○Product structure：Silicon monolithic integrated circuit ○This product has no designed protection against radioactive rays

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TSZ02201-0C2C0E100520-1-2

© 2015 ROHM Co., Ltd. All rights reserved.

TSZ22111・14・001

www.rohm.com

16.Dec.2015 Rev.001

BD37531FV

General Description

BD37531FV is a sound processor with built-in 3-band

equalizer for car audio.

A stereo input selector is

available that functions to switch single end input and

ground isolation input, input-gain control, main volume,

loudness and 5ch fader volume. Moreover, “Advanced

switch circuit”, which is an original ROHM technology,

can reduce various switching noise (ex. No-signal, low

frequency like 20Hz & large signal inputs). Also,

“Advanced switch” makes microcomputer control

easier and constructs a high quality car audio system.

Features



Reduced switching noise of input gain control,

mute, main volume, fader volume, bass, middle,

treble, loudness by using advanced switch circuit



Built-in differential input selector that can make

various combination of single-ended / differential

input.



Built-in ground isolation amplifier inputs, which is

ideal for external stereo input.



Built-in input gain controller reduces volume

switching noise of a portable audio input.



Decreased number of external components due to

built-in 3-band equalizer filter and loudness filter. It

is possible to freely control the Q, Gv, fo of the

3-band equalizer,

and Gv of the loudness



A gain adjustment quantity of ±20dB with a 1 dB

step gain adjustment is possible for the bass,

middle and treble.



Equipped with terminals for the subwoofer outputs.

Also, the audio signal outputs of the front, rear and

control.



Energy-saving design resulting in low current

consumption is achieved utilizing the BiCMOS

process. It has the advantage in quality over

scaling down the power heat control of the internal

regulators.



Input pins and output pins are organized and

separately laid out to keep the signal flow in one

direction which consequently, simplify pattern

layout of the set board and decrease the board

dimensions.



Key Specifications



Power Supply Voltage Range:

7.0V to 9.5V



Circuit Current (No signal) :

38mA(Typ)



Total Harmonic Distortion 1:

(FRONT,REAR)

0.001%(Typ)



Total Harmonic Distortion 2:

(SUBWOOFER)

0.002%(Typ)



Maximum Input voltage:

2.3Vrms (Typ)



Cross-talk Between Selectors:

-100dB (Typ)



Volume Control Range:

+15dB to -79dB



Output Noise Voltage 1:

(FRONT,REAR)

3.8µVrms(Typ)



Output Noise Voltage 2:

(SUBWOOFER)

4.8µVrms(Typ)



Residual Output Noise Voltage:

1.8µVrms(Typ)



Operating Temperature Range:

-40°C to +85°C

Package

W(Typ) x D(Typ) x H(Max)

Applications

It is optimal for car audio systems. It can also be used

for audio equipment of mini Compo, micro Compo, TV,

etc.

SSOP-B28

10.0mm x 7.60mm x 1.35mm

Datasheet

Datasheet