Sound Processors for BOOM BOX / Mini-component Stereo Sound Processors with Built-in 2-band Equalizers BD3870FS,BD3871FS,BD3872FS,BD3873FS No.10086EAT02 ●Description The Sound Processor with built-in 2 Band Equalizer, incorporates functions required for BOOM BOX and mini-component systems, such as input selector, input gain amp, volume, surround, tone (bass, treble), and loud speaker equalizer (BD3872FS only). These functions can be controlled through the two-wire serial control. ●Features 1) Using external components, center frequencies and Q factors of the bass characteristics are flexible. 2) Providing a mute switch onto one of the input pins allows cross-talk suppression. 3) A surround function can be constructed without external components. 4) Energy-saving design resulting in low current consumption, by utilizing the BiCMOS process ●Applications BOOM BOX, mini-audio systems, and micro-audio systems. ●Line up matrix Parameter Input Gain BD3870FS BD3871FS BD3873FS BD3872FS 0, 6, 12, 18dB 24, 26, 28dB 18, 21, 24, 27dB 0, 5, 10, 19, 21, 23, 26, 28dB No No No Yes Three inputs Three inputs Three inputs Five inputs 0 to -87dB/ 1dB step, -dB 2 band (Bass, Treble) 0 to -87dB/ 1dB step, -dB 2 band (Bass, Treble) 0 to –87dB/ 1dB step, -dB 2 band (Bass, Treble) 0 to -87dB/ 1dB step, -dB 2 band (Bass, Treble) Yes Yes Yes Yes Two-wire serial Two-wire serial Two-wire serial Two-wire serial SSOP-A24 SSOP-A24 SSOP-A24 SSOP-A32 Loud Speaker Equalizer (SEQ) Input Selector Volume Equalizer Surround Serial Control Package ●Absolute maximum ratings (Ta=25℃) Prameter Symbol Ratings BD3870FS BD3871FS BD3873FS BD3872FS Unit Power Supply Voltage Vcc 10 10 10 10 V Power Dissipation Pd 800 *1 800 *1 800 *1 950 *2 mW Operating Temperature Range Topr -25 to +75 -25 to +75 -25 to +75 -25 to +75 ℃ Storage Temperature Range Tstg -55 to +125 -55 to +125 -55 to +125 -55 to +125 ℃ *1 Reduced by 8.0 mW/℃ at 25℃ or higher, when installed on the standard board (Size: 70×70×1.6mm). *2 Reduced by 9.5 mW/℃ at 25℃ or higher, when installed on the standard board (Size: 70×70×1.6mm). ●Operating voltage range Prameter Operating Voltage Range Symbol Vcc Ratings BD3870FS BD3871FS BD3873FS BD3872FS 4.5 to 9.5 4.5 to 9.5 4.5 to 9.5 4.5 to 9.5 Unit V *It must function normally at Ta=25℃. www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 1/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS Block ●Electrical characteristics (Ta=25 ℃ , VCC=8V, f=1kHz, Vi=200mVrms, RL=10kΩ, Rg=600Ω, Input Gain=0dB (BD3870FS, BD3872FS only), Input Gain=24dB (BD3871FS only), Input Gain=18dB (BD3873FS only),Volume=0dB, Bass=0dB, Treble=0dB, Surround=OFF, Loud Speaker Equalizer=OFF (BD3872FS only), unless otherwise noted) Parameter Circuit Current Bass Volume Total Total Output Voltage Gain Treble Surround IQ Gv Limits Min. Typ. Max. - 8 21 -2 0 2 22 24 26 16 18 20 Unit At no signal dB BD3870FS, BD3872FS Gv=20log(VOUT/VIN) BD3871FS Gv=20log(VOUT/VIN) BD3873FS Gv=20log(VOUT/VIN) BW=400 to 30kHz THD - 0.01 0.1 % Maximum Output Voltage Vom 1.6 2.1 - Vrms - 4.5 15 Total Output Noise Voltage Vno - 40 80 µVrms Total Residual Noise Voltage Vmno - 4.5 15 µVrms Cross-talk between Channels CTC - -80 -70 dB Cross-talk between Selectors CTS - -80 -70 dB 35 50 65 Input Impedance Rin 70 100 130 Condition mA Total Harmonic Distortion ratio THD=1% BW=400 to 30kHz BD3870FS, BD3872FS Rg=0Ω, BW=IHF-A BD3871FS, BD3873FS Rg=0Ω, BW=IHF-A Rg=0Ω, BW=IHF-A Volume=-dB Rg=0Ω, BW=IHF-A VOUT=1Vrms Rg=0Ω, BW=IHF-A BD3870FS, BD3871FS, BD3873FS kΩ BD3872FS Output Impedance Rout - - 50 Ω Volume Control Range VRI -90 -87 -84 dB VR=20log(VOUT/VIN) Maximum Volume Attenuation Vmin - - -90 dB BW=IHF-A Volume Input Impedance Rvin 39 56 73 kΩ Bass Boost Gain GBB 12 14 16 dB GB=20log(VOUT/VIN) Bass Cut Gain GBC -16 -14 -12 dB GB=20log(VOUT/VIN) BR - 2 - dB 10 12 14 Bass Step Resolution SEQ Symbol Treble Boost Gain GTB Treble Cut Gain GTC 12 14 16 -14 -12 -10 -16 -14 -12 BD3870FS, BD3871FS, BD3873FS dB BD3872FS BD3870FS, BD3871FS, BD3873FS dB BD3872FS Treble Step Resolution TR - 2 - dB Surround In-phase Gain Vsur1 -2 0 2 dB 2ch in-phase inputs Surround Single-phase Gain Vsur2 4.3 6.3 8.3 dB 1ch input, 1ch grounded Surround Opposite-phase Gain Vsur3 8 10 12 dB 2ch opposite-phase inputs Seq 3 5 7 dB f=10kHz Loud Speaker Equalizer Gain (BD3872FS only) * For measurement, VP-9690A (Average value wave detection, Effective value display) IHF-A filter by Matsushita Communication Industrial is used. * Phase relation between Input/Output signal terminals is the same. * Note: This IC is not designed to be radiation-resistant. www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 2/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS ●Timing chart 1) Signal Timing Conditions ・Data is read on the rising edge of the clock. ・Latch is read out on the falling edge of the clock. ・Latch signal must end with the LOW state. ・To avoid malfunctions, clock and data signals must terminate with the LOW state. 1byte=10bit SC (CLOCK) 90% tsu 90% twc 10% thd SI DATA LATCH 90% twd ts th 90% DATA 90% 90% 10% 10% twc tsd ts1 90% twh th1 90% DATA 10% 10% thd 10% LATCH End with Low Fig.1 Parameter Symbol 90% tw1 Limits Min. Typ. Max. Unit Minimum Clock Width Twc 2.0 - - µs Minimum Data Width twd 2.0 - - µs Minimum Latch Width Tw1 2.0 - - µs Data Set-up Time (DATACLK) Tsd 1.0 - - µs Data Hold Time (CLKDATA) Thd 1.0 - - µs Latch Set-up Time (CLKLATCH) Ts1 1.0 - - µs Latch Hold Time (DATALATCH) Th1 1.0 - - µs Latch Low Set-up Time Ts 1.0 - - µs Latch Low Hold Width Twh 2.0 - - µs 2) Voltage Conditions for Control Signals Limits Parameter Min. Typ. Max. (≦Vcc) Unit “H” Input Voltage 2.2 - 5.5 V Vcc=4.5 to 9.5V “L” Input Voltage 0 - 1.0 V Vcc=4.5 to 9.5V www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 3/15 Condition 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS 3) Control Data Format List Basic Configuration of Control Data Format Data input direction MSB D9 D8 D7 LSB D6 D5 D4 D3 D2 D1 Select Address Data Control Data Format (BD3870FS, BD3871FS, BD3873FS) Data input direction D9 D8 D7 D6 D5 (1) Input Selector Input Gain (2) Surround D4 D3 D2 D1 D0 * * * 0 0 * 0 1 1 0 Volume A (3) Volume B Bass Gain (4) * * Control Data Format (BD3872FS) Data input direction D9 D8 (1) Treble Gain * * * * * * 1 1 D7 D6 D5 D4 D3 D2 D1 D0 * * 0 0 * 0 1 1 0 1 1 Input Gain (2) Input Selector Volume A (3) Volume B Bass Gain (4) * * D0 * Treble Gain * * * Surround SEQ ・”*” indicates 0 or 1. ・By changing the setting of Select Address, three or four different control formats (BD3871FS, BD3872FS, BD3873FS, plus BD3872FS) are selectable. ・In every power-on sequence, all of the address data must be initialized. Example: ←Input direction MSB Data(1) LSB MSB L Data(2) LSB L MSB Data(3) LSB L MSB Data(4) LSB L “L” indicates a latch. ・After power-on, for the second and subsequent times, only the necessary data can be selected for setting. Example: When changing the volume, ←Input direction MSB Data(2) LSB L “L” indicates a latch. www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 4/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS ●Block diagram, application circuit, pin assignment (BD3870FS, BD3871FS, BD3873FS) 5.6k 5.6k 0.1μ 0.1μ 0.1μ 0.1μ OUT1 OUT2 0.33μ 0.0022μ 0.0022μ 10μ 390k 24 Surround 23 22 Treble1 fc=8k Hz Treble２ fc=8kHz 21 DATA VCC LATCH CLOCK 10μ 390k 20 19 Bass2 f0 =80Hz 18 17 16 15 14 13 Logic Bass1 f0=80Hz Vcc/2 Vcc/2 0dB ～ -87dB -∞ Vcc/2 Vcc/2 Vcc/2 1 2 50k 3 4 5 50k 50k 6 7 50k 50k 8 50k 9 10 11 12 47μ 10μ 10μ A1 10μ 10μ A2 B1 10μ 10μ 10μ 4.7k B2 4.7k 10μ C1 C2 Unit: Resistance =Ω, Capacitor = F Fig.2 ●Pin description (BD3870FS, BD3871FS, BD3873FS) Pin No. Pin Name Description Pin No. Pin Name Description 1 VIN1 1ch volume input pin 13 SC Serial clock input pin 2 VIN2 2ch volume input pin 14 SI Serial data input pin 3 SEL2 2ch input selector output pin 15 VCC Power supply pin 4 SEL1 1ch input selector output pin 16 OUT2 2ch output pin 5 A1 1ch input pin A 17 OUT1 1ch output pin 6 A2 2ch input pin A 18 BOUT1 1ch bass filter setting pin 7 B1 1ch input pin B 19 BNF1 1ch bass filter setting pin 8 B2 2ch input pin B 20 BOUT2 2ch bass filter setting pin 9 C1 1ch input pin C 21 BNF2 2ch bass filter setting pin 10 C2 2ch input pin C 22 TNF2 2ch treble filter setting pin 11 FILTER 1/2 VCC pin 23 TNF1 1ch treble filter setting pin 12 GND Ground pin 24 CAP Time constant setting pin for absorbing surround switching shock sound www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 5/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS ●Block diagram, application circuit, pin assignment (BD3872FS) OUT1 0.001μ 0.022μ Vcc/2 32 31 Loud speaker equalizer2 5.6K 0.1μ 4.7μ 4.7μ 27 26 Treble1 fc=10kHz Treble2 fc=10kHz DATA CLOCK LATCH 0.33μ + 390K 390K 28 29 0.1μ + Vcc/2 30 5.6K 0.1μ 25 24 Bass1 f 0=80Hz 23 22 21 20 19 18 17 Logic Bass2 f0 =80Hz Surround Loud speaker 0.0022μ 0.0022μ 0.1μ 0.001μ 62K Vcc OUT2 Vcc/2 Vcc/2 Vcc/2 0dB ～ -87dB -∞ 0dB ～ -87dB -∞ Vcc/2 Vcc/2 100k 1 2 3 4 100k 5 6 100k 100k 8 7 100k 9 100k 10 100k 100k 12 11 100k 13 100k 14 15 16 + 0.1μ 0.22μ 0.1μ 0.1μ 0.1μ 0.1μ 0.1μ 0.1μ 0.1μ 0.22μ A1 A2 B1 B2 C1 C2 D1 D2 E1 0.1μ 0.1μ 4.7k 4.7k 10μ E2 Unit: Resistance =Ω, Capacitor = F Fig.3 Application to Cinema Surround www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 6/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS OUT1 OUT2 0.33μ 0.01μ 0.33μ 0.01μ 0.0022μ 0.0022μ 0.1μ 5.6K 0.1μ 0.1μ 5.6K 0.1μ 4.7μ + 32 31 29 Loud speaker equalizer2 28 27 Treble1 fc=10kHz Treble２ fc=10kHz Bass1 f0 =80Hz 390K 23 24 4.7μ DATA CLOCK LATCH 0.33μ + 22 21 20 19 18 17 Logic Bass2 f0 =80Hz Surround Loud speaker equalizer1 30 390K 26 25 Vcc Vcc/2 Vcc/2 Vcc/2 0dB ～ -87dB -∞ 0dB ～ -87dB -∞ Vcc/2 Vcc/2 100k 1 2 3 4 5 100k 6 100k 100k 8 7 100k 9 100k 10 100k 11 100k 12 100k 13 100k 14 15 16 + 0.1μ 0.22μ 0.1μ 0.1μ 0.1μ 0.1μ 0.1μ 0.1μ 0.1μ 0.22μ A1 A2 B1 B2 C1 C2 D1 D2 E1 0.1μ 0.1μ 4.7k 4.7k 10μ E2 Unit: Resistance =Ω, Capacitor = F Fig.4 Application to Loud Speaker Equalizer www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 7/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS ●Pin description (BD3872FS) Pin No. Pin Name Description Pin No. Pin Name Description 1 VIN1 1ch volume input pin 17 SC Serial clock input pin 2 SEL1 1ch input selector output pin 18 SI Serial data input pin 3 VIN2 2ch volume input pin 19 VCC Power supply pin 4 SEL2 2ch input selector output pin 20 CAP Time constant setting pin for absorbing switching shock sound 5 A1 1ch input pin A 21 OUT2 2ch output pin 6 A2 2ch input pin A 22 OUT1 1ch output pin 7 B1 1ch input pin B 23 BOUT2 2ch bass filter setting pin 8 B2 2ch input pin B 24 BNF2 2ch bass filter setting pin 9 C1 1ch input pin C 25 BOUT1 1ch bass filter setting pin 10 C2 2ch input pin C 26 BNF1 1ch bass filter setting pin 11 D1 1ch input pin D 27 TNF2 2ch treble filter setting pin 12 D2 2ch input pin D 28 TNF1 1ch treble filter setting pin 13 E1 1ch input pin E 29 SOUT2 2ch cinema surround or SEQ setting pin 14 E2 2ch input pin E 30 SQI2 2ch cinema surround or SEQ setting pin 15 FILTER 1/2 VCC pin 31 SOUT1 1ch cinema surround or SEQ setting pin 16 GND Ground pin 32 SQI1 1ch cinema surround or SEQ setting pin www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 8/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS ●Description of operations 1) Bass filter Using external components, center frequencies and Q factors of the bass characteristics are flexible 1 f0 (Hz) R1R2R3 R4 C1C2 2π IN R2 R3 R4 + R3 R1R2R4C1C2 R4 Q R2 R3 R4 R1C1 C2 R2 C1 R2 R3 R4 C2 R1 G(boost) 20log R1R2 R3 R4 R2R3 R1R2 R3 R4 Fig.5 R2R3 R1R2 R3 R4 Gٛcut ٛ 20log R2(R3 R4 ٛ R1R2 R3 R4 Standard values of R3, R4 (reference) (R1=5.6kΩ, R2=390kΩ, C1=C2=0.1µF) Resistance (kΩ) * Typ. Bass Boost Cut Amount R3 R4 0dB 77.64 0 2dB 58.90 18.73 4dB 44.02 33.60 6dB 32.20 45.42 8dB 22.82 54.80 10dB 15.36 62.26 12dB 9.44 68.18 14dB 4.78 72.84 C2 C1 C2 C1 C2 C1 C2 C1 1 (dB) 1 1 ٛ(dB) 1 G G f F0 G * The actual boost cut amount may deviate from the standard values in some degree. Fig.6 www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 9/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS 2) Treble filter IN OUT + fc = - 1 (Hz) 2πR2C G (boost) = 20log R1 R2 G (cut) = 20log Zc = 1 jωc R1+R2+Zc (dB) R2+Zc R2+Zc (dB) R1+R2+Zc (Ω) C Fig.7 G Standard values of R1, R2 (reference) Resistance (kΩ) * Typ. Treble Boost Cut Amount R1 R2 0dB 0 36.28 2dB 7.46 28.82 4dB 13.39 22.89 6dB 18.10 18.18 8dB 21.84 14.44 10dB 24.81 11.47 12dB 27.20 14dB (BD3872FS only) 29.04 9.08 7.24 3dB G G 3dB Fig.8 * The actual boost cut amount may deviate from the standard values in some degree. 3) Matrix surround f fc IN1 + L OUT1 + + (4.14L/2 - 2.14R/2) × 1/2 + + - × 2.14 × 1/2 R IN2 Fig.9 + + - (4.14R/2 - 2.14L/2) OUT2 Matrix surround is constructed as shown above. Gains are defined as follows: In-phase Gain: Gains obtained on OUT1 and OUT2 against IN1 when inputting a signal of the equivalent level and in-phase (L=R) to IN1 and IN2. OUT1 OUT2 4.14 2.14 20log1 0 (dB) L L L 1 2 IN1 IN2 2 Single-phase Gain: Gains obtained on OUT1 and OUT2 against IN1 when inputting a signal to IN1 and AC-grounding IN2 (R=0). OUT1 4.14 L L 2,07 20log2.07 6.3 (dB) IN1 2 OUT2 2.14 20log 1.07 0.59 (dB) L L 1.07 IN1 2 Opposite-phase Gain: Gains obtained on OUT1 and OUT2 against IN1 when inputting signals of the equivalent level and opposite-phase (L-R) to IN1 and IN2. OUT1 OUT2 4.14 2.14 20log3.14 10 (dB) L L L 3.14 IN1 IN2 2 2 www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 10/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS 1) Sound generation using Loud Speaker Equalizer (BD3872FS) Using external components, one of the following two functions can be established; one having an effect to localize the vocal forward and enhance it (Loud Speaker Equalizer) and the other having an effect to clarify the vocal quality and improve the Articulation Index (Cinema Surround). Those characteristic values can be adjusted by choosing the external components with desirable constants. Details of above two functions are described below: ◎Cinema Surround Constructing the external components as shown below allows the vocals to be moved forward and enhanced. Surround effect with enhanced vocal is achieved by turning on the built-in surround simultaneously. Merging this effect, while playing movies on a DVD player, will make vocal listening clearer and surround effect more impactful. 32 31 Loud speaker equalizer1 30 29 Loud speaker equalizer2 Fig.10 ◎Loud Speaker Equalizer (SEQ) BOOM BOX and Micro-sound systems are often restricted to using small-diameter speakers because of location space. These speakers, where the vocal range are attenuated, may give an impression of having a muffled vocal sound with respect to its audibility. Using the Loud Speaker Equalizer, the vocal quality which degrades in small-diameter speakers, can be improved and the Articulation Index is also increased. IN OUT Phase Shifter HPF SOUT (29. 31pin) SEQ (30, 32pin) C2 C1 Fig.11 ・C1 can be selected to determine the frequency where the phase should be inverted. C1 Frequency where the phase is inverted Larger value Set to the lower frequency side Smaller value Set to the higher frequency side ・C2 can be selected to determine the HPF cut-off frequency fc. The SEQ gain remains constant. 1 2RC (Hz) GAIN fc = (Where R is a built-in resistance of 10kΩ) 3dB Fc G=5dB (Constant) FREQUENCY Fig.12 www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 11/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS ●Reference data ICC (mA) 8 6 4 2 2 4 6 8 10 1 1 0.1 10 0.01 0.1 1 10 0.001 0.001 0.01 10 Fig.15 Total Harmonic Distortion ratio - Input Voltage (BD3870FS) 30 15 +14dB At 24dB setting 12 25 10 20 5 GAIN (dB) GAIN (dB) 18 14 1 Fig.14 Output Voltage - Input Voltage (BD3870FS) At 18dB setting 16 0.1 INPUT VOLTAGE (Vrms) 20 GAIN (dB) 0.01 INPUT VOLTAGE (Vrms) VCC (V) Fig.13 Circuit Current - Power Supply Voltage 0.1 0.01 0.001 0.001 0 0 10 THD+N (%) OUTPUT VOLTAGE (Vrms) 10 15 10 5 -14～+14dB 2dB step 0 -5 -10 -14dB 0 10 10 100 1000 10000 -15 10 100000 Fig.16 Current Gain - Frequency (BD3870FS, BD3873FS) 10000 100000 10 15 +12dB 100 1000 10000 100000 FREQUENCY (Hz) Fig.17 Voltage Gain - Frequency (BD3871FS) 10 Fig.18 Bass Gain - Frequency 20 +14dB 10 5 0 -5 15 -14～+14dB 5 GAIN (dB) -12～+12dB 2dB step GAIN (dB) GAIN (dB) 1000 FREQUENCY (Hz) FREQUENCY (Hz) 15 100 2dB step 0 -5 At oppoite-phase input 10 5 -10 -10 -12dB -15 10 100 1000 10000 100000 FREQUENCY (Hz) -14dB -15 10 100 1000 10000 0 100000 FREQUENCY (Hz) Fig.19 Treble Gain - Frequency (BD3870FS,BD3871FS,BD3873FS) Fig.20 Treble Gain - Frequency (BD3872FS) 10 100 1000 10000 100000 FREQUENCY (Hz) Fig.21 Surround Gain - Frequency 10 GAIN (dB) 8 6 4 2 0 10 100 1000 10000 100000 FREQUENCY (Hz) Fig. 22 Treble Gain - Frequency (BD3872FS) www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 12/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS ●Notes for use 1) Numbers and data in entries are representative design values and are not guaranteed values of the items. 2) Although ROHM is confident that the example application circuit reflects the best possible recommendations, be sure to verify circuit characteristics for your particular application. Modification of constants for other externally connected circuits may cause variations in both static and transient characteristics for external components as well as this Rohm IC. Allow for sufficient margins when determining circuit constants. 3) Absolute maximum ratings Use of the IC in excess of absolute maximum ratings, such as the applied voltage or operating temperature range (Topr), may result in IC damage. Assumptions should not be made regarding the state of the IC (short mode or open mode) when such damage is suffered. A physical safety measure, such as a fuse, should be implemented when using the IC at times where the absolute maximum ratings may be exceeded. 4) GND potential Ensure a minimum GND pin potential in all operating conditions. Make sure that no pins are at a voltage below the GND at any time, regardless of whether it is a transient signal or not. 5) Thermal design Perform thermal design, in which there are adequate margins, by taking into account the permissible dissipation (Pd) in actual states of use. 6) Short circuit between terminals and erroneous mounting Pay attention to the assembly direction of the ICs. Wrong mounting direction or shorts between terminals, GND, or other components on the circuits, can damage the IC. 7) Operation in strong electromagnetic field Using the ICs in a strong electromagnetic field can cause operation malfunction. 8) Power-ON RESET A built-in circuit for performing initialization inside the IC at power-ON is provided. In unstable systems it is recommended that the data shall be sent to all the addresses during power-ON, until this operation cycle is completed. Mute should be applied during this cycle. Function Initial Condition Input A Input Selector 0dB Input Gain Loud Speaker Equalizer OFF (BD3872FS only) Volume -dB Surround OFF Treble Gain 0dB Bass Gain 0dB 9) 2-wire serial control For the CL and DA terminals, the patterned and other wirings should be routed as not to cause interference with the analog-signal-related lines. 10) Switching between functions Shock sound is absorbed when switching between the volume, bass, and treble functions. 11) Input coupling capacitor As described in the figure below, low frequency characteristics are determined depending on the external capacitor value for input coupling, and the input impedance value inside the IC. G C 0 A (f) R f (2πfCR) A(f) = Fig.23 www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 2 1+(2πfCR)2 Fig.24 13/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS 12) Switching noise For Surround and Loud Speaker Equalizer (BD3872FS only), external capacitor C is attached to the CAP pin as a measures to control the switching noise. In the application circuit, a constant value as an example, is indicated by the CAP pin. The time constant, which is used to charge/discharge the external capacitor C (varying between Vbe to 5Vbe (2.65V)) on the CAP pin, controls the soft switching operation. The switching time constant T is stated as T=2.55×105×C. Vbe has a temperature characteristic and may affect the time constant T. 13) Input Selector and Input Gain When setting/changing Input Selector or Input Gain, the soft switching operation does not function and therefore noise is not controlled. For this reason, it is recommended to provide a mute circuit constructed of the external components for the set design. MUTE setting example MUTE (L=ON, H=OFF) SERIAL DATA SERIAL DATA 500～600ms 40～60ms INPUT SOURCE Fig.25 ●Thermal Derating Curve 1200 SSOP-A32 Power Dissipation : Pd （mW) 1000 SSOP-A24 800 600 400 200 0 0 25 50 75 100 125 Ambient Temperature: Ta(℃) When installed ROHM standard board (70×70×1.6mm Glass epoxy board) Fig.26 www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 14/15 2010.10 - Rev.A Technical Note BD3870FS,BD3871FS,BD3872FS,BD3873FS ●Ordering part number B D 3 Part No. 8 7 0 F Part No. 3870,3871,3873 3872 S - Package FS: SSOP-A24 SSOP-A32 E 2 Packaging and forming specification E2: Embossed tape and reel SSOP-A24 10 ± 0.2 (MAX 10.35 include BURR) 0.5±0.2 12 Tape Embossed carrier tape Quantity 2000pcs 0.1±0.1 0.8 0.1 Direction of feed E2 The direction is the 1pin of product is at the upper left when you hold ( reel on the left hand and you pull out the tape on the right hand ) +0.1 0.17 −0.05 1.8±0.1 1 1.2±0.15 7.8±0.3 <Tape and Reel information> 13 5.4±0.2 24 +6° 4° −4° 1pin 0.38±0.1 Reel (Unit : mm) Direction of feed ∗ Order quantity needs to be multiple of the minimum quantity. SSOP-A32 <Tape and Reel information> 13.6 ± 0.2 (MAX 13.95 include BURR) 17 Tape Embossed carrier tape Quantity 2000pcs Direction of feed 0.3MIN 5.4±0.2 7.8±0.3 32 1 E2 The direction is the 1pin of product is at the upper left when you hold ( reel on the left hand and you pull out the tape on the right hand ) 16 0.11 1.8±0.1 0.15 ± 0.1 0.36 ± 0.1 0.1 0.8 1pin Reel (Unit : mm) www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 15/15 Direction of feed ∗ Order quantity needs to be multiple of the minimum quantity. 2010.10 - Rev.A Notice Notes No copying or reproduction of this document, in part or in whole, is permitted without the consent of ROHM Co.,Ltd. The content specified herein is subject to change for improvement without notice. The content specified herein is for the purpose of introducing ROHM's products (hereinafter "Products"). If you wish to use any such Product, please be sure to refer to the specifications, which can be obtained from ROHM upon request. Examples of application circuits, circuit constants and any other information contained herein illustrate the standard usage and operations of the Products. The peripheral conditions must be taken into account when designing circuits for mass production. Great care was taken in ensuring the accuracy of the information specified in this document. However, should you incur any damage arising from any inaccuracy or misprint of such information, ROHM shall bear no responsibility for such damage. The technical information specified herein is intended only to show the typical functions of and examples of application circuits for the Products. ROHM does not grant you, explicitly or implicitly, any license to use or exercise intellectual property or other rights held by ROHM and other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the use of such technical information. The Products specified in this document are intended to be used with general-use electronic equipment or devices (such as audio visual equipment, office-automation equipment, communication devices, electronic appliances and amusement devices). The Products specified in this document are not designed to be radiation tolerant. While ROHM always makes efforts to enhance the quality and reliability of its Products, a Product may fail or malfunction for a variety of reasons. Please be sure to implement in your equipment using the Products safety measures to guard against the possibility of physical injury, fire or any other damage caused in the event of the failure of any Product, such as derating, redundancy, fire control and fail-safe designs. ROHM shall bear no responsibility whatsoever for your use of any Product outside of the prescribed scope or not in accordance with the instruction manual. The Products are not designed or manufactured to be used with any equipment, device or system which requires an extremely high level of reliability the failure or malfunction of which may result in a direct threat to human life or create a risk of human injury (such as a medical instrument, transportation equipment, aerospace machinery, nuclear-reactor controller, fuelcontroller or other safety device). ROHM shall bear no responsibility in any way for use of any of the Products for the above special purposes. If a Product is intended to be used for any such special purpose, please contact a ROHM sales representative before purchasing. If you intend to export or ship overseas any Product or technology specified herein that may be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to obtain a license or permit under the Law. Thank you for your accessing to ROHM product informations. More detail product informations and catalogs are available, please contact us. ROHM Customer Support System http://www.rohm.com/contact/ www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. R1010A