ROHM BA3423S Datasheet

Audio ICs

Double cassette tape recorder system
preamplifier

BA3423S

The BA3423S is a record/playback system preamplifier for radio cassette decks. With four control pins it allows switch­ing between I/O for the A (play only) and B (record and play) mechanisms, input for tape, radio, and microphone, on
and off switching for line out and recording output, and equalizer switching for normal and high-speed dubbing.
It requires about half the number of external components of its predecessors which means simplified assembly and over­all cost savings.

Applications
Dual-cassette radio cassette players.

Features

1) Built-in switch for playback equalizer amplifier for the
A and B mechanisms.

2) Built-in normal / high-speed equalizer switch for the
playback equalizer amplifier.

3) The B mechanism input is also used as the recording
output, so a switch is not required.

4) Built-in tape/radio input switch, and microphone mix­ing.

5) The microphone amplifier is used as the mixing am­plifier, and the line can be muted to allow the built-in
microphone to be used for recording.

6) Built-in ALC circuit.

7) Built-in recording equalizer circuit, and internal
switching of the normal/ high-speed equalizer is
possible.

8) All stages are directly connected, so coupling ca­pacitors are not required.

9) Muting is applied as required during switching to re­duce switching noise (transition muting).

10) Pin assignments has been designed to facilitate
placement of attached components and PCB de­sign.

Absolute maximum ratings (Ta = 25C)

Recommended operating conditions (Ta = 25C)

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Audio ICs BA3423S

Block diagram

Pin assignments

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Audio ICs BA3423S

Pin descriptions

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Audio ICs BA3423S

Input / output circuits

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Audio ICs BA3423S

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Audio ICs BA3423S

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