LM4900
265mW at 3.3V Supply Audio Power Amplifier with
Shutdown Mode
General Description
j THD+N at 1kHz for 675mW continuous
The LM4900 is a bridged audio power amplifier capable of
delivering 265mW of continuous average power into an 8Ω
load with 1% THD+N from a 3.3V power supply.
Boomer ® audio power amplifiers were designed specifically
to provide high quality output power from a low supply voltage while requiring a minimal amount of external components. Since the LM4900 does not require output coupling
capacitors, bootstrap capacitors or snubber networks, it is
optimally suited for low-power portable applications.
The LM4900 features an externally controlled, low power
consumption shutdown mode, and thermal shutdown protection.
The closed loop response of the unity-gain stable LM4900
can be configured by external gain-setting resistors.
average output power into 8Ω,
VDD = 5V
j Shutdown current
1.0% (max)
0.1µA (typ)
Features
n MSOP, LLP, and SOP packaging
n No output coupling capacitors, bootstrap capacitors, or
snubber circuits are necessary
n Thermal shutdown protection circuitry
n Unity-gain stable
n External gain configuration capability
n Latest generation "click and pop" suppression circuitry
Applications
Key Specifications
n Cellular phones
n PDA’s
n Any portable audio application
j THD+N at 1kHz for 265mW continuous
average output power into 8Ω,
VDD = 3.3V
1.0% (max)
Typical Application
20006401
FIGURE 1. Typical Audio Amplifier Application Circuit
Boomer ® is a registered trademark of National Semiconductor Corporation.
© 2004 National Semiconductor Corporation
DS200064
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LM4900 265mW at 3.3V Supply Audio Power Amplifier with Shutdown Mode
September 2001
LM4900
Connection Diagrams
MSOP and SOP Package
20006402
Top View
Order Number LM4900MM, LM4900M
See NS Package Number MUA08A, M08A
LLP Package
20006476
Top View
Order Number LM4900LD
See NS Package Number LDA08B
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2
See AN-450 “Surface Mounting and their Effects on
Product Reliability” for other methods of soldering surface
mount devices.
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Storage Temperature
Thermal Resistance
6.0V
θJC (M08A)
35˚C/W
−65˚C to +150˚C
θJA (M08A)
170˚C/W
Supply Voltage
−0.3V to VDD +
0.3V
θJC (MUA08A)
56˚C/W
θJA (MUA08A)
190˚C/W
Power Dissipation (Note 3)
Internally limited
θJA (LDA08B)
67˚C/W
ESD Susceptibility (Note 4)
2000V
ESD Susceptibility (Note 5)
200V
Input Voltage
Junction Temperature
Operating Ratings
150˚C
Temperature Range
Soldering Information
TMIN ≤ TA ≤ TMAX
Small Outline Package
Vapor Phase (60 sec.)
215˚C
Infrared (15 sec.)
220˚C
−40˚C ≤ TA ≤
+85˚C
2.0V ≤ VDD ≤ 5.5V
Supply Voltage
Electrical Characteristics (Note 1) (Note 2)
The following specifications apply for VDD = 5V, for all available packages, unless otherwise specified. Limits apply for TA =
25˚C
LM4900
Symbol
Parameter
Conditions
Typical
(Note 6)
Limit
(Notes 7,
9)
Units
(Limits)
4
6.0
mA (max)
0.1
5
µA (max)
IDD
Quiescent Power Supply Current
VIN = 0V, IO = 0A (Note 8)
ISD
Shutdown Current
VPIN1 = VDD
VOS
Output Offset Voltage
VIN = 0V
5
50
mV (max)
PO
Output Power
THD = 1% (max); f = 1kHz; RL = 8Ω;
675
300
mW (min)
THD+N
Total Harmonic Distortion+Noise
PO = 400 mWrms; AVD = 2; RL = 8Ω;
20Hz ≤ f ≤ 20kHz, BW < 80kHz
0.4
PSRR
Power Supply Rejection Ratio
VRIPPLE = 200mV sine p-p
f = 217Hz (Note 10)
70
f = 1KHz (Note 10)
67
f = 217Hz (Note 11)
55
f = 1KHz (Note 11)
55
%
dB
Electrical Characteristics (Note 1) (Note 2)
The following specifications apply for VDD = 3.3V, for all available packages, unless otherwise specified. Limits apply for TA =
25˚C
LM4900
Symbol
Parameter
Conditions
Typical
(Note 6)
Limit
(Notes 7,
9)
Units
(Limits)
IDD
Quiescent Power Supply Current
VIN = 0V, IO = 0A (Note 8)
ISD
Shutdown Current
VPIN1 = VDD
VOS
Output Offset Voltage
VIN = 0V
PO
Output Power
THD = 1% (max); f = 1kHz; RL = 8Ω;
265
mW (min)
THD+N
Total Harmonic Distortion+Noise
PO = 250 mWrms; AVD = 2; RL = 8Ω;
20Hz ≤ f ≤ 20kHz, BW < 80kHz
0.4
%
3
3
5
mA (max)
0.1
3
µA (max)
5
50
mV (max)
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LM4900
Absolute Maximum Ratings (Note 2)
LM4900
Electrical Characteristics (Note 1) (Note 2)
(Continued)
The following specifications apply for VDD = 3.3V, for all available packages, unless otherwise specified. Limits apply for TA =
25˚C
LM4900
Symbol
PSRR
Parameter
Power Supply Rejection Ratio
Conditions
Typical
(Note 6)
Limit
(Notes 7,
9)
Units
(Limits)
VRIPPLE = 200mV sine p-p
f = 217Hz (Note 10)
73
f = 1KHz (Note 10)
70
f = 217Hz (Note 11)
60
f = 1KHz (Note 11)
68
dB
Electrical Characteristics (Note 1) (Note 2)
The following specifications apply for VDD = 2.6V, for all available packages, unless otherwise specified. Limits apply for TA =
25˚C
LM4900
Symbol
Parameter
Conditions
Typical
(Note 6)
Limit
(Notes 7,
9)
Units
(Limits)
IDD
Quiescent Power Supply Current
VIN = 0V, IO = 0A (Note 8)
2.6
4
mA (max)
ISD
Shutdown Current
VPIN1 = VDD
0.1
2.0
µA (max)
VOS
Output Offset Voltage
VIN = 0V
PO
Output Power
THD+N
PSRR
Total Harmonic Distortion+Noise
Power Supply Rejection Ratio
5
mV
THD = 1% (max); f = 1kHz; RL = 8Ω
130
mW
PO = 100 mWrms; AVD = 2; RL = 8Ω;
20Hz ≤ f ≤ 20kHz, BW < 80kHz
0.4
%
VRIPPLE = 200mV sine p-p
f = 217Hz (Note 11)
58
f = 1KHz (Note 11)
63
dB
Note 1: All voltages are measured with respect to the ground pin, unless otherwise specified.
Note 2: 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 guarantee specific performance limits. Electrical Characteristics state DC and AC electrical specifications under particular test conditions which
guarantee specific performance limits. This assumes that the device is within the Operating Ratings. Specifications are not guaranteed for parameters where no limit
is given, however, the typical value is a good indication of device performance.
Note 3: 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 the Absolute Maximum Ratings, whichever is lower. For the LM4900, TJMAX = 150˚C.
The typical junction-to-ambient thermal resistance, when board mounted, is 190˚C/W for package number MUA08A.
Note 4: Human body model, 100pF discharged through a 1.5kΩ resistor.
Note 5: Machine Model, 220pF–240pF discharged through all pins.
Note 6: Typicals are measured at 25˚C and represent the parametric norm.
Note 7: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).
Note 8: The quiescent power supply current depends on the offset voltage when a practical load is connected to the amplifier.
Note 9: Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Note 10: Unterminated input.
Note 11: 10Ω terminated input.
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4
Components
LM4900
External Components Description
(Figure 1)
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 amplifier’s 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.
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 Proper Selection of External
Components for information concerning proper placement and selection of CB.
Typical Performance Characteristics
THD+N vs Frequency
THD+N vs Frequency
20006430
20006431
THD+N vs Frequency
THD+N vs Frequency
20006432
20006433
5
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LM4900
Typical Performance Characteristics
(Continued)
THD+N vs Frequency
THD+N vs Frequency
20006434
20006435
THD+N vs Frequency
THD+N vs Frequency
20006436
20006437
THD+N vs Frequency
THD+N vs Frequency
20006438
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20006439
6
LM4900
Typical Performance Characteristics
(Continued)
THD+N vs Frequency
THD+N vs Output Power
20006440
20006441
THD+N vs
Output Power
THD+N vs
Output Power
20006442
20006443
THD+N vs
Output Power
THD+N vs
Output Power
20006444
20006445
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LM4900
Typical Performance Characteristics
(Continued)
THD+N vs
Output Power
THD+N vs
Output Power
20006446
20006447
THD+N vs
Output Power
THD+N vs
Output Power
20006448
20006449
THD+N vs
Output Power
THD+N vs
Output Power
20006450
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20006451
8
LM4900
Typical Performance Characteristics
(Continued)
Output Power vs
Supply Voltage
Output Power vs
Supply Voltage
20006452
20006453
Output Power vs
Supply Voltage
Output Power vs
Supply Voltage
20006455
20006454
Output Power vs
Load Resistance
Power Dissipation vs
Output Power
20006456
20006457
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LM4900
Typical Performance Characteristics
(Continued)
Power Dissipation vs
Output Power
Power Dissipation vs
Output Power
20006459
20006458
Clipping Voltage vs
Supply Voltage
Noise Floor
20006460
20006461
Noise Floor
Frequency Response vs
Input Capacitor Size
20006471
20006462
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LM4900
Typical Performance Characteristics
(Continued)
Power Supply
Rejection Ratio
Power Supply
Rejection Ratio
20006463
20006464
Power Supply
Rejection Ratio
Power Supply
Rejection Ratio
20006465
20006466
Power Supply Rejection Ratio
vs Supply Voltage
Power Supply Rejection Ratio
vs Supply Voltage
20006467
20006468
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LM4900
Typical Performance Characteristics
(Continued)
Supply Current vs
Shutdown Voltage
LM4900MM Power Derating Curve
20006469
20006473
Supply Current vs
Supply Voltage
LM4900LD Power Derating Curve (Note 12)
20006475
20006470
Open Loop Frequency Response
20006472
Note 12: This curve shows the LM4900LD’s thermal dissipation ability at different ambient temperatures given the exposed-DAP of the part is soldered to a plane
of 1oz. Cu with an area given in the label of each curve.
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12
EXPOSED-DAP PACKAGE PCB MOUNTING
CONSIDERATION
A bridge configuration, such as the one used in LM4900,
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, single-ended amplifier configuration. If an output coupling capacitor is not used in a singleended configuration, the half-supply bias across the load
would result in both increased internal lC power dissipation
as well as permanent loudspeaker damage.
The LM4900’s exposed-DAP (die-attach paddle) package
(LD) provides a low thermal resistance between the die and
the PCB to which the part is mounted and soldered. This
allows rapid heat from the die to the surrounding PCB copper traces, ground plane, and surrounding air. This allows
the LM4900LD to operate at higher output power levels in
higher ambient temperatures than the MM package. Failing
to optimize thermal design may compromise the high power
performance and activate unwanted, though necessary,
thermal shutdown protection.
POWER DISSIPATION
Power dissipation is a major concern when designing a
successful amplifier, whether the amplifier is bridged or
single-ended. Equation 1 states the maximum power dissipation point for a bridge amplifier operating at a given supply
voltage and driving a specified output load.
Single-Ended (1)
PDMAX = (VDD)2/(2π2RL)
The LD package must have its DAP soldered to a copper
pad on the PCB. The DAP’s PCB copper pad is connected to
a large plane of continuous unbroken copper. This plane
forms a thermal mass, heat sink, and radiation area. Place
the heat sink area on either outside plane in the case of a
two-sided PCB, or on an inner layer of a board with more
than two layers. Connect the DAP copper pad to the inner
layer or backside copper heat sink area with 2 vias. The via
diameter should be 0.012in - 0.013in with a 1.27mm pitch.
Ensure efficient thermal conductivity by plating through the
vias.
However, a direct consequence of the increased power delivered to the load by a bridge amplifier is an increase in
internal power dissipation point for a bridge amplifier operating at the same conditions.
Bridge Mode (2)
PDMAX = 4(VDD)2/(2π2RL)
Since the LM4900 has two operational amplifiers in one
package, the maximum internal power dissipation is 4 times
that of a single-ended amplifier. Even with this substantial
increase in power dissipation, the LM4900 does not require
heatsinking. From Equation 1, assuming a 5V power supply
and an 8Ω load, the maximum power dissipation point is
625 mW. The maximum power dissipation point obtained
from Equation 2 must not be greater than the power dissipation that results from Equation 3:
(3)
PDMAX = (TJMAX − TA)/θJA
For package MUA08A, θJA = 190˚C/W. TJMAX = 150˚C for
the LM4900. 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 a higher power dissipation. For the typical application of a 5V power supply, with
an 8Ω load, the maximum ambient temperature possible
without violating the maximum junction temperature is approximately 30˚C provided that device operation is around
the maximum power dissipation point. Internal power dissipation is a function of output power. If typical operation is not
around the maximum power dissipation point, the ambient
temperature can be increased. Refer to the Typical Performance Characteristics curves for power dissipation information for lower output powers.
Best thermal performance is achieved with the largest practical heat sink area. The power derating curve in the Typical
Performance Characteristics shows the maximum power
dissipation versus temperature for several different areas of
heat sink area. Placing the majority of the heat sink area on
another plane is preferred as heat is best dissipated through
the bottom of the chip. Further detailed and specific information concerning PCB layout, fabrication, and mounting an LD
(LLP) package is available from National Semiconductor’s
Package Engineering Group under application note AN1187.
BRIDGE CONFIGURATION EXPLANATION
As shown in Figure 1, the LM4900 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 10 kΩ
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 180˚. Consequently, the differential gain for the IC
is
AVD = 2*(RF/Ri)
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 its load is connected to ground.
A bridge amplifier design has a few distinct advantages 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
POWER SUPPLY BYPASSING
As with any power 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. The effect of a larger half supply bypass capacitor
is improved PSRR due to increased half-supply stability.
13
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LM4900
choose an amplifier’s closed-loop gain without causing excessive clipping, please refer to the Audio Power Amplifier
Design section.
Application Information
LM4900
Application Information
systems, whether internal or external, have little ability to
reproduce signals below 150Hz. In this case using a large
input capacitor may not increase 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 LM4900 turns
on. The slower the LM4900’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 0.1µF to 0.39µF), should produce a clickless
and popless shutdown function. While the device will function properly, (no oscillations or motorboating), with CB equal
to 0.1µF, the device will be much more susceptible to turn-on
clicks and pops. Thus, a value of CB equal to 1.0µF or larger
is recommended in all but the most cost sensitive designs.
(Continued)
Typical applications employ a 5V regulator with 10µF and a
0.1µF bypass capacitors which aid in supply stability, but do
not eliminate the need for bypassing the supply nodes of the
LM4900. The selection of bypass capacitors, especially CB,
is thus dependent upon desired PSRR requirements, click
and pop performance as explained in the section, Proper
Selection of External Components, system cost, and size
constraints.
SHUTDOWN FUNCTION
In order to reduce power consumption while not in use, the
LM4900 contains a shutdown pin to externally turn off the
amplifier’s bias circuitry. This shutdown feature turns the
amplifier off when a logic high is placed on the shutdown pin.
The trigger point between a logic low and logic high level is
typically half supply. It is best to switch between ground and
supply to provide maximum device performance. By switching the shutdown pin to VDD, the LM4900 supply current
draw will be minimized in idle mode. While the device will be
disabled with shutdown pin voltages less than VDD, the idle
current may be greater than the typical value of 0.1µA. In
either case, the shutdown pin should be tied to a definite
voltage to avoid unwanted state changes.
In many applications, a microcontroller or microprocessor
output is used to control the shutdown circuitry which provides 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 enables the amplifier. If the switch is open, then the external
pull-up resistor will disable the LM4900. This scheme guarantees that the shutdown pin will not float, thus preventing
unwanted state changes.
AUDIO POWER AMPLIFIER DESIGN
Design a 300 mW/8Ω Audio Amplifier
Given:
Power Output
300mWrms
Load Impedance
1Vrms
Input Impedance
20kΩ
100Hz–20 kHz ± 0.25dB
Bandwidth
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 LM4900 is tolerant to a
variety of external component combinations, consideration
to component values must be used to maximize overall
system quality.
The LM4900 is unity-gain stable, giving a designer maximum
system flexibility. The LM4900 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 closedloop 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 distinct reasons.
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 4
and add the dropout voltage. Using this method, the minimum supply voltage would be (Vopeak + (2*VOD)), where VOD
is extrapolated from the Dropout Voltage vs Supply Voltage
curve in the Typical Performance Characteristics section.
(4)
Using the Output Power vs Supply Voltage graph for an 8Ω
load, the minimum supply rail is 3.5V. But since 5V is a
standard supply voltage in most applications, it is chosen for
the supply rail. Extra supply voltage creates headroom that
allows the LM4900 to reproduce peaks in excess of 700 mW
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 5.
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
(5)
RF/Ri = AVD/2
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8Ω
Input Level
14
(6)
LM4900
Application Information
(Continued)
From Equation 5, the minimum AVD is 1.55; use AVD = 2.
Since the desired input impedance was 20 kΩ, and with a
AVD of 2, a ratio of 1:1 of RF to Ri results in an allocation of
Ri = RF = 20 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 pole gives
0.17 dB down from passband response which is better than
the required ± 0.25 dB specified.
fL = 100Hz/5 = 20Hz
fH = 20kHz x 5 = 100kHz
As stated in the External Components section, Ri in conjunction with Ci create a highpass filter.
Ci ≥ 1/(2π*20 kΩ*20 Hz) = 0.397µF;
use 0.39µF
The high frequency pole is determined by the product of the
desired high frequency pole, fH, and the differential gain,
AVD. With a AVD = 2 and fH = 100kHz, the resulting GBWP =
100kHz which is much smaller than the LM4900 GBWP of
25MHz. This figure displays that if a designer has a need to
design an amplifier with a higher differential gain, the
LM4900 can still be used without running into bandwidth
problems.
20006474
FIGURE 2. Differential Amplifier Configuration for LM4900
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LM4900
Physical Dimensions
inches (millimeters) unless otherwise noted
8-Lead (0.118" Wide) Molded Mini Small Outline Package
Order Number LM4900MM
NS Package Number MUA08A
Order Number LM4900LD
NS Package Number LDA08B
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16
inches (millimeters) unless otherwise noted (Continued)
SO
Order Number LM4900M
NS Package Number M08A
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves
the right at any time without notice to change said circuitry and specifications.
For the most current product information visit us at www.national.com.
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WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR
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which, (a) are intended for surgical implant into the body, or
(b) support or sustain life, and whose failure to perform when
properly used in accordance with instructions for use
provided in the labeling, can be reasonably expected to result
in a significant injury to the user.
2. A critical component is any component of a life support
device or system whose failure to perform can be reasonably
expected to cause the failure of the life support device or
system, or to affect its safety or effectiveness.
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National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship
Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned
Substances’’ as defined in CSP-9-111S2.
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LM4900 265mW at 3.3V Supply Audio Power Amplifier with Shutdown Mode
Physical Dimensions
