, resulting in unnecessary power dissipation and possible damage to both headphone and
headphone amplifier.
Maxim’s second-generation DirectDrive architecture
uses a charge pump to create an internal negative supply voltage. This allows the headphone outputs of the ICs
to be biased at GND while operating from a single supply
(Figure 28). Without a DC component, there is no need
for the large DC-blocking capacitors. Instead of two large
(220µF typ) capacitors, the IC’s charge pump requires
3 small ceramic capacitors, conserving board space,
reducing cost, and improving the frequency response of
the headphone amplifier.
Charge Pump
The dual-mode charge pump generates both the positive
and negative power supply for the headphone amplifier.
To maximize efficiency, both the charge pump’s switching
frequency and output voltage change based on signal
level.
When the input signal level is less than 10% of PVDD,
the switching frequency is reduced to a low rate. This
minimizes switching losses in the charge pump. When
the input signal exceeds 10% of PVDD, the switching fre­
quency increases to support the load current.
For input signals below 25% of PVDD, the charge pump
generates Q(PVDD/2) to minimize the voltage drop
across the amplifier’s power stage and thus improve
efficiency. Input signals that exceed 25% of PVDD cause
the charge pump to output QPVDD. The higher output
voltage allows for full output power from the headphone
amplifier.
To prevent audible gliches when transitioning from the
Q(PVDD/2) output mode to the QPVDD output mode, the
charge pump transitions very quickly. This quick change
draws significant current from PVDD for the duration of
the transition. The bypass capacitor on PVDD supplies
the required current and prevents droop on PVDD.
The charge pump’s dynamic switching mode can be
turned off through the I2C interface. The charge pump
can then be forced to output either Q(PVDD/2) or QPVDD
regardless of input signal level.
��������������������������������������������������������������� Maxim Integrated Products 103
MAX98088
Stereo Audio Codec
with FlexSound Technology
VDD
VDD/2
Class H Operation
A Class H amplifier uses a Class AB output stage with
power supplies that are modulated by the output signal.
In the case of the ICs, two nominal power-supply differentials of 1.8V (+0.9V to -0.9V) and 3.6V (+1.8V to -1.8V)
are available from the charge pump. Figure 29 shows the
operation of the output-voltage-dependent power supply
GND
CONVENTIONAL AMPLIFIER BIASING SCHEME
+VDD
1.8V
0.9V
32ms
HPVDD
VTH_H
OUTPUT
VOLTAGE
GND
VTH_L
-0.9V
HPVSS
32ms
-1.8V
-VDD
(VSS)
DirectDrive AMPLIFIER BIASING SCHEME
Figure 28. Traditional Amplifier Output vs. DirectDrive Output
Figure 29. Class H Operation
DACL
DALEN
DACR
DAREN
MIXHPL_
PATH SEL
HPVOLL:
+3dB TO -67dB
MIX
HPLEN
MIXHPL
MIX
MIXHPR
HPL
HPSNS
MIXHPR_
PATH SEL
HPVOLR:
+3dB TO -67dB
HPR
HPREN
Figure 30. Headphone Amplifier Block Diagram
��������������������������������������������������������������� Maxim Integrated Products 104
MAX98088
Stereo Audio Codec
with FlexSound Technology
Headphone Output Mixers
The headphone amplifier mixer accepts input from the
stereo DAC, the line inputs (single-ended or differential),
and the MIC inputs. Configure the mixer to mix any combination of the available sources. When more than one
signal is selected, the mixer can be configured to attenuate the signal by 6dB, 9dB, or 12dB. The stereo DAC
can bypass the headphone mixers, and be connected
directly to the headphone amplifiers to provide lower
power consumption.
Table 27. Headphone Output Mixer Register
REGISTER
BIT
NAME
7
6
5
0x25
4
3
MIXHPL
2
1
0
7
6
5
0x26
4
3
MIXHPR
2
1
0
0x27
5
MIXHPR_ PATH
SEL
4
MIXHPL_ PATH
SEL
3
2
MIXHPR
_GAIN
1
0
MIXHPL
_GAIN
DESCRIPTION
Left Headphone Output Mixer
1xxxxxxx = Right DAC
x1xxxxxx = MIC2
xx1xxxxx = MIC1
xxx1xxxx = INB2 (INBDIFF = 0) or INB2-INB1 (INBDIFF = 1)
xxxx1xxx = INB1
xxxxx1xx = INA2 (INADIFF = 0) or INA2-INB1 (INADIFF = 1)
xxxxxx1x = INA1
xxxxxxx1 = Left DAC
Right Headphone Output Mixer
1xxxxxxx = Left DAC
x1xxxxxx = MIC2
xx1xxxxx = MIC1
xxx1xxxx = INB2 (INBDIFF = 0) or INB2-INB1 (INBDIFF = 1)
xxxx1xxx = INB1
xxxxx1xx = INA2 (INADIFF = 0) or INA2-INA1 (INADIFF = 1)
xxxxxx1x = INA1
xxxxxxx1 = Right DAC
Right Headphone Mixer Path Select
0 = Directly connect to the right DAC (bypass right headphone output mixer)
1 = Right headphone output mixer
Left Headphone Mixer Path Select
0 = Directly connect to the left DAC (bypass left headphone output mixer)
1 = Left headphone output mixer
Right Headphone Mixer Gain Select
00 = 0dB
01 = -6dB
10 = -9dB
11 = -12dB
Left Headphone Mixer Gain Select
00 = 0dB
01 = -6dB
10 = -9dB
11 = -12dB
��������������������������������������������������������������� Maxim Integrated Products 105
MAX98088
Stereo Audio Codec
with FlexSound Technology
Headphone Output Volume
Table 28. Headphone Output Level Register
REGISTER
BIT
NAME
7
HPLM/HPRM
DESCRIPTION
Headphone Output Mute
0 = Disabled
1 = Enabled
Left/Right Headphone Output Volume Level
4
0x39/0x3A
3
HPVOLL/HPVOLR
2
1
0
VALUE
VOLUME (dB)
VALUE
VOLUME (dB)
0x00
-67
0x10
-15
0x01
-63
0x11
-13
0x02
-59
0x12
-11
0x03
-55
0x13
-9
0x04
-51
0x14
-7
0x05
-47
0x15
-5
0x06
-43
0x16
-4
0x07
-40
0x17
-3
0x08
-37
0x18
-2
0x09
-34
0x19
-1
0x0A
-31
0x1A
0
0x0B
-28
0x1B
+1
0x0C
-25
0x1C
+1.5
0x0D
-22
0x1D
+2
0x0E
-19
0x1E
+2.5
0x0F
-17
0x1F
+3
��������������������������������������������������������������� Maxim Integrated Products 106
MAX98088
Stereo Audio Codec
with FlexSound Technology
Output Bypass Switches
an external receiver amplifier is used, route its output to
the left speaker through RECP/RXINP and RECN/RXINN,
bypassing the Class D amplifier. In systems where an
external amplifier drives both the receiver and the IC’s
line input, one of the differential signals can be disconnected from the receiver when not needed by passing it
through the analog switch that connects RECP/RXINP to
RECN/RXINN.
The IC includes two output bypass switches that solve
common applications problems. When a single transducer is used for the loudspeaker and receiver, the need
exists for two amplifiers to power the same transducer.
Bypass switches connect the IC’s receiver amplifier
output to the speaker amplifier’s output, allowing either
amplifier to power the same transducer. In systems where
RECP/RXINP
0dB
10I*
RECLEN
RECN/RXINN
0dB
RECREN
RECP/RXINP
0dB
10I*
EXTERNAL
RECEIVER
AMP
RECLEN
RECLEN
RECN/RXINN
0dB
RECBYP
RECREN
SPKBYP
SPLEN
RECREN
SPKBYP
RECBYP
SPKBYP
SPKLVDD
SPKLP
SPKLVDD
SPKLP
SPKLN
+6dB
SPKLN
+6dB
SPKLGND
SPLEN
SPKLGND
SPLEN
POWER/DISTORTION
LIMITER
EXTERNAL
RECEIVER
AMP
RECN/RXINN
0dB
RECBYP
SPKLVDD
SPKLP
+6dB
RECP/RXINP
0dB
POWER/DISTORTION
LIMITER
SPKLN
SPKLGND
POWER/DISTORTION
LIMITER
*OPTIONAL 10I RESISTORS IMPROVE DISTORTION
THROUGH THE ANALOG SWITCH.
SPEAKER AMPLIFIER BYPASS USING AN
EXTERNAL RECEIVER AMPLIFIER
SPEAKER AMPLIFIER BYPASS USING THE
INTERNAL RECEIVER AMPLIFIER
CONTROLLING AN EXTERNAL RECEIVE
AMPLIFIER AND SPEAKER
Figure 31. Output Bypass Switch Block Diagrams
Table 29. Output Bypass Switches Register
REGISTER
BIT
NAME
7
INABYP
4
MIC2BYP
1
See the Microphone Inputs section.
RECBYP
RXINP to RXINN Bypass Switch
Shorts RXINP to RXINN allowing a signal to pass through the ICs. Disable the receiver
amplifier when RECBYP = 1.
0 = Disabled
1 = Enabled
SPKBYP
RXIN to SPKL Bypass Switch
Shorts RXINP/RXINN to SPKLP/SPKLN allowing either the internal or an external receiver amplifier to power the left speaker. Disable the left speaker amplifier when SPKBYP
= 1.
0 = Disabled
1 = Enabled
0x4A
0
DESCRIPTION
��������������������������������������������������������������� Maxim Integrated Products 107
MAX98088
Stereo Audio Codec
with FlexSound Technology
Click-and-Pop Reduction
The IC includes extensive click-and-pop reduction circuitry. The circuitry minimizes clicks and pops at turn-on,
turn-off, and during volume changes.
Zero-crossing detection is implemented on all analog
PGAs and volume controls to prevent large glitches when
volume changes are made. Instead of making a volume
change immediately, the change is made when the audio
signal crosses the midpoint. If no zero-crossing occurs
within the timeout window, the change is forced.
Volume slewing breaks up large volume changes into the
smallest available step size and the steps through each
step between the initial and final volume setting. When
enabled, volume slewing also occurs at device turn-on
and turn-off. During turn-on the volume is set to mute
before the output is enabled. Once the output is on, the
volume ramps to the desired level. At turn-off the volume
is ramped to mute before the outputs are disabled.
When there is no audio signal zero-crossing detection
can prevent volume slewing from occurring. Enable
enhanced volume slewing to prevent the volume controller from requesting another volume level until the previous one has been set. Each step in the volume ramp then
occurs after a zero crossing has occurred in the audio
signal or the timeout window has expired. During turn-off,
enhance volume slewing is always disabled.
Table 30. Click-and-Pop Reduction Register
REGISTER
BIT
NAME
DESCRIPTION
VS2EN
Enhanced Volume Smoothing
During volume slewing, the controller waits for each step in the ramp to be applied
before sending the next step. When zero-crossing detection is enabled this prevents
large steps in the output volume when no zero crossings are detected.
0 = Enabled
1 = Disabled
Applies to volume changes in HPVOLL, HPVOLR, RECVOL, SPVOLL, and SPVOLR.
VSEN
Volume Adjustment Smoothing
Volume changes are smoothed by stepping through intermediate steps. Also ramps
the volume from minimum to the programmed value at turn-on and back to minimum at
turn-off.
0 = Enabled
1 = Disabled
Applies to volume changes in HPVOLL, HPVOLR, RECVOL, SPVOLL, and SPVOLR.
5
ZDEN
Zero-Crossing Detection
Holds volume changes until there is a zero crossing in the audio signal. This reduces
click and pop during volume changes (zipper noise). If no zero crossing is detected
within 100ms, the volume change is forced.
0 = Enabled
1 = Disabled
Applies to volume changes in PGAM1, PGAM2, PGAOUTA, PGAOUTB, PGAOUTC,
HPVOLL, HPVOLR, RECVOL, SPVOLL, and SPVOLR.
1
EQ2EN
0
EQ1EN
7
6
0x47
See the 5-Band Parametric EQ section.
��������������������������������������������������������������� Maxim Integrated Products 108
MAX98088
Stereo Audio Codec
with FlexSound Technology
Jack Detection
The IC features jack detection that can detect the insertion and removal of a jack. When a jack is detected, an
interrupt on IRQ can be triggered to alert the microcontroller of the event. Figure 32 shows the typical configuration for jack detection.
Jack Detection and Removal
When the IC is in normal operation and the MICBIAS is
enabled, jack insertion and removal can be detected
through JACKSNS. To detect a jack insertion and
removal, the ICs must be powered on and MICBIAS
enabled. Set JDETEN, MBEN, BIASEN, and VCMEN bits
to enable jack detection circuitry. JACKSNS is pulled up
by MICBIAS as long as no load is applied to JACKSNS.
Table 31 shows the change in JKSNS that occurs when
a jack is inserted and removed.
HPL
MICBIAS
JACKSNS
HPR
MIC1P
Figure 32. Typical Configuration for Jack Detection
Table 31. Change in JKSNS Upon Jack Insertion
JACK TYPE
MBEN = 1, BIASEN = 1, VCMEN = 1
GND
GND
R
L
JKSNS: 1 è 0
MIC
GND
R
L
JKSNS: 1 è 0
Table 32. Change in JKSNS Upon Jack Removal
JACK TYPE
MBEN = 1, BIASEN = 1, VCMEN = 1
GND
GND
R
L
JKSNS: 0 è 1
MIC
GND
R
L
JKSNS: 0 è 1
��������������������������������������������������������������� Maxim Integrated Products 109
MAX98088
Stereo Audio Codec
with FlexSound Technology
Table 33. Jack Detection Registers
REGISTER
0x02
(Read Only)
0x4B
BIT
NAME
6
JKSNS
7
JDETEN
1
JDEB
0
DESCRIPTION
JACKSNS State
Reports the status of JACKSNS when JDETEN = 1, MBEN = 1, BIASEN = 1, and
VCMEN = 1.
0 = JACKSNS low
1 = JACKSNS high
Jack Detection Enable
0 = Disabled
1 = Enabled
Jack Detection Debounce
Configures the debounce time for setting JDET.
00 = 25ms
01 = 50ms
10 = 100ms
11 = 200ms
Battery Measurement
The IC measures the voltage applied to SPKLVDD (typically the battery voltage) and reports the value in register 0x03.
This value is also used by the speaker limiter circuitry to set accurate thresholds. When the battery measurement function is disabled, the battery voltage is user programmable.
Table 34. Battery Measurement Registers
REGISTER
BIT
NAME
DESCRIPTION
VBAT
Battery Voltage
Read VBAT when VBATEN = 1 to determine VSPKLVDD. Program VBAT when VBATEN
= 0 to allow proper speaker amplifier signal processing. Calculate/program the battery
voltage using the following formula:
VBATTERY = 2.55V + [VBAT/10]
7
SHDN
See the Power Management section.
6
VBATEN
3
PERFMODE
See the Power Management section.
2
HPPLYBCK
See the Power Management section.
1
PWRSV8K
See the Power Management section.
0
PWRSV
See the Power Management section.
4
3
0x03
2
1
0
0x51
Battery Measurement Enable. Enables an internal ADC to measure VSPKLVDD.
0 = Disabled (register 0x03 readable and writeable)
1 = Enabled (register 0x03 read only)
��������������������������������������������������������������� Maxim Integrated Products 110
MAX98088
Stereo Audio Codec
with FlexSound Technology
Device Status
The IC uses register 0x00 and IRQ to report the status of
various device functions. The status register bits are set
when their respective events occur, and cleared upon
reading the register. Device status can be determined
either by poling register 0x00 or configuring the IRQ to
pull low when specific events occur. IRQ is an open-drain
output that requires a pullup resistor for proper operation.
Register 0x0F determines which bits in the status register
trigger IRQ to pull low.
Table 35. Status and Interrupt Registers
REGISTER
BIT
NAME
DESCRIPTION
CLD
Full Scale
0 = All digital signals are less than full scale.
1 = The DAC or ADC signal path has reached or exceeded full scale. This typically
indicates clipping.
6
SLD
Volume Slew Complete
SLD reports that any of the programmable-gain arrays or volume controllers has completed slewing from a previous setting to a new programmed setting. If multiple gain
arrays or volume controllers are changed at the same time, the SLD flag is set after the
last volume slew completes. SLD also reports when the digital audio interface soft-start
or soft-stop process has completed. MCLK is required for proper SLD operation.
0 = No volume slewing sequences have completed since the status register was last
read.
1 = Volume slewing complete.
5
ULK
Digital Audio Interface Unlocked
0 = Both digital audio interfaces are operating normally.
1 = Either digital audio interface is configured incorrectly or receiving invalid clocks.
1
JDET
Jack Configuration Change
JDET reports changes to any bit in the Jack Status register (0x02). Changes to the Jack
Status bits are debounced before setting JDET. The debounce period is programmable
using the JDEB bits. JDET is always set the first time JDETEN or SHDN is set the first
time power is applied to the IC. Read the status register following such an event to clear
JDET and allow for proper jack detection.
0 = No change in jack configuration.
1 = Jack configuration has changed.
7
ICLD
6
ISLD
5
IULK
1
IJDET
7
0x00
(Read Only)
0x0F
Full-Scale Interrupt Enable
0 = Disabled
1 = Enabled
Volume Slew Complete Interrupt Enable
0 = Disabled
1 = Enabled
Digital Audio Interface Unlocked Interrupt Enable
0 = Disabled
1 = Enabled
Jack Configuration Change Interrupt Enable
0 = Disabled
1 = Enabled
��������������������������������������������������������������� Maxim Integrated Products 111
MAX98088
Stereo Audio Codec
with FlexSound Technology
Device Revision
Table 36. Device Revision Register
REGISTER
BIT
NAME
DESCRIPTION
7
6
5
0xFF
(Read Only)
4
3
Device Revision Code
REV is always set to 0x40.
REV
2
1
0
I2C Serial Interface
The IC features an I2C/SMBusK-compatible, 2-wire
serial interface comprising a serial-data line (SDA) and
a serial-clock line (SCL). SDA and SCL facilitate communication between the IC and the master at clock rates
up to 400kHz. Figure 5 shows the 2-wire interface timing
diagram. The master generates SCL and initiates data
transfer on the bus. The master device writes data to the
IC by transmitting the proper slave address followed by
the register address and then the data word. Each transmit sequence is framed by a START (S) or REPEATED
START (Sr) condition and a STOP (P) condition. Each
word transmitted to the IC is 8 bits long and is followed
by an acknowledge clock pulse. A master reading data
from the IC transmits the proper slave address followed
by a series of nine SCL pulses. The IC transmits data on
SDA in sync with the master-generated SCL pulses. The
master acknowledges receipt of each byte of data. Each
read sequence is framed by a START or REPEATED
START condition, a not acknowledge, and a STOP condition. SDA operates as both an input and an open-drain
output. A pullup resistor, typically greater than 500I, is
required on SDA. SCL operates only as an input. A pullup
resistor, typically greater than 500I, is required on SCL
if there are multiple masters on the bus, or if the single
master has an open-drain SCL output. Series resistors
in line with SDA and SCL are optional. Series resistors
S
protect the digital inputs of the IC from high voltage
spikes on the bus lines, and minimize crosstalk and
undershoot of the bus signals.
Bit Transfer
One data bit is transferred during each SCL cycle. The
data on SDA must remain stable during the high period of
the SCL pulse. Changes in SDA while SCL is high are control signals (see the START and STOP Conditions section).
START and STOP Conditions
SDA and SCL idle high when the bus is not in use. A master initiates communication by issuing a START condition.
A START condition is a high-to-low transition on SDA with
SCL high. A STOP condition is a low-to-high transition on
SDA while SCL is high (Figure 33). A START condition
from the master signals the beginning of a transmission
to the IC. The master terminates transmission, and frees
the bus, by issuing a STOP condition. The bus remains
active if a REPEATED START condition is generated
instead of a STOP condition.
Early STOP Conditions
The IC recognizes a STOP condition at any point during
data transmission except if the STOP condition occurs in
the same high pulse as a START condition. For proper
operation, do not send a STOP condition during the same
SCL high pulse as the START condition.
Sr
P
SCL
SDA
Figure 33. START, STOP, and REPEATED START Conditions
SMBus is a trademark of Intel Corp.
��������������������������������������������������������������� Maxim Integrated Products 112
MAX98088
Stereo Audio Codec
with FlexSound Technology
Slave Address
The slave address is defined as the seven most significant bits (MSBs) followed by the read/write bit. For the
IC, the seven most significant bits are 0010000. Setting
the read/write bit to 1 (slave address = 0x21) configures
the IC for read mode. Setting the read/write bit to 0 (slave
address = 0x20) configures the ICs for write mode. The
address is the first byte of information sent to the IC after
the START condition.
Acknowledge
The acknowledge bit (ACK) is a clocked 9th bit that the
IC uses to handshake receipt each byte of data when
in write mode (Figure 34). The IC pulls down SDA during the entire master-generated 9th clock pulse if the
previous byte is successfully received. Monitoring ACK
allows for detection of unsuccessful data transfers. An
unsuccessful data transfer occurs if a receiving device
is busy or if a system fault has occurred. In the event
of an unsuccessful data transfer, the bus master retries
communication. The master pulls down SDA during the
9th clock cycle to acknowledge receipt of data when the
IC is in read mode. An acknowledge is sent by the master
after each read byte to allow data transfer to continue. A
not acknowledge is sent when the master reads the final
byte of data from the IC, followed by a STOP condition.
Write Data Format
A write to the IC includes transmission of a START condition, the slave address with the R/W bit set to 0, one byte
of data to configure the internal register address pointer,
one or more bytes of data, and a STOP condition. Figure 35
illustrates the proper frame format for writing one byte of
data to the IC. Figure 35 illustrates the frame format for
writing n-bytes of data to the IC.
CLOCK PULSE FOR
ACKNOWLEDGMENT
START
CONDITION
SCL
2
1
8
9
NOT ACKNOWLEDGE
SDA
ACKNOWLEDGE
Figure 34. Acknowledge
ACKNOWLEDGE FROM MAX98088
B7
ACKNOWLEDGE FROM MAX98088
S
SLAVE ADDRESS
B6
B5
B4
B3
B2
B1
B0
ACKNOWLEDGE FROM MAX98088
A
O
A
REGISTER ADDRESS
DATA BYTE
A
P
1 BYTE
R/W
AUTOINCREMENT INTERNAL REGISTER ADDRESS POINTER
Figure 35. Writing One Byte of Data to the ICs
ACKNOWLEDGE FROM MAX98088
ACKNOWLEDGE FROM MAX98088
S
SLAVE ADDRESS
B7 B6 B5 B4 B3 B2 B1 B0
ACKNOWLEDGE FROM MAX98088
O
A
REGISTER ADDRESS
R/W
ACKNOWLEDGE FROM MAX98088
A
DATA BYTE 1
1 BYTE
B7 B6 B5 B4 B3 B2 B1 B0
A
DATA BYTE n
A
P
1 BYTE
AUTOINCREMENT INTERNAL REGISTER ADDRESS POINTER
Figure 36. Writing n-Bytes of Data to the ICs
��������������������������������������������������������������� Maxim Integrated Products 113
MAX98088
Stereo Audio Codec
with FlexSound Technology
The slave address with the R/W bit set to 0 indicates
that the master intends to write data to the ICs. The ICs
acknowledge receipt of the address byte during the
master-generated 9th SCL pulse.
The first byte transmitted from the ICs is the content of
register 0x00. Transmitted data is valid on the rising
edge of SCL. The address pointer autoincrements after
each read data byte. This autoincrement feature allows
all registers to be read sequentially within one continuous
frame. A STOP condition can be issued after any number
of read data bytes. If a STOP condition is issued followed
by another read operation, the first data byte to be read
is from register 0x00.
The second byte transmitted from the master configures
the IC’s internal register address pointer. The pointer tells
the IC where to write the next byte of data. An acknowledge pulse is sent by the ICs upon receipt of the address
pointer data.
The address pointer can be preset to a specific register
before a read command is issued. The master presets the address pointer by first sending the IC’s slave
address with the R/W bit set to 0 followed by the register
address. A REPEATED START condition is then sent followed by the slave address with the R/W bit set to 1. The
IC then transmits the contents of the specified register.
The address pointer autoincrements after transmitting the
first byte.
The third byte sent to the ICs contains the data that is
written to the chosen register. An acknowledge pulse
from the ICs signals receipt of the data byte. The address
pointer autoincrements to the next register address after
each received data byte. This autoincrement feature
allows a master to write to sequential registers within one
continuous frame. The master signals the end of transmission by issuing a STOP condition. Register addresses
greater than 0xC7 are reserved. Do not write to these
addresses.
The master acknowledges receipt of each read byte during
the acknowledge clock pulse. The master must acknowledge all correctly received bytes except the last byte. The
final byte must be followed by a not acknowledge from the
master and then a STOP condition. Figure 37 illustrates
the frame format for reading one byte from the IC.Figure 38
illustrates the frame format for reading multiple bytes
from the ICs.
Read Data Format
Send the slave address with the R/W bit set to 1 to initiate a read operation. The IC acknowledges receipt of
its slave address by pulling SDA low during the 9th SCL
clock pulse. A START command followed by a read command resets the address pointer to register 0x00.
ACKNOWLEDGE FROM MAX98088
S
O
SLAVE ADDRESS
ACKNOWLEDGE FROM MAX98088
A
ACKNOWLEDGE FROM MAX98088
A
REGISTER ADDRESS
Sr
A
R/W
REPEATED START
R/W
1
SLAVE ADDRESS
NOT ACKNOWLEDGE FROM MASTER
DATA BYTE
A
P
1 BYTE
AUTOINCREMENT INTERNAL REGISTER ADDRESS POINTER
Figure 37. Reading One Byte of Data from the ICs
ACKNOWLEDGE FROM MAX98088
S
SLAVE ADDRESS
O
ACKNOWLEDGE FROM MAX98088
A
REGISTER ADDRESS
R/W
ACKNOWLEDGE FROM MAX98088
A
REPEATED START
Sr
SLAVE ADDRESS
1
R/W
A
DATA BYTE
A
1 BYTE
AUTOINCREMENT INTERNAL REGISTER ADDRESS POINTER
Figure 38. Reading n Bytes of Data from the ICs
��������������������������������������������������������������� Maxim Integrated Products 114
MAX98088
Stereo Audio Codec
with FlexSound Technology
Applications Information
Typical Operating Circuits
Figures 39 and 40 provide example operating circuits for the ICs. sThe external components shown are the minimum
required for the ICs to operate. Additional components may be required by the application.
2.8V TO 5.5V
1.8V
10FF
1.8V TO 3.6V
1FF
1.8V TO
5.5V
DVDDS1
DVDD
1FF
PVDD
1FF
AVDD
1.8V TO 3.6V
1FF
1FF
SPKLVDD
1FF
SPKRVDD
1FF
DVDDS2
10kI
TO MICROCONTROLLER
BCLKS2
IRQ
BCLKS1
DIGITAL AUDIO
PORT 1
I2C CONTROL
PORT
JACKSNS
1kI
2.2kI
SDINS2
LRCLKS1
SDOUTS2
SDINS1
JACKSNS
SDOUTS1
RECP/RXINP
SDA
RECN/RXINN
SCL
MICROPHONE
OUTPUT TO
BASEBAND
BYPASS
SWITCH
INPUT
8I
SPKLN
MAX98088
SPKRP
8I
SPKRN
MICBIAS
1FF
HPR
MIC2P
HEADSET
MICROPHONE
JACKSNS
SPKLP
MIC1P/DIGMICDATA
MIC1N/DIGMICCLK
DIGITAL
AUDIO
PORT 2
LRCLKS2
MCLK
10MHz TO 60MHz CLOCK INPUT
HPL
1FF
MIC2N
HPSNS
1FF
INA1/EXTMICP
HANDSET
MICROPHONE
1FF
REF
INA2/EXTMICN
1FF
REG
INB1
1kI
LINE INPUT
1FF
1FF
2.2FF
INB2
1FF
DGND AGND HPGND SPKRGND SPKLGND HPVDD
HPVSS
1FF
C1N
C1P
1FF
1FF
Figure 39. Typical Application Circuit Using Analog Microphone Inputs and the Bypass Switch
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MAX98088
Stereo Audio Codec
with FlexSound Technology
2.8V TO 5.5V
1.8V
10FF
1.8V TO 3.6V
1FF
1.8V TO
5.5V
DVDDS1
DVDD
1FF
PVDD
1FF
1.8V TO 3.6V
1FF
AVDD
1FF
SPKLVDD
1FF
SPKRVDD
1FF
DVDDS2
10kI
TO MICROCONTROLLER
BCLKS2
IRQ
10MHz TO 60MHz
CLOCK INPUT
LRCLKS2
MCLK
BCLKS1
DIGITAL AUDIO
PORT 1
I2C CONTROL
DATA
DIGITAL
MIC 1
DIGITAL
MIC 2
PORT
SDINS2
LRCLKS1
SDOUTS2
SDINS1
JACKSNS
SDOUTS1
RECP/RXINP
SDA
RECN/RXINN
SCL
DATA
MIC1N/DIGMICCLK
2.2kI
8I
MAX98088
SPKRP
8I
SPKRN
MICBIAS
1FF
HPR
MIC2P
HEADSET
MICROPHONE
32I
SPKLN
CLOCK
JACKSNS
JACKSNS
SPKLP
MIC1P/DIGMICDATA
CLOCK
DIGITAL
AUDIO
PORT 2
HPL
1FF
MIC2N
HPSNS
1FF
INA1/EXTMICP
LINE INPUT
REF
1FF
INA2/EXTMICN
1FF
REG
INB1
LINE INPUT
1FF
1FF
2.2FF
INB2
1FF
DGND AGND HPGND SPKRGND SPKLGND HPVDD
HPVSS
1FF
C1N
C1P
1FF
1FF
Figure 40. Typical Application Circuit Using the Digital Microphone Input and Receiver Amplifier
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MAX98088
Stereo Audio Codec
with FlexSound Technology
Filterless Class D Operation
In RF applications, improvements to both layout and component selection decrease the IC’s susceptibility to RF
noise and prevent RF signals from being demodulated into
audible noise. Trace lengths should be kept below 1/4 of
the wavelength of the RF frequency of interest. Minimizing
the trace lengths prevents them from functioning as antennas and coupling RF signals into the IC. The wavelength
(l) in meters is given by: l = c/f where c = 3 x 108 m/s, and
f = the RF frequency of interest.
The IC does not require an output filter. The device relies
on the inherent inductance of the speaker coil and the
natural filtering of both the speaker and the human ear
to recover the audio component of the square-wave output. Eliminating the output filter results in a smaller, less
costly, more efficient solution.
Route audio signals on middle layers of the PCB to allow
ground planes above and below to shield them from RF
interference. Ideally, the top and bottom layers of the
PCB should primarily be ground planes to create effective shielding.
Traditional Class D amplifiers require an output filter to
recover the audio signal from the amplifier’s output. The
filters add cost, increase the solution size of the amplifier,
and can decrease efficiency and THD+N performance.
The traditional PWM scheme uses large differential output
swings (2 x VDD peak to peak) and causes large ripple
currents. Any parasitic resistance in the filter components
results in a loss of power, lowering the efficiency.
Because the frequency of the IC’s output is well beyond
the bandwidth of most speakers, voice coil movement
due to the square-wave frequency is very small. Although
this movement is small, a speaker not designed to handle
the additional power can be damaged. For optimum
results, use a speaker with a series inductance > 10FH.
Typical 8I speakers exhibit series inductances in the
20FH to 100FH range.
RF Susceptibility
GSM radios transmit using time-division multiple access
(TDMA) with 217Hz intervals. The result is an RF signal
with strong amplitude modulation at 217Hz and its harmonics that is easily demodulated by audio amplifiers.
The IC is designed specifically to reject RF signals; however, PCB layout has a large impact on the susceptibility
of the end product.
Additional RF immunity can also be obtained by relying on the self-resonant frequency of capacitors as it
exhibits a frequency response similar to a notch filter.
Depending on the manufacturer, 10pF to 20pF capacitors typically exhibit self resonance at the RF frequencies
of interest. These capacitors, when placed at the input
pins, can effectively shunt the RF noise to ground. For
these capacitors to be effective, they must have a lowimpedance, low-inductance path to the ground plane.
Avoid using microvias to connect to the ground plane
whenever possible as these vias do not conduct well at
RF frequencies.
Startup/Shutdown Sequencing
To ensure proper device initialization and minimal clickand-pop, program the IC’s SHDN = 1 after configuring all
registers. Table 37 lists an example startup sequence for
the device. To shut down the IC, simply set SHDN = 0.
Table 37. Example Startup Sequence
SEQUENCE
DESCRIPTION
REGISTERS
1
Ensure SHDN = 0
0x51
2
Configure clocks
0x10 to 0x13, 0x19 to 0x1B
3
Configure digital audio interface
0x14 to 0x17, 0x1C to 0x1F
4
Configure digital signal processing
0x18, 0x20, 0x3F to 0x46
5
Load coefficients
0x52 to 0xC9
6
Configure mixers
0x22 to 0x2D
7
Configure gain and volume controls
0x2E to 0x3E
8
Configure miscellaneous functions
0x47 to 0x4B
9
Enable desired functions
0x4C, 0x50
10
Set SHDN = 1
0x51
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Stereo Audio Codec
with FlexSound Technology
Many configuration options in the ICs can be made
while the devices are operating, however, some registers should only be adjusted when the corresponding
audio path is disabled. Table 38 lists the registers that
are sensitive during operation. Either disable the corresponding audio path or set SHDN = 0 while changing
these registers.
Component Selection
Optional Ferrite Bead Filter
In applications where speaker leads exceed 20mm,
additional EMI suppression can be achieved by using a
filter constructed from a ferrite bead and a capacitor to
ground (Figure 41). Use a ferrite bead with low DC resistance, high-frequency (> 600MHz) impedance between
100I and 600I, and rated for at least 1A. The capacitor
value varies based on the ferrite bead chosen and the
actual speaker lead length. Select a capacitor less than
1nF based on EMI performance.
Input Capacitor
An input capacitor, CIN, in conjunction with the input
impedance of the IC line inputs forms a highpass filter
that removes the DC bias from an incoming analog
signal. The AC coupling capacitor allows the amplifier
to automatically bias the signal to an optimum DC level.
Assuming zero-source impedance, the -3dB point of the
highpass filter is given by:
1
f-3dB =
2πRINCIN
Choose CIN so that f-3dB is well below the lowest frequency of interest. For best audio quality use capacitors
whose dielectrics have low-voltage coefficients, such as
tantalum or aluminum electrolytic. Capacitors with highvoltage coefficients, such as ceramics, may result in
increased distortion at low frequencies.
Charge-Pump Capacitor Selection
Use capacitors with an ESR less than 100mI for optimum
performance. Low-ESR ceramic capacitors minimize the
output resistance of the charge pump. Most surfacemount ceramic capacitors satisfy the ESR requirement.
For best performance over the extended temperature
range, select capacitors with an X7R dielectric.
Table 38. Registers That Are Sensitive to Changes During Operation
REGISTER
DESCRIPTION
0x10 to 0x13, 0x19 to 0x1B
Clock Control Registers
0x14 to 0x17, 0x1C to 0x1F
Digital Audio Interface Configuration
0x18, 0x20
Digital Passband Filters
0x25 to 0x2D
Analog Mixers
0x52 to 0xC9
Digital Signal Processing Coefficients
SPK_P
MAX98088
SPK_N
Figure 41. Optional Class D Ferrite Bead Filter
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MAX98088
Stereo Audio Codec
with FlexSound Technology
Charge-Pump Flying Capacitor
The value of the flying capacitor (connected between
C1N and C1P) affects the output resistance of the charge
pump. A value that is too small degrades the device’s
ability to provide sufficient current drive, which leads to a
loss of output voltage. Increasing the value of the flying
capacitor reduces the charge-pump output resistance to
an extent. Above 1FF, the on-resistance of the internal
switches and the ESR of external charge- pump capacitors dominate.
Charge-Pump Holding Capacitor
The holding capacitor (bypassing HPVSS) value and ESR
directly affect the ripple at HPVSS. Increasing the capacitor’s value reduces output ripple. Likewise, decreasing
the ESR reduces both ripple and output resistance.
Lower capacitance values can be used in systems with
low maximum output power levels. See the Output Power
vs. Load Resistance graph in the Typical Operating
Characteristics section for more information
Unused Pins
Table 39 shows how to connect the IC’s pins when
unused.
Table 39. Unused Pins
NAME
CONNECTION
NAME
CONNECTION
SPKRP
Unconnected
INB1
Unconnected
SPKRVDD
Always connect
INA2/MICEXTN
Unconnected
SPKLVDD
Always connect
LRCLKS2
Unconnected
SPKLP
Unconnected
MCLK
Always connect
RECN/RXINN
Unconnected
SDINS2
AGND
HPVDD
Unconnected
Unconnected
C1P
Unconnected
IRQ
MIC1P/DIGMICDATA
HPGND
AGND
INA1/MICEXTP
Unconnected
Always connect
Unconnected
SPKRN
Unconnected
DGND
SPKRGND
Always connect
BCLKS2
Unconnected
SPKLGND
Always connect
SDA
Always connect
SPKLN
Unconnected
SCL
Always connect
RECP/RXINP
Unconnected
REG
Always connect
C1N
Unconnected
REF
Always connect
HPL
Unconnected
MIC1N/DIGMICCLK
Unconnected
HPVSS
Unconnected
MIC2P
Unconnected
SDINS1
AGND
SDOUTS2
Unconnected
LRCLKS1
Unconnected
DVDDS2
DVDD
HPSNS
AGND
DVDD
Always connect
INB2
Unconnected
AVDD
Always connect
HPR
Unconnected
PVDD
Always connect
DVDDS1
DVDD
AGND
Always connect
SDOUTS1
Unconnected
MICBIAS
Unconnected
BCLKS1
Unconnected
MIC2N
Unconnected
JACKSNS
Unconnected
��������������������������������������������������������������� Maxim Integrated Products 119
MAX98088
Stereo Audio Codec
with FlexSound Technology
Recommended PCB Routing
The IC uses a 63-bump WLP package. Figure 42 provides
an example of how to connect to all active bumps using
3 layers of the PCB. To ensure uninterrupted ground
returns, use layer 2 as a connecting layer between layer
1 and layer 2 and flood the remaining area with ground.
Supply Bypassing, Layout, and Grounding
Proper layout and grounding are essential for optimum
performance. When designing a PCB for the ICs, partition the circuitry so that the analog sections of the IC are
separated from the digital sections. This ensures that the
analog audio traces are not routed near digital traces.
Use a large continuous ground plane on a dedicated
layer of the PCB to minimize loop areas. Connect AGND,
DGND, HPGND, SPKLGND, and SPKRGND directly to
the ground plane using the shortest trace length possible.
Proper grounding improves audio performance, minimizes
crosstalk between channels, and prevents any digital
noise from coupling into the analog audio signals.
Ground the bypass capacitors on MICBIAS, REG, and
REF directly to the ground plane with minimum trace
length. Also be sure to minimize the path length to
AGND. Bypass AVDD directly to AGND.
LAYER 1
LAYER 2
LAYER 3
Figure 42. Suggested Routing for the MAX98088
Connect all digital I/O termination to the ground plane
with minimum path length to DGND. Bypass DVDD,
DVDDS1, and DVDDS2 directly to DGND.
Place the capacitor between C1P and C1N as close as
possible to the ICs to minimize trace length from C1P to
C1N. Inductance and resistance added between C1P
and C1N reduce the output power of the headphone
amplifier. Bypass HPVDD and HPVSS with a capacitor located close to HPVSS with a short trace length to
HPGND. Close decoupling of HPVSS minimizes supply
ripple and maximizes output power from the headphone
amplifier.
HPSNS senses ground noise on the headphone jack and
adds the same noise to the output audio signal, thereby
making the output (headphone output minus ground)
noise free. Connect HPSNS to the headphone jack shield
to ensure accurate pickup of headphone ground noise.
Bypass SPKLVDD and SPKRVDD to SPKLGND and
SPKRGND, respectively, with as little trace length as
possible. Connect SPKLP, SPKLN, SPKRP, and SPKRN
to the stereo speakers using the shortest traces possible. Reducing trace length minimizes radiated EMI.
Route SPKLP/SPKLN and SPKRP/SPKRN as differential
pairs on the PCB to minimize loop area, thereby the
inductance of the circuit. If filter components are used
on the speaker outputs, be sure to locate them as close
as possible to the IC to ensure maximum effectiveness.
Minimize the trace length from any ground-connected
passive components to SPKLGND and SPKRGND to
further minimize radiated EMI.
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MAX98088
Stereo Audio Codec
with FlexSound Technology
Route microphone signals from the microphone to the ICs
as a differential pair, ensuring that the positive and negative signals follow the same path as closely as possible
with equal trace length. When using single-ended microphones or other single-ended audio sources, ground the
negative microphone input as close as possible to the
audio source and then treat the positive and negative
traces as differential pairs.
0.24mm
An evaluation kit (EV kit) is available to provide an example layout for the IC. The EV kit allows quick setup of the
IC and includes easy-to-use software allowing all internal
registers to be controlled.
WLP Applications Information
For the latest application details on WLP construction,
dimensions, tape carrier information, PCB techniques,
bump-pad layout, and recommended reflow temperature
profile, as well as the latest information on reliability testing results, refer to the Application Note 1891: WaferLevel Packaging (WLP) and Its Applications. Figure 43
shows the dimensions of the WLP balls used on the
MAX98088.
0.21mm
Figure 43. WLP Ball Dimensions
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX98088EWY+
-40NC to +85NC
63 WLP
+Denotes lead(Pb)-free/RoHS-compliant package.
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with FlexSound Technology
Package Information
For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or
“-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains
to the package regardless of RoHS status.
PACKAGE TYPE
PACKAGE CODE
OUTLINE NO.
LAND PATTERN NO.
63 WLP
W633A3+1
21-0462
Refer to Application Note 1891
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Stereo Audio Codec
with FlexSound Technology
Revision History
REVISION
NUMBER
REVISION
DATE
0
6/10
1
6/11
DESCRIPTION
Initial release
PAGES
CHANGED
—
Made various updates, replaced TOCs 56 and 68
1, 5–27, 29,
30, 33, 35, 37,
39, 41, 43,
46, 54, 55, 56,
63–67, 69, 70,
70, 74, 75, 77,
80, 81, 83–86,
90, 94–99, 101,
103, 104, 105,
107, 109, 110,
111, 113, 114,
119, 120
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical
Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2011
Maxim Integrated Products 123
Maxim is a registered trademark of Maxim Integrated Products, Inc.
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