Stereo High Fidelity 200 Volt* Driver with Mute

General Description

The LM4702 is a high fidelity audio power amplifier driver

designed for demanding consumer and pro-audio applica-

tions. Amplifier output power may be scaled by changing the

supply voltage and number of output devices. The LM4702

is capable of delivering in excess of 300 watts per channel

single ended into an 8 ohm load in the presence of 10% high

line headroom and 20% supply regulation.

The LM4702 includes thermal shut down circuitry that acti-

vates when the die temperature exceeds 150˚C. The

LM4702’s mute function, when activated, mutes the input

drive signal and forces the amplifier output to a quiescent

state.

The LM4702 is available in 3 grades that span a wide range

of applications and performance levels. The LM4702C is

targeted at high volume applications. The LM4702B (in de-

velopment) includes a higher voltage rating along with the

tighter specifications. The LM4702A (in development) is the

premium part with the highest voltage rating, fully specified

with limits over voltage and temperature, and is offered in a

military 883 compliant TO-3 package.

* Tentative Max Operating voltage for the LM4702A,

LM4702B (in development)

Key Specifications

LM4702A (in development)

LM4702B (in development)

LM4702C

3µV

110dB (typ)

0.001%

Features

n

Very high voltage operation

n

Scalable output power

n

Minimum external components

n

External compensation

n

Thermal Shutdown and Mute

Applications

n

AV receivers

n

Audiophile power amps

n

Pro Audio

n

High voltage industrial applications

Typical Application and Connection Diagrams

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FIGURE 1. Typical Audio Amplifier Application Circuit

20158302

Plastic Package — 15 Lead TO-220

(for LM4702; LM4702B, in development)

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Metal Can — 15 Lead TO-3

(for LM4702A, in development)

September 2005

© 2005 National Semiconductor Corporation

DS201583

www.national.com