LM4941, LM4941SDBD, LM4941TMBD

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SNAS347C – JUNE 2006 – REVISED MAY 2013

LM4941

1.25 Watt Fully Differential Audio Power Amplifier

With RF Suppression and Shutdown

Check for Samples: LM4941, LM4941SDBD, LM4941TMBD

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FEATURES

DESCRIPTION

The LM4941 is a fully differential audio power

2

•

Improved RF Suppression, By Up to 20dB

amplifier

primarily

designed

for

demanding

Over Previous Designs in Selected

applications in mobile phones and other portable

Applications

communication device applications. It is capable of

•

Fully Differential Amplification

delivering 1.25 watts of continuous average power to

a 8

Ω load with less than 1% distortion (THD+N) from

•

Available in Space-Saving DSBGA Package

a 5VDC power supply. The LM4941 does not require

•

Ultra Low Current Shutdown Mode

output coupling capacitors or bootstrap capacitors,

•

Can Drive Capacitive Loads up to 100pF

and therefore is ideally suited for mobile phone and

•

Improved Pop & Click Circuitry Eliminates

other small form factor applications where minimal

PCB space is a primary requirement.

Noises During Turn-On and Turn-Off

Transitions

The

LM4941

also

features

proprietary

internal

•

2.4 - 5.5V Operation

circuitry that suppresses the coupling of RF signals

into the chip. This is important because certain types

•

No Output Coupling Capacitors, Snubber

of RF signals (such as GSM) can couple into audio

Networks or Bootstrap Capacitors Required

amplifiers in such a way that part of the signal is

heard through the speaker. The RF suppression

APPLICATIONS

circuitry in the LM4941 makes it well-suited for

•

Mobile Phones

portable applications in which strong RF signals

generated by an antenna from or a cellular phone or

•

PDAs

other portable electronic device may couple audibly

•

Portable Electronic Devices

into the amplifier.

Other features include a low-power consumption

KEY SPECIFICATIONS

shutdown

mode,

internal

thermal

shutdown

•

Improved PSRR at 217Hz 95dB (typ)

protection, and advanced pop & click circuitry.

•

Power Output, VDD = 5.0V, RL = 8Ω, 1% THD+N

1.25W (typ)

•

Power Output, VDD = 3.0V, RL = 8Ω, 1% THD+N

430mW (typ)

•

Shutdown Current 0.1µA (typ)

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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2

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PRODUCTION DATA information is current as of publication date.

Copyright © 2006–2013, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.