BA3131FS Standard ICs Dual operational amplifier with switch, for audio use (3 inputs × 1 output × 2) BA3131FS The BA3131FS contains two built-in circuits with operational amplifiers configured of three differential input circuits, an output circuit, and a switch circuit. The three differential input circuits are separate, enabling independent settings to be entered for the gain and frequency characteristics. !Applications Car stereos, audio amplifiers and other electronic circuits !Features 1) High gain and low distortion. (Gv = 110dB, THD = 0.0015% typ.) 2) Low noise. (Vn = 2µVrms typ.) 3) Switching circuit can be directly coupled to microcomputer port. 4) Small switching noise. 5) Equipped with 1 / 2 Vcc output circuit for single power supply. !Block diagram + IN1A 1 - IN1A 2 20 + IN2A 19 - IN2A – + + IN1B 3 - IN1B 4 +– 18 + IN2B 17 - IN2B +– – + + IN1C 5 - IN1C 6 16 + IN2C 15 - IN2C +– – + OUT1 14 OUT2 7 3 SW1 3 13 Vref OUT 8 + SW2 – 12 1 / 2 VCC 9 GND 10 11 VCC R R BA3131FS Standard ICs !Absolute maximum ratings (Ta=25°C) Parameter Symbol Limits Power supply voltage VCC 18.0 V Power dissipation Pd 750∗ mW Operating temperature Topr – 40 ~ + 85 ˚C Storage temperature Tstg – 55 ~ + 125 ˚C Vi 3 ~ VCC V Common-mode input voltage Differential input voltage Vid VCC Load current IoMax. ± 50.0 Unit V mA ∗ Reduced by 7.5mW for each increase in Ta of 1˚C over 25˚C. (When mounted on a glass epoxy board (90mm × 50mm × 1.6t)) !Recommended operating conditions (Ta=25°C) Parameter Operating power supply voltage Symbol Min. Typ. Max. Unit Conditions 6.0 8.0 16.0 V single power source VCC !Electrical characteristics (unless otherwise noted, Ta=25°C, Vcc=8V) Parameter Min. Typ. Max. Unit Quiescent current Iq 2.0 4.9 7.8 mA VIN = 0, RL = ∞ , SW pin open Fig.2 Input offset voltage Vio - 0.5 5.0 mV RS ≤ 10kΩ Fig.1 Input offset current Iio - 5 200 nA Input bias current Ib - 50 500 nA ∗1 Fig.1 High-amplitude voltage gain Avol 86 110 - dB RL ≥ 2kΩ, VO = ± 1.5V Fig.1 Common-mode input voltage Vicm 3 6 - V In-phase signal rejection ratio CMRR 60 72 - dB RS ≤ 10kΩ Fig.1 Power supply voltage rejection ratio PSRR 76 90 - dB RS ≤ 10kΩ Fig.1 Maximum output voltage VOH / VOL 3 6 - V RL ≥ 10kΩ 3 6 - V RL ≥ 2kΩ Fig.3 / Fig.4 Input conversion noise voltage Vn - 2.0 4.0 µVrms ∗2 Fig.7 ∆VREF - - Reference voltage change ± 10 mV Conditions Measurement circuit Symbol Fig.1 Fig.1 Ioref = ± 1mA - ∗1 Because the first stage is contigured with PNP transistors, input bias current is from the IC. ∗2 Tested under the following conditions: GV = 40dB, RS = 2kΩ, Matsushita Tsuko VP-9690A (using DIN audio filter) !Design guaranteed values (unless otherwise noted, Ta=25°C, Vcc=8V) Parameter Min. Typ. Max. SR 0.5 1.2 - Gainbandwidth product GBW 1.5 2.6 - MHz f = 10kHz Fig.6 Crosstalk between A, B and C CTABC 60 73 - dB f = 1kHz Fig.8 Total harmonic distortion THD - % GV = 0dB, f = 1kHz, VO = 1Vrms Fig.9 CS 90 dB f = 1kHz, input conversion Fig.10 Slew rate Channel separation ∗ This item is not guaranteed during processes. 0.0025 0.01 115 - Unit Conditions Measurement circuit Symbol V / µS GV = 0dB, RL = 2kΩ Fig.5 BA3131FS Standard ICs !Measurement circuit C2 0.1µF RK 50kΩ RK 500kΩ C1 EK 0.1µF S1 VCC Rs Ri 50Ω 10kΩ VO 15V RK 500kΩ + – NULL DUT – VF + Rs Ri 50Ω 10kΩ S3 C3 1000pF S4 – 15V S2 Rf 50kΩ VR RL2 10kΩ RL1 2kΩ Vref Vref Vref ∗ C2 and C3 are used to prevent oscillation (adjustment required) Fig.1 BA3131FS Standard ICs !Measurement conditions (Figure 1) VCC VR EK VF S1 S2 Input offset voltage 8 Vref — VF1 ON ON OFF OFF 1 Input offset current 8 Vref — VF2 OFF OFF OFF OFF 2 VF3 OFF ON VF4 ON OFF ON Measurement Item Input bias current 8 Vref High-amplitude voltage gain 8 Vref Common-mode signal rejection ratio (Common-mode input voltage) 8 8 Power supply voltage rejection ratio — 5.5 VF5 2.5 VF6 6 8 VF7 2 0 VF8 6 Vref — VF9 18 Vref — VF10 !Equations (1) Input offset voltage (Vio) Vio = | VF1 | / (1 + Rf / Rs) (2) Input offset current (Iio) Iio = | VF2 - VF1 | / (Ri (1 + Rf / Rs) ) (3) Input bias current (Ib) Ib = | VF4 - VF3 | / (2 Ri (1 + Rf / Rs) ) (4) High-amplitude voltage gain (Avol) Avol = 20log (3 (1 + Rf / Rs) / | VF6 - VF5 | ) (dB) (5) In-phase signal rejection ratio (CMRR) CMRR = 20log (4 (1 + Rf / Rs) / | VF8 - VF7 | ) (dB) (6) (In-phase input voltage range) (PSRR) PSRR = 20log (12 (1 + Rf / Rs) / | VF10 - VF9 | ) (dB) S3 S4 Equation OFF OFF 3 ON ON OFF 4 ON ON OFF OFF 5 ON ON OFF OFF 6 BA3131FS Standard ICs !Measurement circuits Vcc Iq Vcc A + – + 2k or 10kΩ – 1V Vref Vref Vref V VoH Vref Fig. 3 Maximum output voltage: High Fig.2 Iq Vcc = 18V Vcc + – 1V Vref Vref 2k or 10kΩ – VOUT V VoL + VIN RL 2kΩ Vref Vref Fig. 4 Maximum output voltage: Low Fig. 5 Slew rate ( ) Vout (V) 15 Vcc t (µsec) 10kΩ 0.1µF – 10µF + V VIN f = 10kHz 5 t SR = 10 / t Fig. 6 Slew rate ( ) Vref GB = Vo / VIN × f Fig. 7 Band width frequency gain Vo BA3131FS Standard ICs 100kΩ – A 1kΩ / 100kΩ 1kΩ + 100kΩ Vcc 3.3µF 0.47µF B.P.F 20Hz ~ 30kHz + – 2.2kΩ 56kΩ Vref Von 1kΩ / 100kΩ Vref – B Vo + 100kΩ 1kΩ 100kΩ – C Vref Vref 100kΩ + 1kΩ CTABC = 20log 1kΩ / 100kΩ 1k Vn = 47µF Vcc = 8V Von 3 100 × 10 1÷ 1 × 103 Vref ~ VIN f = 1kHz Channel selection Vref Fig. 8 Input conversion noise voltage Vo Vcc 3.3µF 0.47µF + 56kΩ 100kΩ Distortion meter – 2.2kΩ VIN f = 1kHz Fig. 9 Crosstalk between A and B 100kΩ – Vo1 + ~ Vref 1kΩ CH-1 1kΩ Vref 1k / 100kΩ Vo = 1Vrms Vref Fig. 10 Total harmonic distortion 100kΩ 1kΩ – Vo2 + ~ Vref CH-2 f = 1kHz 1k / 100kΩ Vref CS = 20log Vo1 100Vo2 Vcc = 8V Fig. 12 Channel separation ( ) Vref Fig. 11 Channel separation ( ) VoA or VoB VoC BA3131FS Standard ICs !Application example R2 47k R8 1k R4 47k R10 1k R6 47k Aamp: Gv = 20dB Bamp: Gv = 10dB Camp: Gv = 0dB R12 1k 3.3µ IN2C C6 3.3µ IN2B C5 IN2A R16 3.3µ OUT2 10k R14 C4 3.3k Vcc = 8V 20 19 18 17 16 15 14 13 12 11 C7 BA3131FS 1 2 3 4 5 100µ 6 7 8 9 C9 C10 0.022µ 22µ C8 100µ 10 R13 3.3k 3.3µ R15 IN1A OUT1 C3 IN1B C2 IN1C 10k 3.3µ 3.3µ C1 R1 47k R7 1k R3 47k R9 1k R5 47k R11 1k SW1 SW2 µCOM. Fig.13 BA3131FS Standard ICs !Operation notes (1) Pin 13 is the reference output pin, from which 1 / 2 Vcc is output. The value for the bypass capacitor should be determined based on the desired characteristics. A value between 500pF and 1µF may produce oscillation, so if AC grounding is being used, always use a bypass capacitor with a value of at least 10µF. Also, Pin 12 is designated for reference circuit input, so if reference output is being used, always use a bypass capacitor for AC grounding. (We recommend a bypass capacitor with a value of 22µF.) •Reference data (these values are intended only as a reference, and performance is not guaranteed) Pin 12 bypass capacitor (µF) Ripple rejection ratio (fIN = 100 Hz) (dB) Output rise time (ms)∗ 10 – 35 150 22 – 42 300 47 – 48 550 ∗ Test conditions: When power supply is on (VCC = 8V), time equal to 90% of VCC bypass capacitor,Pin 13 bypass capacitor 100µF, output smoothing voltage. (2) This IC offers stability even at low gain (0 to 20dB), but a capacitance load of 200pF or higher may cause oscillation (the phase margin at a capacitance of 200pF is 10° typ. (Ta = 85°C, 0dB point) ). Consequently, please make sure sufficient care is taken in terms of the capacitance load. When using a 0dB buffer, as shown in the application example (Figure 13), introducing a bias resistance of several kΩ to the negative input (R11 and R12 in Figure 13, indicated as circled items) results in greater stability in terms of the capacitance load. !Truth value table ch1 ch2 ch3 OFF Conditions SW1 (8pin) H H L L SW2 (9pin) H L H L Corresponds to µCOM output ∗ “H” when the applied voltage at pins 8 and 9 is 2.0V or more, and “L” when it is 1.0V or less. BA3131FS Standard ICs !Electrical characteristic curves 120 1 Vcc = 8V Gv = 0dB Vo = 1Vrms 0.1 110 CTABC 0.05 0.01 90 C.S. 80 70 60 0.005 Vcc = 8V Gv = 0dB Vo = 1Vrms 50 0.00 20 50 100 500 1k 40 20 5k 10k 20k FREQUENCY: f (Hz) REFERENCE VOLTAGE :Vref (V) Vcc = 8V SINK 4.0 SOURCE 3.9 10 13pin OUTPUT CURRENT: ∆IOUT (mA) Fig. 17 Reference voltage vs. pin 13 output current !External dimensions (Units: mm) 1 10 5.4 ± 0.2 11 0.8 0.15 ± 0.1 1.8 ± 0.1 0.11 7.8 ± 0.3 8.7 ± 0.2 20 0.36 ± 0.1 5k 10k 20k Fig. 15 Channel separation and crosstalk vs. frequency 4.1 5 500 1k FREQUENCY: f (Hz) Fig. 14 Distortion vs. frequency 0 50 100 0.3Min. 0.15 SSOP-A20 DISTN (THD + Vn) (%) 0.1 VCC = 8V GV = 0dB 0.05 100 C.S., CTABC (dB) DISTN (THD + Vn) (%) 0.5 0.01 fIN = 10kHz 1kHz 100Hz 0.005 0.001 0.05 0.1 0.5 1.0 OUTPUT VOLTAGE: Vo (Vrms) Fig. 16 Distortion vs. output voltage