Datasheet
Sound Processor with Built-in 2-band Equalizer
BD37521FS
General Description
Key Specifications
BD37521FS is a sound processor with built-in 2-band
equalizer for car audio. Other features are stereo 4ch input
selector, input-gain control, main volume, loudness, and a
4ch fader volume. It is equipped with an “Advanced switch
circuit”, which is an original ROHM technology that
reduces various switching noise (ex. No-signal, low
frequency such as 20Hz & large signal inputs). Also, this
“Advanced switch” makes control of microcomputer easier
and can be used for designing high quality car audio
system.
Power Supply Voltage Range:
Circuit Current (No Signal):
TotalHarmonic Distortion:
Maximum Input Voltage:
Cross-talk Between Selectors:
Volume Control Range:
Output Noise Voltage:
Residual Output Noise Voltage:
Operating Temperature Range:
7.0V to 9.5V
38mA(Typ)
0.001%(Typ)
2.3Vrms (Typ)
-100dB (Typ)
+15dB to -79dB
3.8µVrms(Typ)
1.8µVrms (Typ)
-40°C to +85°C
Package
W(Typ) x D(Typ) x H(Max)
Features
Reduced switching noise of input gain control, mute,
main volume, fader volume, bass, treble, and
loudness by using advanced switch circuit.
Built-in 1 differential input selector and 3 single-ended
input selectors
Built-in ground isolation amplifier inputs which is ideal
for external stereo input.
Built-in input gain controller which reduces switching
noise for volume of a portable audio input.
Lesser number of external components due to built-in
2-band equalizer filter. This makes it possible to
control the Gv of 2-band equalizer and Gv of loudness
by I2C BUS.
SSOP-A24
10.00mm x 7.80mm x 2.10mm
A gain adjustment quantity of ±20dB with a 1 dB step
gain adjustment is possible for the bass and treble.
Energy-saving design resulting in low current
consumption is achieved by 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 that consequently simplify pattern layout of
the set board and decrease the board dimensions.
It is possible to be controlled by a 3.3V / 5V I2C BUS .
Applications
It is best suited for car audio applications. It is also suitable
for other audio equipment such as mini-component,
micro-component, television, etc.
○Product structure:Silicon monolithic integrated circuit ○This product has no designed protection against radioactive rays
www.rohm.com
TSZ02201-0C2C0E100460-1-2
16.Dec.2015 Rev.001
© 2015 ROHM Co., Ltd. All rights reserved.
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