ROHM BA3870 Datasheet

Audio ICs

BBS (bass boost system) for radio
cassette players

BA3870

The BA3870 is a bass boost audio IC for radio cassette players. BBS adjusts the base boost to a level appropriate for
the volume, achieving a rich sound without distortion. Frequency characteristics can be set externally, enabling system
design to meet the needs of the application.

Applications
Radio cassette players

Features

1) Adjustment of the base boost to a level appropriate
for the volume through BBS.

2) Maximum bass boost level can be set externally.
(20dB recommended)

3) Treble boost circuit (constant at 4dB) included on­chip to preserve overall balance.

4) BBS on/off “pop” sound almost nonexistent.

Absolute maximum ratings (Ta = 25C)

Recommended operating conditions (Ta = 25C)

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Audio ICs BA3870

Block diagram

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Audio ICs BA3870

Pin descriptions

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Audio ICs BA3870

Input/output circuits

Electrical characteristics (unless otherwise noted, Ta = 25C, V

CC = 5.0V and f = 1kHz)

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Audio ICs BA3870

Measurement circuit

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