LM4915 Pseudo-Differential Mono Headphone Amplifier with Fixed

LM4915 Pseudo-Differential Mono Headphone Amplifier with Fixed
LM4915
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LM4915
SNAS176A – MAY 2003 – REVISED MAY 2013
Pseudo-Differential Mono Headphone Amplifier
with Fixed 6dB Gain
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FEATURES
DESCRIPTION
•
•
•
•
•
•
The LM4915 is a pseudo-differential audio power
amplifier
primarily
designed
for
demanding
applications in mobile phones and other portable
audio device applications with mono headphones. It
is capable of delivering 90 miliwatts of continuous
average power to a 32Ω BTL load with less than 1%
distortion (THD+N) from a 3VDC power supply.
1
2
•
•
•
Pseudo-Differential Amplification
Internal Gain-Setting Resistors
Available in Space-Saving WQFN Package
Ultra Low Current Shutdown Mode
Can Drive Capacitive Loads up to 500pF
Improved Pop & Click Circuitry Virtually
Eliminates Noises During Turn-On and TurnOff Transitions
2.2 - 5.5V Operation
No Output Coupling Capacitors, Snubber
Networks, Bootstrap Capacitors or GainSetting Resistors Required
Ultra Low Noise
KEY SPECIFICATIONS
•
•
•
•
Improved PSRR at 217Hz and 1kHz: 75dB (Typ)
Power Output at 5.0V & 1% THD into 32Ω:
280mW (Typ)
Power Output at 3.0V & 1% THD into 32Ω:
90mW (Typ)
Output Noise, A-weighted: 20μV (Typ)
APPLICATIONS
•
•
•
Boomer audio power amplifiers were designed
specifically to provide high quality output power with a
minimal amount of external components. The
LM4915 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 LM4915 features a low-power consumption
shutdown mode. To facilitate this, Shutdown may be
enabled by driving the shutdown pin low. Additionally,
the LM4915 features an internal thermal shutdown
protection mechanism.
The LM4915 contains advanced pop & click circuitry
which virtually eliminates noises which would
otherwise occur during turn-on and turn-off
transitions.
The LM4915 has an internally fixed gain of 6dB.
Mobile Phones
PDAs
Portable Electronics Devices
1
2
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.
All 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.
Copyright © 2003–2013, Texas Instruments Incorporated
LM4915
SNAS176A – MAY 2003 – REVISED MAY 2013
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Typical Application
Figure 1. Typical Audio Amplifier Application Circuit
Connection Diagrams
Figure 2. WQFN Package – Top View
See Package Number NGP0008A
2
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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.
Absolute Maximum Ratings (1) (2)
Supply Voltage
6.0V
−65°C to +150°C
Storage Temperature
Input Voltage
Power Dissipation
-0.3V to VDD + 0.3V
(3)
ESD Susceptibility
Internally Limited
Human Body Model (4)
2000V
Machine Model (5)
200V
Junction Temperature
Thermal Resistance
(1)
(2)
(3)
(4)
(5)
150°C
θJC (WQFN)
57°C/W
θJA (WQFN)
140°C/W
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 Texas Instruments 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 LM4915, see power derating curves for more information.
Human body model, 100pF discharged through a 1.5kΩ resistor.
Machine Model, 220pF-240pF discharged through all pins.
Operating Ratings
Temperature Range (TMIN ≤ TA ≤ TMAX)
−40°C ≤ TA ≤ +85°C
2.2V ≤ VCC ≤ 5.5V
Supply Voltage (VDD)
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Electrical Characteristics VDD = 5V (1) (2) (3)
The following specifications apply for VDD = 5V, RL = 16Ω unless otherwise specified. Limits apply to TA = 25°C.
Symbol
Parameter
Conditions
LM4915
Typ
IDD
Quiescent Power Supply Current
VIN = 0V, IO = 0A
ISD
Shutdown Current
VSHUTDOWN = GND
VSDIH
Shutdown Voltage Input High
VSDIL
Shutdown Voltage Input Low
PO
Output Power
(4)
3.5
mA (max)
0.1
See (6)
µA(max)
1.8
V
0.4
V
THD = 1% (max); f = 1kHz
RL = 16
RL = 32
400
280
Output Noise Voltage
BW = 20Hz to 20kHz, A-weighted
20
PSRR
Power Supply Rejection Ratio
VRIPPLE = 200mV sine p-p
75
VOS
Output Offset Voltage
VIN = 0V
2
(3)
(4)
(5)
(6)
4
Units
(Limits)
2
VNO
(1)
(2)
Limit
(5)
375
250
mW
µV
dB
20
mV (max)
All voltages are measured with respect to the GND 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.
Datasheet min/max specifications are specified by design, test, or statistical analysis.
Typicals are measured at 25°C and represent the parametric norm.
Limits are specified to AOQL (Average Outgoing Quality Level).
See ISD distribution values shown in the ISD Distribution curves, VDD = 5V and V = 3V, (Figure 29 and Figure 30, respectively) shown in
the Typical Performance Characteristics section.
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Electrical Characteristics VDD = 3.0V (1) (2) (3)
The following specifications apply for VDD = 3.0V, RL = 16Ω unless otherwise specified. Limits apply to TA = 25°C.
Symbol
Parameter
Conditions
LM4915
Typ
(4)
Limit
Units
(Limits)
(5)
IDD
Quiescent Power Supply Current
VIN = 0V, IO = 0A
1.5
ISD
Shutdown Current
VSHUTDOWN = GND
0.1
VSDIH
Shutdown Voltage Input High
1.8
V
VSDIL
Shutdown Voltage Input Low
0.4
V
PO
Output Power
THD = 1% (max); f = 1kHz
RL = 16
RL = 32
125
90
2.5
See
(6)
100
80
mA (max)
µA(max)
mW (min)
VNO
Output Noise Voltage
BW = 20Hz to 20kHz, A-weighted
20
µV
PSRR
Power Supply Rejection Ratio
VRIPPLE = 200mV sine p-p
70
dB
VOS
Output Offset Voltage
VIN = 0V
2
(1)
(2)
(3)
(4)
(5)
(6)
20
mV (max)
All voltages are measured with respect to the GND 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.
Datasheet min/max specifications are specified by design, test, or statistical analysis.
Typicals are measured at 25°C and represent the parametric norm.
Limits are specified to AOQL (Average Outgoing Quality Level).
See ISD distribution values shown in the ISD Distribution curves, VDD = 5V and V = 3V, (Figure 29 and Figure 30, respectively) shown in
the Typical Performance Characteristics section.
External Components Description
(Figure 1)
Components
Functional Description
1.
CB
Bypass pin capacitor that provides half-supply filtering. Refer to the section Proper Selection of External
Components for information concerning proper placement and selection of CB.
2.
Ci
Input coupling capacitor which blocks the DC voltage at the amplifier's input terminals. Also creates a high-pass filter
with the internal input resistance Ri. For the LM4915, Ri = 20kΩ, thus creating a high-pass filter fc = 1/(2πRiCi). Refer to
the section Proper Selection of External Components for an explanation of how to determine the value of Ci.
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Typical Performance Characteristics
THD+N vs Frequency
VDD = 5V, RL = 32Ω
10
10
1
1
THD+N (%)
THD+N (%)
THD+N vs Frequency
VDD = 5V, RL = 16Ω
0.1
0.01
0.001
20
0.1
0.01
100
1k
0.001
20
10k 20k
100
FREQUENCY (Hz)
Figure 4.
THD+N vs Frequency
VDD = 3V, RL = 16Ω, PO = 100mW
THD+N vs Frequency
VDD = 3V, RL = 32Ω, PO = 80mW
10
10
1
1
0.1
0.01
0.001
20
0.1
0.01
100
1k
0.001
20
10k 20k
100
10k 20k
Figure 5.
Figure 6.
THD+N vs Frequency
VDD = 2.6V, RL = 16Ω, PO = 50mW
THD+N vs Frequency
VDD = 2.6V, RL = 32Ω, PO = 40mW
10
10
1
1
0.1
0.01
0.1
0.01
100
1k
10k 20k
0.001
20
FREQUENCY (Hz)
100
1k
10k 20k
FREQUENCY (Hz)
Figure 7.
6
1k
FREQUENCY (Hz)
THD+N (%)
THD+N (%)
FREQUENCY (Hz)
0.001
20
10k 20k
Figure 3.
THD+N (%)
THD+N (%)
FREQUENCY (Hz)
1k
Figure 8.
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Typical Performance Characteristics (continued)
THD+N vs Output Power
VDD = 5V, RL = 16Ω
THD+N vs Output Power
VDD = 5V, RL = 32Ω
10
10
1
1
20kHz
THD+N (%)
THD+N (%)
20kHz
1kHz
0.1
0.1
1kHz
20Hz
0.01
20Hz
0.01
0.001
0.001
0.01
0.1
0.001
0.001
1
0.01
OUTPUT POWER (W)
0.1
1
OUTPUT POWER (W)
Figure 9.
Figure 10.
THD+N vs Output Power
VDD = 3V, RL = 16Ω
THD+N vs Output Power
VDD = 3V, RL = 32Ω
10
10
20kHz
1
THD+N (%)
THD+N (%)
1
1kHz
0.1
20Hz
20kHz
1kHz
0.1
20Hz
0.01
0.01
0.001
0.001
0.1
0.01
0.5
0.001
0.001
OUTPUT POWER (W)
0.1
Figure 11.
Figure 12.
THD+N vs Output Power
VDD = 2.6V, RL = 16Ω
THD+N vs Output Power
VDD = 2.6V, RL = 32Ω
0.5
10
10
20kHz
1
THD+N (%)
1
THD+N (%)
0.01
OUTPUT POWER (W)
1kHz
0.1
0.1
20Hz
0.01
0.01
0.001
0.001
0.001
0.001
0.01
0.1
0.5
0.01
0.1
0.5
OUTPUT POWER (W)
OUTPUT POWER (W)
Figure 13.
Figure 14.
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Typical Performance Characteristics (continued)
PSRR vs Frequency
VDD = 5V, RL = 32Ω, PO = 250mW
Input 10Ω Terminated
0
0
-10
-10
-20
-20
-30
-30
PSRR (dB)
PSRR (dB)
PSRR vs Frequency
VDD = 5V, RL = 16Ω, PO = 375mW
Input 10Ω Terminated
-40
-50
-60
-40
-50
-60
-70
-70
-80
-80
-90
-90
-100
20
-100
20
100
1k
10k
100
100
Figure 16.
PSRR vs Frequency
VDD = 3V, RL = 16Ω
Input 10Ω Terminated
PSRR vs Frequency
VDD = 3V, RL = 32Ω
Input 10Ω Terminated
0
0
-10
-20
-20
-30
-30
-40
-50
-60
-40
-50
-60
-70
-70
-80
-80
-90
-90
100
1k
10k
-100
20
100
100
FREQUENCY (Hz)
1k
10k
100
FREQUENCY (Hz)
Figure 17.
Figure 18.
PSRR vs Frequency
VDD = 2.6V, RL = 16Ω
Input 10Ω Terminated
PSRR vs Frequency
VDD = 2.6V, RL = 32Ω
Input 10Ω Terminated
0
0
-10
-10
-20
-20
-30
-30
-40
PSRR (dB)
PSRR (dB)
100
FREQUENCY (Hz)
-10
-100
20
10k
Figure 15.
PSRR (dB)
PSRR (dB)
FREQUENCY (Hz)
1k
-50
-60
-40
-50
-60
-70
-70
-80
-80
-90
-100
20
-90
100
1k
10k
FREQUENCY (Hz)
100
-100
20
100
1k
10k
100
FREQUENCY (Hz)
Figure 19.
8
Figure 20.
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Typical Performance Characteristics (continued)
Output Power vs Load Resistance
VDD = 2.6V, RL = 32Ω
Output Power vs Supply Voltage
RL = 16Ω
1
600
900m
800m
OUTPUT POWER (W)
OUTPUT POWER (mW)
500
VDD = 5V, 10% THD+N
400
VDD = 5V, 1% THD+N
300
VDD = 3V, 10% THD+N
200
700m
600m
10% THD+N
500m
400m
300m
1% THD+N
200m
100
100m
VDD = 3V, 1% THD+N
0
2.2 2.5
0
0 16
32
48
64
80
96
112 128
LOAD RESISTANCE (:)
4
4.5
5
5.5
SUPPLY VOLTAGE (V)
Figure 22.
Output Power vs Supply Voltage
RL = 32Ω
Power Dissipation vs Output Power
VDD = 5V
1
350
POWER DISSIPATION (mW)
800m
OUTPUT POWER (W)
3.5
Figure 21.
900m
700m
600m
500m
400m
300m
10% THD+N
200m
300
RL = 16:
200
RL = 32:
100
1% THD+N
100m
0
2.2 2.5
0
3
3.5
4
4.5
5
5.5
100
0
SUPPLY VOLTAGE (V)
200
300
400 450
OUTPUT POWER (mW)
Figure 23.
Figure 24.
Power Dissipation vs Output Power
VDD = 3V
Frequency Response
vs Input Capacitor Size
10
140
8
120
6
RL = 16:
OUTPUT LEVEL (dB)
POWER DISSIPATION (mW)
3
100
80
60
RL = 32:
40
Ci = 0.47uF
4
Ci = 0.33uF
2
0
-2
Ci = 0.1uF
-4
-6
20
-8
0
0
20
40
60
80
100
120
140
OUTPUT POWER (mW)
-10
20
100
1k
10k 20k
FREQUENCY (Hz)
Figure 25.
Figure 26.
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Typical Performance Characteristics (continued)
Shutdown Hysterisis Voltage
VDD = 5V
Noise Floor
OUTPUT NOISE VOLTAGE (V)
100u
Vo1 + Vo2
10u
Shutdown On
1u
100n
20
100
1k
10k 20k
FREQUENCY (Hz)
Figure 27.
Figure 28.
Shutdown Hysterisis Voltage
VDD = 3V
ISD Distribution
VDD = 5V
1
0.9
DISTRIBUTION
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0
.005
.01
.015
.02 .025
.03 .035
SHUTDOWN CURRENT (PA)
Figure 29.
Figure 30.
ISD Distribution
VDD = 3V
1
0.9
DISTRIBUTION
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0
.002 .004 .006 .008 .01 .012 .014
SHUTDOWN CURRENT (PA)
Figure 31.
10
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APPLICATION INFORMATION
DIFFERENTIAL AMPLIFIER EXPLANATION
The LM4915 is a pseudo-differential audio amplifier that features a fixed gain of 6dB. Internally this is
accomplished by two separate sets of inverting amplifiers, each set to a gain of 2. The LM4915 features precisely
matched internal gain-setting resistors set to Ri = 20kΩ and Rf = 40kΩ, thus eliminating the need for external
resistors and fixing the differential gain at AVD = 6dB.
A differential amplifier works in a manner where the difference between the two input signals is amplified. In most
applications, this would require input signals that are 180° out of phase with each other. The LM4915 works in a
pseudo-differential manner, so DC offset normally cancelled by a fully differential amplifier needs to be blocked
by input coupling capacitors for the LM4915 to amplify the difference between the inputs.
The LM4915 provides what is known as a 'bridged mode' output (bridge-tied-load, BTL). This results in output
signals at Vo1 and Vo2 that are 180° out of phase with respect to each other. Bridged mode operation is different
from the single-ended amplifier configuration that connects the load between the amplifier output and ground. A
bridged amplifier design has distinct advantages over the single-ended configuration: it provides differential drive
to the load, thus doubling maximum possible output swing for a specific supply voltage. Four times the output
power is possible compared with a single-ended amplifier under the same conditions.
This increase in attainable output power assumes that the amplifier is not current limited or clipped. A bridged
configuration, such as the one used in the LM4915, 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. BTL configuration eliminates the output coupling capacitor required in single-supply, singleended amplifier configurations. If an output coupling capacitor is not used in a single-ended output configuration,
the half-supply bias across the load would result in both increased internal IC power dissipation as well as
permanent loudspeaker damage.
POWER DISSIPATION
Power dissipation is a major concern when designing a successful amplifer, whether the amplifier is bridged or
single-ended. Equation 1 states the maximum power dissipation point for a single-ended amplifier operating at a
given supply voltage and driving a specified output load.
PDMAX = (VDD) 2 / (2π2RL)
Single-Ended
(1)
However, a direct consequence of the increased power de-livered to the load by a bridge amplifier is an increase
in internal power dissipation versus a single-ended amplifier operating at the same conditions.
PDMAX = 4(VDD) 2 / (2π2RL)
Bridge Mode
(2)
Since the LM4915 has bridged outputs, the maximum internal power dissipation is 4 times that of a single-ended
amplifier.
Even with this substantial increase in power dissipation, the LM4915 does not require additional heatsinking
under most operating conditions and output loading. From Equation 2, assuming a 5V power supply and an 16Ω
load, the maximum power dissipation point is 316mW. The maximum power dissipation point obtained from
Equation 2 must not be greater than the power dissipation results from Equation 3:
PDMAX = (TJMAX - TA) / θJA
(3)
The LM4915's θJA in an NGP0008A package is 140°C/W. Depending on the ambient temperature, TA , of the
system surroundings, Equation 3 can be used to find the maximum internal power dissipation supported by the
IC packaging. If the result of Equation 2 is greater than that of Equation 3, then either the supply voltage must be
decreased, the load impedance increased, the ambient temperature reduced, or the θJA reduced with
heatsinking. In many cases, larger traces near the output, VDD, and GND pins can be used to lower the θJA. The
larger areas of copper provide a form of heatsinking allowing higher power dissipation. For the typical application
of a 5V power supply, with a 16Ω load power dissipation is not an issue. Recall that internal power dissipation is
a function of output power. If typical operation is not around the maximum power dissipation point, the LM4915
can operate at higher ambient temperatures. Refer to the Typical Performance Characteristics curves for
power dissipation information.
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POWER SUPPLY BYPASSING
As with any power amplifier, proper supply bypassing is critical for low noise performance and high power supply
rejection ratio (PSRR). The capacitor location on both the bypass and power supply pins should be as close to
the device as possible. A larger half-supply bypass capacitor improves PSRR because it increases half-supply
stability.
Typical applications employ a 5V regulator with 10µF and 0.1µF bypass capacitors that increase supply stability.
This, however, does not eliminate the need for bypassing the supply nodes of the LM4915. A 1µF capacitor is
recommended for CS. A 4.7µF capacitor is recommended for CB. This value coupled with small input capacitors
(0.1µF to 0.47µF) gives virtually zero click and pop with outstanding PSRR performance.
MICRO POWER SHUTDOWN
The voltage applied to the SHUTDOWN pin controls the LM4915's shutdown function. Activate micro-power
shutdown by applying a logic-low voltage to the SHUTDOWN pin. When active, the LM4915's micro-power
shutdown feature turns off the amplifier's bias circuitry, reducing the supply current. The trigger point is 0.4V for a
logic-low level, and 1.8V for a logic-high level. The low 0.1µA (typ) shutdown current is achieved by applying a
voltage that is as near as ground as possible to the SHUTDOWN pin. A voltage that is higher than ground may
increase the shutdown current. There are a few ways to control the micro-power shutdown. These include using
a single-pole, single-throw switch, a microprocessor, or a microcontroller. When using a switch, connect an
external 100k. pull-up resistor between the SHUTDOWN pin and VDD. Connect the switch between the
SHUTDOWN pin and ground. Select normal amplifier operation by opening the switch. Closing the switch
connects the SHUTDOWN pin to ground, activating micro-power shutdown.
The switch and resistor ensure that the SHUTDOWN pin will not float. This prevents unwanted state changes. In
a system with a microprocessor or microcontroller, use a digital output to apply the control voltage to the
SHUTDOWN pin. Driving the SHUTDOWN pin with active circuitry eliminates the pull-up resistor.
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 LM4915 is tolerant of external component combinations, and requires
minimal external components, consideration to component values must be used to maximize overall system
quality.
The input coupling capacitor, Ci, forms a first order high pass filter which limits low frequency response given by
fc = 1/(2πRiCi). Ri is internally set to 20kΩ. This value should be chosen based on needed frequency response
for a few distinct 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 100Hz to
150Hz. Thus, using a large input capacitor may not increase actual system performance.
In addition to system cost and size, click and pop performance is affected 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
LM4915 turns on. The slower the LM4915's outputs ramp to their quiescent DC voltage (nominally 1/2 VDD), the
smaller the turn-on pop. Choosing CB equal to 4.7µF along with a small value of CI (in the range of 0.1µF to
0.47µF), should produce a virtually clickless and popless shutdown function. While the device will function
properly, (no oscillations or motorboating), with CB equal to 1.0µF, the device will be much more susceptible to
turn-on clicks and pops. Thus, a value of CB equal to 4.7µF is recommended in all but the most cost sensitive
designs.
12
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Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LM4915
LM4915
www.ti.com
SNAS176A – MAY 2003 – REVISED MAY 2013
REVISION HISTORY
Changes from Original (May 2013) to Revision A
•
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 12
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Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LM4915
13
PACKAGE OPTION ADDENDUM
www.ti.com
2-May-2013
PACKAGING INFORMATION
Orderable Device
Status
(1)
LM4915LQX/NOPB
ACTIVE
Package Type Package Pins Package
Drawing
Qty
WQFN
NGP
8
4500
Eco Plan
Lead/Ball Finish
(2)
Green (RoHS
& no Sb/Br)
MSL Peak Temp
Op Temp (°C)
Top-Side Markings
(3)
CU SN
Level-3-260C-168 HR
(4)
-40 to 85
GA5
(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)
Multiple Top-Side Markings will be inside parentheses. Only one Top-Side 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 Top-Side Marking for that device.
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 1
Samples
PACKAGE MATERIALS INFORMATION
www.ti.com
8-May-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
LM4915LQX/NOPB
Package Package Pins
Type Drawing
WQFN
NGP
8
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
4500
330.0
12.4
Pack Materials-Page 1
2.2
B0
(mm)
K0
(mm)
P1
(mm)
2.2
1.0
8.0
W
Pin1
(mm) Quadrant
12.0
Q1
PACKAGE MATERIALS INFORMATION
www.ti.com
8-May-2013
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LM4915LQX/NOPB
WQFN
NGP
8
4500
367.0
367.0
35.0
Pack Materials-Page 2
MECHANICAL DATA
NGP0008A
LQB08A (Rev B)
www.ti.com
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