TEA7532DP datasheet(6/16 Pages) STMICROELECTRONICS

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CIRCUIT DESCRIPTION

TEA7532 is a 16 pin DIL integrated circuit providing

the following facilities :

- Loudspeaker amplifier

- Antiacoustic feed-back system

(antilarsen system)

1.1. LOUDSPEAKER AMPLIFIER

Figure 11.

The amplifier is divided into 3 main sections.

- AutomaticGain Control (AGC)

- Preamplifier

- Push-pull amplifier (bridge structure)

a) The AGC section is used for the antilarsen and

antidistortion system.

• When used in a telephone set to avoid larsen ef-

fect the AGC automatically decreases loud-

speaker amplifier gain.

• When the required output level exceeds the

capabilities of the available current, the AGC

decreases the loudspeaker amplifier gain to

avoid distortion.

b) The preamplifier permits step control of amplifier

gain in steps of 6 dB, using pins PG0 and PG1,

which may be controlled using switches or by a mi-

croprocessor. The amplifier may be muted using the

ON/OFF control signal (pin 16).

c) The output amplifier uses a double push-pull con-

figuration(H bridge) to get maximum dynamic range

under limited supply conditions.

Figure 12.

TEA7532

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TEA7532DP Datasheet(PDF) 6 Page - STMicroelectronics