Datasheet LM4877IBP Datasheet (NSC)

February 2000

LM4877

1 Watt Audio Power Amplifier in micro SMD package
with Shutdown Logic Low

LM4877 1 Watt Audio Power Amplifier micro SMD package with Shutdown Logic Low

General Description

The LM4877 is a bridge-connected audio power amplifier ca­pable of delivering1Wofcontinuous average power to an
8Ω load with less than .2% (THD) from a 5V power supply.

Boomer audio power amplifiers were designed specifically to
provide high quality output power with a minimal amount of
external components. Since the LM4877 does not require
output coupling capacitors or bootstrap capacitors. It is opti­mally suited for low-power portable applications.

The LM4877 features an externally controlled, low-power
consumption shutdown mode, as well as an internal thermal
shutdown protection mechanism.

The unity-gain stable LM4877 can be configured by external
gain-setting resistors.

Key Specifications

n Power Output at 0.2% THD 1 W (typ)
n Shutdown Current 0.01 µA (typ)

Features

n micro SMD package (see App. note AN-1112)
n 5V - 2V operation
n No output coupling capacitors or bootstrap capacitors.
n Unity-gain stable
n External gain configuration capability

Applications

n Cellular Phones
n Portable Computers
n Low Voltage Audio Systems

Typical Application Connection Diagram

8 Bump micro SMD

DS101290-23

Top View

Order Number LM4877IBP, LM4877IBPX

See NS Package Number BPA08B6B

DS101290-1

FIGURE 1. Typical Audio Amplifier Application Circuit

Boomer®is a registered trademark of National Semiconductor Corporation.

© 2000 National Semiconductor Corporation DS101290 www.national.com

Absolute Maximum Ratings (Note 2)

If Military/Aerospace specified devices are required,

LM4877

please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.

Supply Voltage 6.0V
Storage Temperature −65˚C to +150˚C
Input Voltage −0.3V to V

DD

+0.3V
Power Dissipation (Note 3) Internally Limited
ESD Susceptibility (Note 4) 2500V
ESD Susceptibility (Note 5) 250V
Junction Temperature 150˚C

Electrical Characteristics VDD=5V(Notes 1, 2, 9)

The following specifications apply for V

= 5V and 8Ω Load unless otherwise specified. Limits apply for TA= 25˚C.

DD

Soldering Information
See AN-1112 ″Micro-SMD Wafers Level Chip Scale

Package″.

Operating Ratings

Temperature Range

T

≤ TA≤ T

MIN

MAX

Supply Voltage 2.0V ≤ V

−40˚C ≤ TA≤ 85˚C

DD

≤ 5.5V

Symbol Parameter Conditions

V

DD

I

DD

I

SD

V

OS

P

o

THD+N Total Harmonic Distortion+Noise P

Supply Voltage 2.0 V (min)

Quiescent Power Supply Current VIN= 0V, Io= 0A 5.3 7 mA (max)
Shutdown Current V

= 0V 0.01 2 µA (max)

PIN5

Output Offset Voltage VIN= 0V 5 50 mV (max)
Output Power THD = 0.2% (max);f=1kHz 1 W

= 0.25 Wrms; AVD=2;20Hz≤

o

f≤20 kHz

PSRR Power Supply Rejection Ratio V

= 4.9V to 5.1V 65 dB

DD

Electrical Characteristics VDD= 3.3V (Notes 1, 2, 9)

The following specifications apply for V

Symbol Parameter Conditions

V

DD

I

DD

I

SD

V

OS

P

o

Supply Voltage 2.0 V (min)

Quiescent Power Supply Current VIN= 0V, Io= 0A 4 mA (max)
Shutdown Current V
Output Offset Voltage VIN= 0V 5 mV (max)
Output Power THD = 1% (max);f=1kHz .5 .45 W

THD+N Total Harmonic Distortion+Noise P

PSRR Power Supply Rejection Ratio V

= 3.3V and 8Ω Load unless otherwise specified. Limits apply for TA= 25˚C.

DD

= 0V 0.01 µA (max)

PIN5

= 0.25 Wrms; AVD=2;20Hz≤

o

f≤20 kHz

= 3.2V to 3.4V 65 dB

DD

LM4877

Typical Limit

(Note 6) (Note 7)

5.5 V (max)

0.1 %

LM4877

Typical Limit

(Note 6) (Note 7)

5.5 V (max)

0.15 %

Units

(Limits)

Units

(Limits)

Electrical Characteristics VDD= 2.6V (Notes 1, 2, 8, 9)

The following specifications apply for V

Symbol Parameter Conditions

V

DD

I

DD

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Supply Voltage 2.0 V (min)

Quiescent Power Supply Current VIN= 0V, Io= 0A 3.4 mA (max)

= 2.6V and 8Ω Load unless otherwise specified. Limits apply for TA= 25˚C.

DD

LM4877

Typical Limit

(Note 6) (Note 7)

5.5 V (max)

Units

(Limits)

Electrical Characteristics VDD= 2.6V (Notes 1, 2, 8, 9)

The following specifications apply for V
25˚C. (Continued)

= 2.6V and 8Ω Load unless otherwise specified. Limits apply for TA=

DD

LM4877

Symbol Parameter Conditions

I

SD

V

OS

P

0

Shutdown Current V
Output Offset Voltage VIN= 0V 5 mV (max)
Output Power ( 8Ω )

Output Power ( 4Ω )

THD+N Total Harmonic Distortion+Noise P

= 0V 0.01 µA (max)

PIN5

THD = 0.3% (max);f=1kHz
THD = 0.5% (max);f=1kHz

= 0.25 Wrms; AVD=2;20Hz≤

o

LM4877

Typical Limit

(Note 6) (Note 7)

0.25

0.5

0.25 %

Units

(Limits)

f≤20 kHz

PSRR Power Supply Rejection Ratio V

Note 1: All voltages are measured with respect to the ground pin, unless otherwise specified.
Note 2:

Absolute Maximum Ratings

tional, but do not guarantee specific performance limits.
antee 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 T
allowable power dissipation is P
typical junction-to-ambient thermal resistance is 150˚C/W.

Note 4: Human body model, 100 pF discharged through a 1.5 kΩ resistor.
Note 5: Machine Model, 220 pF–240 pF 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: Low Voltage Circuit - See Fig. 4
Note 9: Shutdown current is measured in a Normal Room Environment. Exposure to direct sunlight will increase I

indicate limits beyond which damage to the device may occur.

=(T

DMAX

JMAX–TA

Electrical Characteristics

)/θJAor the number given in Absolute Maximum Ratings, whichever is lower. For the LM4877, T

= 2.5V to 2.7V 65 dB

DD

state DC andAC electrical specifications under particular test conditions which guar-

Operating Ratings

JMAX

indicate conditions for which the device is func-

, θJA, and the ambient temperature TA. The maximum

by a maximum of 2µA.

SD

JMAX

= 150˚C. The

Electrical Characteristics VDD= 5/3.3/2.6V Shutdown Input

W
W

Symbol Parameter Conditions

V

IH

V

IL

External Components Description (

Shutdown Input Voltage High 1.2 V(min)
Shutdown Input Voltage Low 0.4 V(max)

Figure 1

)

Components Functional Description

1. R

2. C

3. R

4. C

Inverting input resistance which sets the closed-loop gain in conjunction with Rf. This resistor also forms a

i

high pass filter with C
Input coupling capacitor which blocks the DC voltage at the amplifiers input terminals. Also creates a

i

highpass filter with R
for an explanation of how to determine the value of C

Feedback resistance which sets the closed-loop gain in conjunction with Ri.

f

Supply bypass capacitor which provides power supply filtering. Refer to the Power Supply Bypassing

S

at fC= 1/(2π RiCi).

i

at fc= 1/(2π RiCi). Refer to the section, Proper Selection of External Components,

i

.

i

section for information concerning proper placement and selection of the supply bypass capacitor.

5. C

Bypass pin capacitor which provides half-supply filtering. Refer to the section, Proper Selection of External

B

Components, for information concerning proper placement and selection of C

LM4877

Typical Limit

.

B

Units

(Limits)

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Typical Performance Characteristics

LM4877

THD+N vs Frequency
at 5V and 8Ω

THD+N vs Frequency
at 3.3V and 8Ω

THD+N vs Frequency
at 2.6V and 8Ω

THD+N vs Output Power
V

=5V

DD

DS101290-3

DS101290-5

THD+N vs Frequency
at 2.6V and 4Ω

THD+N vs Output Power
V

= 3.3V

DD

DS101290-6

DS101290-4

DS101290-7

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DS101290-8

Typical Performance Characteristics (Continued)

LM4877

THD+N vs
Output Power

2.6V at 8Ω

Output Power vs
Supply Voltage

DS101290-9

THD+N vs
Output Power

2.6V at 4Ω

DS101290-10

Output Power vs
Load Resistance

Power Derating Curve

DS101290-11

DS101290-14

Power Dissipation vs
Output Power
V

=5V

DD

DS101290-12

DS101290-26

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Typical Performance Characteristics (Continued)

LM4877

Power Dissipation vs
Output Power
V

= 3.3V

DD

Power Dissipation vs
Output Power
V

= 2.6V

DD

Clipping Voltage vs
Supply Voltage

Frequency Response vs
Input Capacitor Size

DS101290-27

DS101290-15

Supply Current vs
Shutdown Voltage
LM4877

@

VDD = 5/3.3/2.6V

Power Supply
Rejection Ratio

DS101290-28

dc

DS101290-35

DS101290-17

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DS101290-18

Typical Performance Characteristics (Continued)

Open Loop
Frequency Response

Noise Floor

LM4877

DS101290-19

DS101290-16

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Application Information

LM4877

BRIDGE CONFIGURATION EXPLANATION

As shown in
plifiers 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 R
the second amplifier’s gain is fixed by the two internal 10 kΩ
resistors.
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

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
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 LM4877,
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. 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 single­ended. A direct consequence of the increased power deliv­ered to the load by a bridge amplifier is an increase in
internal power dissipation. Since the LM4877 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 1.

It is critical that the maximum junction temperature T
150˚C is not exceeded. T
power derating curves by using P
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 P
can be added to any of the leads connected to the LM4877.
It is especially effective when connected to V
the output pins. Refer to the application information on the
LM4877 reference design board for an example of good heat
sinking. If T
changes must be made. These changes can include re-

Figure 1

Figure 1

P

DMAX

JMAX

, the LM4877 has two operational am-

shows that the output of amplifier one

A

= 2 *(Rf/Ri)

VD

= 4*(VDD)2/(2π2RL) (1)

can be determined from the

JMAX

and the PC board foil

DMAX

. Additional copper foil

DMAX

still exceeds 150˚C, then additional

to Riwhile

f

DD,GND

JMAX

, and

duced supply voltage, higher load impedance, or reduced
ambient temperature. The National Reference Design board
using a 5V supply and an 8 ohm load will run in a 110˚C am­bient environement without exceeding T

. Internal power

JMAX

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. Typicalapplica­tions employ a 5V regulator with 10 µF Tantalum or electro­lytic capacitor and a 0.1 µF bypass capacitor which aid in
supply stability. This does not eliminate the need for bypass­ing the supply nodes of the LM4877. The selection of a by­pass capacitor, especially C

, is dependent upon PSRR re-

B

quirements, 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
LM4877 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 LM4877 supply
current draw will be minimized in idle mode. While the device
will be disabled with shutdown pin voltages less than

0.4V

, the idle current may be greater than the typical

DC

value of 0.01 µA.
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 disables the
amplifier. If the switch is open, then the external pull-up re­sistor will enable the LM4877. This scheme guarantees that
the shutdown pin will not float thus preventing unwanted
state changes. Another way to operate the shutdown circuit
is with a pulldown resistor (R

), as shown in the applications

1

circuit on Figure 3. J1 operates the shutdown function. J1
must be installed to operate the part. A switch may be in­stalled in place of J1 for easier evaluation of the shutdown
function.

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 LM4877 is tolerant of
external component combinations, consideration to compo­nent values must be used to maximize overall system qual-

of

ity.
The LM4877 is unity-gain stable which gives a designer

maximum system flexibility. The LM4877 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 band-

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Application Information (Continued)

width is dictated by the choice of external components
shown in
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.

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,
C
reach its quiescent DC voltage (nominally 1/2 V
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, C
turn-on pops since it determines how fast the LM4877 turns
on. The slower the LM4877’s outputs ramp to their quiescent
DC voltage (nominally 1/2 V
Choosing C
(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
C
to turn-on clicks and pops. Thus, a value of C

1.0 µF is recommended in all but the most cost sensitive de­signs.

LOW VOLTAGE APPLICATIONS ( BELOW 3.0 V

The LM4877 will function at voltages below 3 volts but this
mode of operation requires the addition of a 1kΩ resistor
from each of the differential output pins ( pins 8 and4)di­rectly to ground.The addition of the pair of 1kΩ resistors ( R4
& R5 ) assures stable operation below 3 Volt Vdd operation.
The addition of the two resistors will however increase the
idle current by as much as 5mA. This is because at 0v input
both of the outputs of the LM4877’s 2 internal opamps go to
1/2 V
flow through the 1K resistors from output to ground. See fig

4.
Jumper options have been included on the reference design,

Fig. 4, to accommodate the low voltage application. J2 & J3
connect R4 and R5 to the outputs.

Figure 1

A larger input coupling capacitor requires more charge to

i.

equal to 0.1 µF,the device will be much more susceptible

B

( 2.5 volts for a 5v power supply ), causingcurrent to

DD

. The input coupling capacitor, Ci, forms a

). This

DD

, is the most critical component to minimize

B

), the smaller the turn-on pop.

equal to 1.0 µF along with a small value of C

B

DD

equal to

B

)

DD

LM4877

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

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 Per-
formance Characteristics section, the supply rail can be
easily found. A second way to determine the minimum sup­ply rail is to calculate the required V

opeak

and add the output voltage. Using this method, the minimum
supply voltage would be (V
V

and V

OD

BOT

age vs Supply Voltage curve in the Typical Performance

are extrapolated from the Dropout Volt-

OD

TOP

opeak

+(V

OD

TOP

Characteristics section.

Using the Output Power vs Supply Voltage graph for an 8Ω
load, the minimum supply rail is 4.6V. But since 5V is a stan­dard voltage in most applications, it is chosen for the supply
rail. Extra supply voltage creates headroom that allows the
LM4877 to reproduce peaks in excess of 1W without produc­ing audible distortion. At this time, the designer must make

i

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 3.

R

f/Ri=AVD

From Equation 3, the minimum A

/2

is 2.83; use AVD=3.

VD

Since the desired input impedance was 20 kΩ, and with a
A

impedance of 2, a ratio of 1.5:1 of Rfto Riresults in an

VD

allocation of R

=20kΩand Rf=30kΩ. The final design step

i

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

f

= 100 Hz/5 = 20 Hz

L

f

=20kHz*5=100kHz

H

±

0.25 dB specified.

As stated in the External Components section, R
junction with C

C

≥ 1/(2π*20 kΩ*20 Hz) = 0.397 µF; use 0.39 µF

i

create a highpass filter.

i

The high frequency pole is determined by the product of the
desired frequency pole, f
With a A

= 3 and fH= 100 kHz, the resulting GBWP =

VD

, and the differential gain, AVD.

H

150 kHz which is much smaller than the LM4877 GBWP of
4 MHz. This figure displays that if a designer has a need to
design an amplifier with a higher differential gain, the
LM4877 can still be used without running into bandwidth limi­tations.

±

0.25 dB

using Equation 2

+V

OD

)), where

BOT

i

in con-

(2)

(3)

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Application Information (Continued)

HIGHER GAIN AUDIO AMPLIFIER

LM4877

The LM4877 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 may be needed as
shown in Figure 2 to bandwidth limit the amplifier.This feed­back capacitor creates a low pass filter that eliminates

Figure 2

DS101290-24

possible high frequency oscillations. Care should be taken
when calculating the -3dB frequency in that an incorrect
combination of R

and C4will cause rolloff before 20kHz. A

3

typical combination of feedback resistor and capacitor that
will not produce audio band high frequency rolloff is R
20kΩ and C

= 25pf. These components result in a -3dB

4

3

point of approximately 320 kHz. It is not recommended that
the feedback resistor and capacitor be used to implement a
band limiting filter below 100kHZ.

=

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Application Information (Continued)

DIFFERENTIAL AMPLIFIER CONFIGURATION FOR
LM4877

LM4877

DS101290-29

Figure 3

Mono LM4877 Reference Design Board - Assembly Part Number:
980011207-100 Revision: A Bill of Material

Item Part Number Part Description Qty Ref Designator

1 551011208-001 LM4877 Mono Reference

Design Board PCB etch 001

10 482911183-001 LM4877 Audio AMP micro

SMD 8 Bumps

20 151911207-001 Cer Cap 0.1uF 50V +80/-20
21 151911207-002 Cer Cap 0.39uF 50V Z5U 20
25 152911207-001 Tant Cap 1uF 16V 10
30 472911207-001 Res 20K Ohm 1/10W 5
31 472911207-002 Res 1K Ohm 1/10W 5

1206

1210

Size=A3216

0805

0805

35 210007039-002 Jumper Header Vertical

Mount 2X1 0.100

36 210007582-001 Jumper Shunt 2 position

0.100

1

1U1

1C1
1C2
1C3
3 R1, R2, R3
2 R4, R5,
3 J1, J2, J3

3

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Application Information (Continued)

LM4877

Silk Screen

Top Layer

Bottom Layer

Inner Layer Ground

DS101290-30

DS101290-32

Inner Layer V

DS101290-31

DD

DS101290-33

DS101290-34

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Application Information (Continued)

REFERENCE DESIGN BOARD and PCB LAYOUT
GUIDELINES

LM4877

PCB Layout Guidelines

This section provides practical guidelines for mixed signal
PCB layout that involves various digital/analog power and
ground traces. Designers should note that these are only
″rule-of-thumb″ recommendations and the actual results will
depend heavily on the final layout.

General Mixed Signal Layout Recommendation

Power and Ground Circuits

For 2 layer mixed signal design, it is important to isolate the
digital power and ground trace paths from the analog power
and ground trace paths. Star trace routing techniques (bring­ing individual traces back to a central point rather than daisy
chaining traces together in a serial manner) can have a ma­jor impact on low level signal performance. Star tracerouting
refers to using individual traces to feed power and ground to
each circuit or even device. This technique will take require
a greater amount of design time but will not increase the final
price of the board. The only extra parts required will be some
jumpers.

DS101290-25

Figure 4

Single-Point Power / Ground Connections

The analog power traces should be connected to the digital
traces through a single point (link). A ″Pi-filter″ can be helpful
in minimizing High Frequency noise coupling between the
analog and digital sections. It is further recommended to put
digital and analog power traces over the corresponding digi­tal and analog ground traces to minimize noise coupling.

Placement of Digital and Analog Components

All digital components and high-speed digital signals traces
should be located as far away as possible from the analog
components and the analog circuit traces.

Avoiding Typical Design / Layout Problems

Avoid ground loops or running digital and analog traces par­allel to each other (side-by-side) on the same PCB layer.
When traces must cross over each other do it at 90 degrees.
Running digital and analog traces at 90 degrees to each
other from the top to the bottom side as much as possible will
minimize capacitive noise coupling and cross talk.

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Physical Dimensions inches (millimeters) unless otherwise noted

Note: Unless otherwise specified.

1. Epoxy coating.

2. 63Sn/37Pb eutectic bump.

3. Recommend non-solder mask defined landing pad.

4. Pin 1 is established by lower left corner with respect to text orientation pins are numbered counterclockwise.

5. Reference JEDEC registration MO-211, variation BC.

8-Bump micro SMD

Order Number LM4877IBP, LM4877IBPX

NS Package Number BPA08B6B

X

= 1.31 X2= 1.97 X3= 0.850

1

LIFE SUPPORT POLICY

NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:

1. Life support devices or systems are devices or
systems 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

LM4877 1 Watt Audio Power Amplifier micro SMD package with Shutdown Logic Low

labeling, can be reasonably expected to result in a

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.

significant injury to the user.

National Semiconductor
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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.

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