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Audio ICs

Dual preamplifier with ALC

BA3311L

The BA3311L is a dual preamplifier with ALC designed for use in stereo radio-cassette recorders. It comes in a compact

12-pin ZIP package and has two record / playback preamplifiers, and an ALC circuit. The preamplifiers are directly

coupled to the head and do not require coupling capacitors. This prevents tape head magnetization and ”pop” noise

generation.

An ALC circuit with large dynamic range can be constructed with addition of just an external detector and time constant

circuit.

FApplications

Stereo radio cassette players

FFeatures

1) The input block uses a bias circuit that does not re-

quire coupling capacitors.

2) ALC circuit requires addition of just an external de-

tector and time constant circuit.

3) Wide operating power supply voltage range.

4) High gain.

5) Low noise.

FBlock diagram