BA3870 Rohm, BA3870 Datasheet
BA3870
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BA3870 Summary of contents
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... BA3870 The BA3870 is a bass boost audio IC for radio cassette players. BBS adjusts the base boost to a level appropriate for the volume, achieving a rich sound without distortion. Frequency characteristics can be set externally, enabling system design to meet the needs of the application. ...
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... Audio ICs FBlock diagram BA3870 421 ...
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... Audio ICs FPin descriptions 422 BA3870 ...
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... Audio ICs FInput / output circuits FElectrical characteristics (unless otherwise noted 25_C 5.0V and f = 1kHz) CC BA3870 423 ...
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... Audio ICs FMeasurement circuit 424 BA3870 ...
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... It also adjusts the gain of the high-frequency range to attain a balanced sound with natural volume. (2) Operation of BBS (1) BBS on The signal system when BBS shown in Fig. 2. BA3870 425 ...
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... Gain of Amp 426 Here CL1 and the total frequency shows a *12dB / OCT bass 1 (Hz) boost as indicated in Fig // Also (dB) LP1 ) LP1 (dB) and thus the total gain during EVR Max Max. EVR G (dB) L Max. ) (dB (Hz (Hz (dB (dB and thus CL2 = (dB LP1 (dB) B BA3870 ...
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... The total frequency characteristics show a +6dB / OCT ) treble boost as shown in Fig Also, R (Hz and the total gain G (dB (dB) The total gain // (dB BA3870 = 2R , thus 10 = +9.5 (dB) in the frequency range is H1 CH1 = 9.5 (dB) HP1 t f frequency range is in the f H2 CH2 = HP2 9.5 (dB) HP2 427 ...
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... Audio ICs 428 BA3870 ...
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... DC voltage at BIAS OUT pin B If the volume output level at the beginning of control of the low range signal system ATT1 is V (dB) V BBS In this way, bass boost control is carried out based on the volume as shown in Fig. 9. (dBV BA3870 (dBV), BBS + ATT2 E COM 429 ...
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... Fig. 11, and the gains are given by the following equa- tions: Attenuation of ATT3 20log ATT3 R 21 Gain of Amp D’: G ’ = 20log and the total gain off ’ OFF ATT3 (dB) OFF and the characteristics are flat as shown in Fig. 12 430 R 20 (dB (dB when BBS OFF BA3870 ...
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... Audio ICs FApplication examples BA3870 431 ...
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... LP NF pin, however, feedback will increase causing greater susceptibility to oscillation. We recom- mend a gain G of 12dB or more. B (5) Coupling capacitors Decide the polarity of the input and output coupling ca- pacitors based on the electrical potentials of the devices to which they are being connected. BA3870 ...
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... Audio ICs FElectrical characteristic curves FExternal dimensions (Units: mm) BA3870 433 ...