LM4889 1 Watt Audio Power Amplifier FEATURES DESCRIPTION

LM4889 1 Watt Audio Power Amplifier FEATURES DESCRIPTION
LM4889
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LM4889
1 Watt Audio Power Amplifier
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FEATURES
DESCRIPTION
•
The LM4889 is an audio power amplifier primarily
designed for demanding applications in mobile
phones and other portable communication device
applications. It is capable of delivering 1 watt of
continuous average power to an 8Ω BTL load with
less than 2% distortion (THD+N) from a 5VDC power
supply.
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23
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•
•
•
•
•
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Available in Space-Saving VSSOP, SOIC,
WSON, and DSBGA Packages
Ultra Low Current Shutdown Mode (3.3 to 2.6V
- 0.01µA)
Can Drive Capacitive Loads up to 500 pF
Improved Pop & Click Circuitry Eliminates
Noises During Turn-On and Turn-Off
Transitions
2.2 - 5.5V Operation
No Output Coupling Capacitors, Snubber
Networks or Bootstrap Capacitors Required
Unity-Gain Stable
External Gain Configuration Capability
APPLICATIONS
•
•
•
Mobile Phones
PDAs
Portable Electronic Devices
KEY SPECIFICATIONS
•
•
•
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Improved PSRR at 217Hz, 5 - 3.3V 75dB
Power Output at 5.0V & 2% THD 1.0W(typ.)
Power Output at 3.3V & 1% THD 400mW(typ.)
Shutdown Current at 3.3 & 2.6V 0.01µA(typ.)
Boomer™ audio power amplifiers were designed
specifically to provide high quality output power with a
minimal amount of external components. The
LM4889 does not require output coupling capacitors
or bootstrap capacitors, and therefore is ideally suited
for mobile phone and other low voltage applications
where minimal power consumption is a primary
requirement.
The LM4889 features a low-power consumption
shutdown mode, which is achieved by driving the
shutdown pin with a logic low. Additionally, the
LM4889 features an internal thermal shutdown
protection mechanism.
The LM4889 contains advanced pop & click circuitry
to eliminate noise which would otherwise occur during
turn-on and turn-off transitions.
The LM4889 is unity-gain stable and can be
configured by external gain-setting resistors.
1
2
3
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Boomer is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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LM4889
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Typical Application
Figure 1. Typical Audio Amplifier Application Circuit
Connection Diagram
Figure 2. Small Outline (SOIC) Package - Top View
See Package Number D
Figure 3. Mini Small Outline (VSSOP) Package –
Top View
See Package Number DGK
Figure 4. 8-Bump DSBGA - Top View
See Package Number YZR0008
Figure 5. WSON Package - Top View
See Package Number NGZ
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
2
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Absolute Maximum Ratings (1) (2)
Supply Voltage
6.0V
−65°C to +150°C
Storage Temperature
−0.3V to VDD +0.3V
Input Voltage
Power Dissipation (3)
Internally Limited
(4)
2000V
ESD Susceptibility
ESD Susceptibility (5)
200V
Junction Temperature
150°C
Thermal Resistance
θJC (SOIC)
35°C/W
θJA (SOIC)
150°C/W
θJA (8 Bump DSBGA) (6)
210°C/W
θJC (VSSOP)
56°C/W
θJA (VSSOP)
190°C/W
θJA (WSON)
220°C/W
Soldering Information
(1)
(2)
(3)
(4)
(5)
(6)
See the AN-1112 Application Report.
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not ensured for parameters where no limit is given, however, the typical value is a good indication
of device performance.
If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications.
The maximum power dissipation must be derated at elevated temperatures and is dictated by TJMAX, θJA, and the ambient temperature
TA. The maximum allowable power dissipation is PDMAX = (TJMAX–TA)/θJA or the number given in Absolute Maximum Ratings, whichever
is lower. For the LM4889, see power derating currents for additional information.
Human body model, 100 pF discharged through a 1.5 kΩ resistor.
Machine Model, 220 pF–240 pF discharged through all pins.
All bumps have the same thermal resistance and contribute equally when used to lower thermal resistance. The LM4889ITL demo board
(views featured in the Application Information section) has two inner layers, one for VDD and one for GND. The planes each measure
600mils x 600mils (15.24mm x 15.24mm) and aid in spreading heat due to power dissipation within the IC.
Operating Ratings
Temperature Range TMIN ≤ TA ≤ TMAX
−40°C ≤ TA ≤ 85°C
2.2V ≤ VDD ≤ 5.5V
Supply Voltage
Electrical Characteristics VDD = 5V (1) (2)
The following specifications apply for VDD = 5V, AV = 2, and 8Ω load unless otherwise specified. Limits apply for TA = 25°C.
Symbol
Parameter
Conditions
VIN = 0V, Io = 0A, no Load
IDD
Quiescent Power Supply Current
ISD
Shutdown Current
VSDIH
Shutdown Voltage Input High
VSDIL
Shutdown Voltage Input Low
Po
Output Power
THD = 2% (max); f = 1 kHz
THD+N
Total Harmonic Distortion+Noise
Po = 0.4 Wrms; f = 1kHz
(1)
(2)
(3)
(4)
(5)
(6)
VIN = 0V, Io = 0A, with BTL Load
Vshutdown = GND (6)
LM4889
Limit (4) (5)
Units
(Limits)
4
8
mA (max)
5
8
mA (max)
0.1
2
µA (max)
1.2
V (min)
0.4
V (max)
Typical (3)
1
W
0.1
%
All voltages are measured with respect to the ground pin, unless otherwise specified.
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not ensured for parameters where no limit is given, however, the typical value is a good indication
of device performance.
Typicals are measured at 25°C and represent the parametric norm.
Limits are specified to TI's AOQL (Average Outgoing Quality Level).
Datasheet min/max specification limits are specified by design, test or statistical analysis.
For DSBGA only, shutdown current is measured in a Normal Room Environment. Exposure to direct sunlight will increase ISD by a
maximum of 2µA.
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Electrical Characteristics VDD = 5V(1)(2) (continued)
The following specifications apply for VDD = 5V, AV = 2, and 8Ω load unless otherwise specified. Limits apply for TA = 25°C.
Symbol
PSRR
Parameter
Power Supply Rejection Ratio
Conditions
LM4889
Typical
Vripple = 200mV sine p-p
fripple = 217Hz
fripple = 1kHz
62
66
Vripple = 200mV sine p-p
Input Floating
75
(3)
Limit (4) (5)
Units
(Limits)
dB
dB
68
dB
Electrical Characteristics VDD = 3.3V (1) (2)
The following specifications apply for VDD = 3.3V, AV = 2, and 8Ω load unless otherwise specified. Limits apply for TA = 25°C.
Symbol
IDD
Parameter
Quiescent Power Supply Current
Conditions
LM4889
Typical
(3)
Limit (4) (5)
Units
(Limits)
VIN = 0V, Io = 0A, no Load
3.5
7
mA (max)
VIN = 0V, Io = 0A, with BTL Load
4.5
7
mA (max)
2
µA (max)
ISD
Shutdown Current
VSDIH
Shutdown Voltage Input High
1.2
V (min)
VSDIL
Shutdown Voltage Input Low
0.4
V (max)
Po
Output Power
THD = 1% (max); f = 1kHz
0.4
W
THD+N
Total Harmonic Distortion+Noise
Po = 0.25Wrms; f = 1kHz
0.1
%
Power Supply Rejection Ratio
Vripple = 200mV sine p-p
fripple = 217Hz
fripple =1kHz
60
62
dB
dB
PSRR
(1)
(2)
(3)
(4)
(5)
(6)
Vshutdown = GND
(6)
0.01
All voltages are measured with respect to the ground pin, unless otherwise specified.
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not ensured for parameters where no limit is given, however, the typical value is a good indication
of device performance.
Typicals are measured at 25°C and represent the parametric norm.
Limits are specified to TI's AOQL (Average Outgoing Quality Level).
Datasheet min/max specification limits are specified by design, test or statistical analysis.
For DSBGA only, shutdown current is measured in a Normal Room Environment. Exposure to direct sunlight will increase ISD by a
maximum of 2µA.
Electrical Characteristics VDD = 2.6V (1) (2)
The following specifications apply for VDD = 2.6V, AV = 2, and 8Ω load unless otherwise specified. Limits apply for TA = 25°C.
Symbol
IDD
Parameter
Quiescent Power Supply Current
LM4889
Typical (3)
Limit (4) (5)
Units
(Limits)
VIN = 0V, Io = 0A, no Load
2.6
6
mA (max)
VIN = 0V, Io = 0A, with BTL Load
3.0
6
mA (max)
2
µA (max)
Conditions
ISD
Shutdown Current
Vshutdown = GND (6)
0.01
P0
Output Power ( 8Ω )
Output Power ( 4Ω )
THD = 1% (max); f = 1 kHz
THD = 1% (max); f = 1 kHz
0.2
0.22
W
W
THD+N
Total Harmonic Distortion+Noise
Po = 0.1Wrms; f = 1kHz
0.08
%
(1)
(2)
(3)
(4)
(5)
(6)
4
All voltages are measured with respect to the ground pin, unless otherwise specified.
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not ensured for parameters where no limit is given, however, the typical value is a good indication
of device performance.
Typicals are measured at 25°C and represent the parametric norm.
Limits are specified to TI's AOQL (Average Outgoing Quality Level).
Datasheet min/max specification limits are specified by design, test or statistical analysis.
For DSBGA only, shutdown current is measured in a Normal Room Environment. Exposure to direct sunlight will increase ISD by a
maximum of 2µA.
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Electrical Characteristics VDD = 2.6V(1)(2) (continued)
The following specifications apply for VDD = 2.6V, AV = 2, and 8Ω load unless otherwise specified. Limits apply for TA = 25°C.
Symbol
PSRR
Parameter
Conditions
LM4889
Typical
Vripple = 200mV sine p-p
fripple = 217Hz
fripple = 1kHz
Power Supply Rejection Ratio
(3)
Limit (4) (5)
44
44
Units
(Limits)
dB
dB
External Components Description
(Figure 1)
Components
Functional Description
1.
Ri
Inverting input resistance which sets the closed-loop gain in conjunction with Rf. This resistor also forms a high pass
filter with Ci at fC= 1/(2π RiCi).
2.
Ci
Input coupling capacitor which blocks the DC voltage at the amplifiers input terminals. Also creates a highpass filter with
Ri at fc = 1/(2π RiCi). Refer to the section, PROPER SELECTION OF EXTERNAL COMPONENTS, for an explanation
of how to determine the value of Ci.
3.
Rf
Feedback resistance which sets the closed-loop gain in conjunction with Ri. AVD = 2*(Rf/Ri).
4.
CS
Supply bypass capacitor which provides power supply filtering. Refer to the POWER SUPPLY BYPASSING section for
information concerning proper placement and selection of the supply bypass capacitor.
5.
CB
Bypass pin capacitor which provides half-supply filtering. Refer to the section, PROPER SELECTION OF EXTERNAL
COMPONENTS, for information concerning proper placement and selection of CB.
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Typical Performance Characteristics
6
THD+N vs Frequency
at VDD = 5V, 8Ω RL, and PWR = 250mW
THD+N vs Frequency
at VDD = 3.3V, 8Ω RL, and PWR = 150mW
Figure 6.
Figure 7.
THD+N vs Frequency
at VDD = 2.6V, 8Ω RL, and PWR = 100mW
THD+N vs Frequency
at VDD = 2.6V, 4Ω RL, and PWR = 100mW
Figure 8.
Figure 9.
THD+N vs Power Out
at VDD = 5V, 8Ω RL, 1kHz
THD+N vs Power Out
at VDD = 3.3V, 8Ω RL, 1kHz
Figure 10.
Figure 11.
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Typical Performance Characteristics (continued)
THD+N vs Power Out
at VDD = 2.6V, 8Ω RL, 1kHz
THD+N vs Power Out
at VDD = 2.6V, 4Ω RL, 1kHz
Figure 12.
Figure 13.
Power Supply Rejection Ratio (PSRR) at VDD = 5V
Power Supply Rejection Ratio (PSRR) at VDD = 5V
Figure 14. Input terminated with 10Ω R
Figure 15. Input Floating
Power Supply Rejection Ratio (PSRR) at VDD = 2.6V
Power Supply Rejection Ratio (PSRR) at VDD = 3.3V
Figure 16. Input terminated with 10Ω R
Figure 17. Input terminated with 10Ω R
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Typical Performance Characteristics (continued)
8
Power Dissipation vs
Output Power
VDD = 3.3V
Power Dissipation vs
Output Power
VDD = 5V
Figure 18.
Figure 19.
Output Power vs
Load Resistance
Power Dissipation vs
Output Power
VDD = 2.6V
Figure 20.
Figure 21.
Supply Current vs
Shutdown Voltage
Clipping (Dropout) Voltage vs
Supply Voltage
Figure 22.
Figure 23.
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Typical Performance Characteristics (continued)
Open Loop Frequency Response
Frequency Response vs
Input Capacitor Size
Figure 24.
Figure 25.
Noise Floor
Power Derating Curves
(PDMAX = 670mW)
Figure 26.
Figure 27.
Power Derating Curves - 8 bump µSMD
(PDMAX = 670mW)
Power Derating Curves - 10 Pin LD pkg
(PDMAX = 670mW)
Figure 28.
Figure 29.
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Application Information
BRIDGE CONFIGURATION EXPLANATION
As shown in Figure 1, the LM4889 has two operational amplifiers internally, allowing for a few different amplifier
configurations. The first amplifier's gain is externally configurable, while the second amplifier is internally fixed in
a unity-gain, inverting configuration. The closed-loop gain of the first amplifier is set by selecting the ratio of Rf to
Ri while the second amplifier's gain is fixed by the two internal 20kΩ resistors. Figure 1 shows that the output of
amplifier one serves as the input to amplifier two which results in both amplifiers producing signals identical in
magnitude, but out of phase by 180°. Consequently, the differential gain for the IC is
AVD= 2 *(Rf/Ri)
(1)
By driving the load differentially through outputs Vo1 and Vo2, an amplifier configuration commonly referred to as
“bridged mode” is established. Bridged mode operation is different from the classical single-ended amplifier
configuration where one side of the load is connected to ground.
A bridge amplifier design has an advantage over the single-ended configuration, as it provides differential drive to
the load, thus doubling output swing for a specified supply voltage. Four times the output power is possible as
compared to a single-ended amplifier under the same conditions. This increase in attainable output power
assumes that the amplifier is not current limited or clipped. In order to choose an amplifier's closed-loop gain
without causing excessive clipping, please refer to the AUDIO POWER AMPLIFIER DESIGN section.
A bridge configuration, such as the one used in LM4889, also creates a second advantage over single-ended
amplifiers. Since the differential outputs, Vo1 and Vo2, are biased at half-supply, no net DC voltage exists across
the load. This eliminates the need for an output coupling capacitor which is required in a single supply, singleended amplifier configuration. Without an output coupling capacitor, the half-supply bias across the load would
result in both increased internal IC power dissipation and also possible loudspeaker damage.
POWER DISSIPATION
Power dissipation is a major concern when designing a successful amplifier, whether the amplifier is bridged or
single-ended. A direct consequence of the increased power delivered to the load by a bridge amplifier is an
increase in internal power dissipation. Since the LM4889 has two operational amplifiers in one package, the
maximum internal power dissipation is 4 times that of a single-ended amplifier. The maximum power dissipation
for a given application can be derived from the power dissipation graphs or from Equation 2.
PDMAX = 4*(VDD)2/(2π2RL)
(2)
It is critical that the maximum junction temperature TJMAX of 150°C is not exceeded. TJMAX can be determined
from the power derating curves by using PDMAX and the PC board foil area. By adding additional copper foil, the
thermal resistance of the application can be reduced from a free air value of 150°C/W, resulting in higher PDMAX.
Additional copper foil can be added to any of the leads connected to the LM4889. It is especially effective when
connected to VDD, GND, and the output pins. Refer to the application information on the LM4889 reference design
board for an example of good heat sinking. If TJMAX still exceeds 150°C, then additional changes must be made.
These changes can include reduced supply voltage, higher load impedance, or reduced ambient temperature.
Internal power dissipation is a function of output power. Refer to the Typical Performance Characteristics curves
for power dissipation information for different output powers and output loading.
POWER SUPPLY BYPASSING
As with any amplifier, proper supply bypassing is critical for low noise performance and high power supply
rejection. The capacitor location on both the bypass and power supply pins should be as close to the device as
possible. Typical applications employ a 5V regulator with 10 µF tantalum or electrolytic capacitor and a ceramic
bypass capacitor which aid in supply stability. This does not eliminate the need for bypassing the supply nodes of
the LM4889. The selection of a bypass capacitor, especially CB, is dependent upon PSRR requirements, click
and pop performance (as explained in the section, PROPER SELECTION OF EXTERNAL COMPONENTS),
system cost, and size constraints.
10
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SHUTDOWN FUNCTION
In order to reduce power consumption while not in use, the LM4889 contains a shutdown pin to externally turn off
the amplifier's bias circuitry. This shutdown feature turns the amplifier off when a logic low is placed on the
shutdown pin. By switching the shutdown pin to ground, the LM4889 supply current draw will be minimized in idle
mode. While the device will be disabled with shutdown pin voltages less than 0.5VDC, the idle current may be
greater than the typical value of 0.1µA. (Idle current is measured with the shutdown pin grounded).
In many applications, a microcontroller or microprocessor output is used to control the shutdown circuitry to
provide a quick, smooth transition into shutdown. Another solution is to use a single-pole, single-throw switch in
conjunction with an external pull-up resistor. When the switch is closed, the shutdown pin is connected to ground
and disables the amplifier. If the switch is open, then the external pull-up resistor will enable the LM4889. This
scheme ensures that the shutdown pin will not float thus preventing unwanted state changes.
PROPER SELECTION OF EXTERNAL COMPONENTS
Proper selection of external components in applications using integrated power amplifiers is critical to optimize
device and system performance. While the LM4889 is tolerant of external component combinations,
consideration to component values must be used to maximize overall system quality.
The LM4889 is unity-gain stable which gives the designer maximum system flexibility. The LM4889 should be
used in low gain configurations to minimize THD+N values, and maximize the signal to noise ratio. Low gain
configurations require large input signals to obtain a given output power. Input signals equal to or greater than 1
Vrms are available from sources such as audio codecs. Please refer to the section, AUDIO POWER AMPLIFIER
DESIGN, for a more complete explanation of proper gain selection.
Besides gain, one of the major considerations is the closed-loop bandwidth of the amplifier. To a large extent, the
bandwidth is dictated by the choice of external components shown in Figure 1. The input coupling capacitor, Ci,
forms a first order high pass filter which limits low frequency response. This value should be chosen based on
needed frequency response for a few reasons.
SELECTION OF INPUT CAPACITOR SIZE
Large input capacitors are both expensive and space hungry for portable designs. Clearly, a certain sized
capacitor is needed to couple in low frequencies without severe attenuation. But in many cases the speakers
used in portable systems, whether internal or external, have little ability to reproduce signals below 100 Hz to
150 Hz. Thus, using a large input capacitor may not increase actual system performance.
In addition to system cost and size, click and pop performance is effected by the size of the input coupling
capacitor, Ci. A larger input coupling capacitor requires more charge to reach its quiescent DC voltage (nominally
1/2 VDD). This charge comes from the output via the feedback and is apt to create pops upon device enable.
Thus, by minimizing the capacitor size based on necessary low frequency response, turn-on pops can be
minimized.
Besides minimizing the input capacitor size, careful consideration should be paid to the bypass capacitor value.
Bypass capacitor, CB, is the most critical component to minimize turn-on pops since it determines how fast the
LM4889 turns on. The slower the LM4889's outputs ramp to their quiescent DC voltage (nominally 1/2 VDD), the
smaller the turn-on pop. Choosing CB equal to 1.0 µF along with a small value of Ci (in the range of 0.1 µF to
0.39 µF), should produce a virtually clickless and popless shutdown function. While the device will function
properly, (no oscillations or motorboating), with CB equal to 0.1 µF, the device will be much more susceptible to
turn-on clicks and pops. Thus, a value of CB equal to 1.0 µF is recommended in all but the most cost sensitive
designs.
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AUDIO POWER AMPLIFIER DESIGN
A 1W/8Ω Audio Amplifier
• Given:
– Power Output: 1 Wrms
– Load Impedance: 8Ω
– Input Level: 1 Vrms
– Input Impedance: 20 kΩ
– Bandwidth: 100 Hz–20 kHz ± 0.25 dB
A designer must first determine the minimum supply rail to obtain the specified output power. By extrapolating
from the Output Power vs Supply Voltage graphs in the Typical Performance Characteristics section, the supply
rail can be easily found. A second way to determine the minimum supply rail is to calculate the required Vopeak
using Equation 3 and add the output voltage. Using this method, the minimum supply voltage would be (Vopeak +
(VODTOP + VODBOT)), where VODBOT and VODTOP are extrapolated from the Dropout Voltage vs Supply Voltage curve in
the Typical Performance Characteristics section.
(3)
5V is a standard voltage in most applications, it is chosen for the supply rail. Extra supply voltage creates
headroom that allows the LM4889 to reproduce peaks in excess of 1W without producing audible distortion. At
this time, the designer must make sure that the power supply choice along with the output impedance does not
violate the conditions explained in the POWER DISSIPATION section.
Once the power dissipation equations have been addressed, the required differential gain can be determined
from Equation 4.
(4)
(5)
Rf/Ri = AVD/2
From Equation 3, the minimum AVD is 2.83; use AVD = 3.
Since the desired input impedance was 20 kΩ, and with a AVD impedance of 2, a ratio of 1.5:1 of Rf to Ri results
in an allocation of Ri = 20 kΩ and Rf = 30 kΩ. The final design step is to address the bandwidth requirements
which must be stated as a pair of −3 dB frequency points. Five times away from a −3 dB point is 0.17 dB down
from passband response which is better than the required ±0.25 dB specified.
fL = 100 Hz/5 = 20 Hz
fH = 20 kHz * 5 = 100 kHz
(6)
(7)
As stated in the External Components Description section, Ri in conjunction with Ci create a highpass filter.
Ci ≥ 1/(2π*20 kΩ*20 Hz) = 0.397 µF; use 0.39 µF
(8)
The high frequency pole is determined by the product of the desired frequency pole, fH, and the differential gain,
AVD. With a AVD = 3 and fH = 100 kHz, the resulting GBWP = 300kHz which is much smaller than the LM4889
GBWP of 2.5MHz. This calculation shows that if a designer has a need to design an amplifier with a higher
differential gain, the LM4889 can still be used without running into bandwidth limitations.
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Figure 30. Higher Gain Audio Amplifier
The LM4889 is unity-gain stable and requires no external components besides gain-setting resistors, an input
coupling capacitor, and proper supply bypassing in the typical application. However, if a closed-loop differential
gain of greater than 10 is required, a feedback capacitor (C4) may be needed as shown in Figure 30 to
bandwidth limit the amplifier. This feedback capacitor creates a low pass filter that eliminates possible high
frequency oscillations. Care should be taken when calculating the -3dB frequency in that an incorrect
combination of R3 and C4 will cause rolloff before 20kHz. A typical combination of feedback resistor and
capacitor that will not produce audio band high frequency rolloff is R3 = 20kΩ and C4 = 25pf. These components
result in a -3dB point of approximately 320kHz.
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LM4889
SNAS157H – APRIL 2002 – REVISED MAY 2013
www.ti.com
Figure 31. Differential Amplifier Configuration for LM4889
Figure 32. Reference Design Board and Layout - DSBGA
14
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LM4889
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SNAS157H – APRIL 2002 – REVISED MAY 2013
LM4889 DSBGA DEMO BOARD ARTWORK
Composite View
Silk Screen
Top Layer
Bottom Layer
Inner Layer Ground
Inner Layer VDD
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Product Folder Links: LM4889
15
LM4889
SNAS157H – APRIL 2002 – REVISED MAY 2013
www.ti.com
REFERENCE DESIGN BOARD AND PCB LAYOUT GUIDELINES - VSSOP & SOIC BOARDS
Figure 33. Reference Design Board
LM4889 SOIC DEMO BOARD ARTWORK
Figure 34. Silk Screen
16
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LM4889
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SNAS157H – APRIL 2002 – REVISED MAY 2013
Figure 35. Top Layer
Figure 36. Bottom Layer
LM4889 VSSOP DEMO BOARD ARTWORK
Figure 37. Silk Screen
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17
LM4889
SNAS157H – APRIL 2002 – REVISED MAY 2013
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Figure 38. Top Layer
Figure 39. Bottom Layer
18
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LM4889
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SNAS157H – APRIL 2002 – REVISED MAY 2013
REVISION HISTORY
Changes from Revision G (May 2013) to Revision H
•
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 18
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19
PACKAGE OPTION ADDENDUM
www.ti.com
12-Jul-2014
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
LM4889MA/NOPB
ACTIVE
SOIC
D
8
95
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
LM48
89MA
LM4889MAX/NOPB
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
LM48
89MA
LM4889MM/NOPB
ACTIVE
VSSOP
DGK
8
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
GA2
LM4889MMX/NOPB
ACTIVE
VSSOP
DGK
8
3500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
GA2
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
12-Jul-2014
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
12-Aug-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
LM4889MAX/NOPB
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
LM4889MM/NOPB
VSSOP
DGK
8
1000
178.0
12.4
5.3
3.4
1.4
8.0
12.0
Q1
LM4889MMX/NOPB
VSSOP
DGK
8
3500
330.0
12.4
5.3
3.4
1.4
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
12-Aug-2013
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LM4889MAX/NOPB
SOIC
D
8
2500
367.0
367.0
35.0
LM4889MM/NOPB
VSSOP
DGK
8
1000
210.0
185.0
35.0
LM4889MMX/NOPB
VSSOP
DGK
8
3500
367.0
367.0
35.0
Pack Materials-Page 2
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