ROHM BH3540AFS Datasheet

Optical disc ICs

Headphone amplifier with
internal LPF and EVR for CD-ROM

BH3540AFS

The BH3540AFS is an H / P amplifier with internal secondary LPF and EVR circuits. When multibit output from a
D/A converter is input, the secondary LPF outputs an audio signal. Output level for headphones can be changed with
the EVR circuit. This IC also has independent internal mute circuits for the left and right channels.

Applications
CD-ROM drives and other products (with line and headphone output pins) that process digital audio signals

Features

1) Internal LPF, line amplifier and EVR.

2) Internal mute function.

3) Internal thermal shutdown circuit.

Block diagram

4) No attached oscillation prevention components are
needed, even at a load of 8Ω.

5) Mute function reduces the popping noises that can
occur when the power is turned on and off.

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Optical disc ICs BH3540AFS

FAbsolute maximum ratings (Ta = 25_C) FRecommended operating conditions

FElectrical characteristics (unless otherwise noted, Ta = 25_C, V

IN = 1.8dBV, f = 1kHz, EVR = Max.)

V

CC = 5.0V, line RL1 = 50kΩ, H/P RL2 = 32Ω,

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