DatasheeDatasheett Sound Processor with Built-in 3-band Equalizer BD37531FV General Description Key Specifications BD37531FV is a sound processor with built-in 3-band Power Supply Voltage Range: 7.0V to 9.5V equalizer for car audio. A stereo input selector is Circuit Current (No signal) : 38mA(Typ) available that functions to switch single end input and Total Harmonic Distortion 1: ground isolation input, input-gain control, main volume, (FRONT,REAR) 0.001%(Typ) loudness and 5ch fader volume. Moreover, Advanced Total Harmonic Distortion 2: switch circuit, which is an original ROHM technology, (SUBWOOFER) 0.002%(Typ) can reduce various switching noise (ex. No-signal, low Maximum Input voltage: 2.3Vrms (Typ) frequency like 20Hz & large signal inputs). Also, Cross-talk Between Selectors: -100dB (Typ) Advanced switch makes microcomputer control Volume Control Range: +15dB to -79dB easier and constructs a high quality car audio system. Output Noise Voltage 1: (FRONT,REAR) 3.8Vrms(Typ) Output Noise Voltage 2: Features (SUBWOOFER) 4.8Vrms(Typ) Reduced switching noise of input gain control, Residual Output Noise Voltage: 1.8Vrms(Typ) mute, main volume, fader volume, bass, middle, Operating Temperature Range: -40C to +85C treble, loudness by using advanced switch circuit Built-in differential input selector that can make Package W(Typ) x D(Typ) x H(Max) 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 2 through the I C BUS control A gain adjustment quantity of 20dB with a 1 dB step gain adjustment is possible for the bass, SSOP-B28 middle and treble. 10.0mm x 7.60mm x 1.35mm Equipped with terminals for the subwoofer outputs. Also, the audio signal outputs of the front, rear and 2 subwoofer can be chosen using the I C BUS control. Energy-saving design resulting in low current consumption is achieved utilizing the BiCMOS Applications process. It has the advantage in quality over It is optimal for car audio systems. It can also be used scaling down the power heat control of the internal for audio equipment of mini Compo, micro Compo, TV, regulators. etc. 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. 2 It is possible to control I C BUS with 3.3V / 5V. Product structureSilicon monolithic integrated circuit This product has no designed protection against radioactive rays www.rohm.com TSZ02201-0C2C0E100520-1-2 2015 ROHM Co., Ltd. All rights reserved. 1/30 16.Dec.2015 Rev.001 TSZ2211114001 BD37531FV Typical Application Circuit BD37531FV Pin Configuration TOP VIEW A1 1 28 FIL A2 2 27 GND B1 3 26 SDA B2 4 25 SCL C1 5 24 VCC C2 6 23 OUTF1 22 OUTF2 DP1 7 DN 8 21 OUTR1 DP2 9 20 OUTR2 EP1 10 19 OUTS1 EN1 11 18 OUTS2 EN2 12 17 TEST3 EP2 13 16 TEST2 TEST1 14 15 MUTE Pin Descriptions Pin Pin No. Pin Name Description Pin No. Description Name 1 A1 A input terminal of 1ch 15 MUTE External compulsory mute terminal 2 A2 A input terminal of 2ch 16 TEST2 Test Pin 3 B1 B input terminal of 1ch 17 TEST3 Test Pin 4 B2 B input terminal of 2ch 18 OUTS2 Subwoofer output terminal of 2ch 5 C1 C input terminal of 1ch 19 OUTS1 Subwoofer output terminal of 1ch 6 C2 C input terminal of 2ch 20 OUTR2 Rear output terminal of 2ch 7 DP1 D positive input terminal of 1ch 21 OUTR1 Rear output terminal of 1ch 8 DN D negative input terminal 22 OUTF2 Front output terminal of 2ch 9 DP2 D positive input terminal of 2ch 23 OUTF1 Front output terminal of 1ch 10 EP1 E positive input terminal of 1ch 24 VCC Power supply terminal 2 11 EN1 E negative input terminal of 1ch 25 SCL I C Communication clock terminal 2 12 EN2 E negative input terminal of 2ch 26 SDA I C Communication data terminal 13 EP2 E positive input terminal of 2ch 27 GND GND terminal 14 TEST1 Test Pin 28 FIL VCC/2 terminal www.rohm.com TSZ02201-0C2C0E100520-1-2 2015 ROHM Co., Ltd. All rights reserved. 2/30 TSZ2211115001 16.Dec.2015 Rev.001