FA7611

FA7611CP(E) FA7611CP(E) s Description The FA7611CP(E) is a bipolar IC containing basic circuit necessary for PWM-type switching power supply control. Bipolar IC For Switching Power Supply Control s Dimensions, mm SSOP-16 16 9 s Features • Low-voltage operation (VCC = 3.6 to 22V) • Predrivers: Totem-pole output or open-collector for CH1 and open-collector output for CH2 • Latch-mode short-circuit protection function (no malfunction due to electrical noise) • soft-start function • Undervoltage lock-out function • One capacitor shared for short circuit protection and for soft start to minimize the number of external discrete components 5.3 7.9±0.3 1 0.1±0.1 6.2 +0.1 8 0.2 –0.05 0~10˚ s Applications • Battery power supply for portable equipment 0.6 0.3 0.65 DIP-16 16 9 1 0.81 19.4 1.5 8 3.1min 4.3max 0.2min 3.4 6.5 .0 0.3 –0 +0.1 5 7.6 2.54±0.25 0.5±0.1 0~15 ˚ 0~1 5˚ s Block diagram Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Pin symbol Description Oscillator timing capacitor Capacitor for soft-start, shortcircuit protection and delay Dead time adjustment Non-inverting input to error amplifier Inverting input to error amplifier Error amplifier output Ground CH. 2 Output Power supply CH. 1 Current limiting resistor CH. 1 Output Error amplifier output Inverting input to error amplifier Non-inverting input to error amplifier Reference voltage (0.5V) Dead time adjustment Reference voltage output (2.5V) CT CS DT2 IN2 (+) IN2 (–) FB2 GND OUT2 VCC OUT1R OUT1 FB1 IN1 (–) IN1 (+) 15 16 DT1 REF 1 2.1max FA7611CP(E) s Absolute maximum ratings Item Supply voltage Reference voltage output current Output current Total power dissipation Operating temperature Storage temperature Symbol Rating 22 5 ±50 400 –20 to +85 –40 to +150 Unit V mA mA mW °C °C s Recommended operating conditions Item Supply voltage Feedback resistance Oscillator timing capacitor Oscillator timing resistance Oscillation frequency Symbol Min. 3.6 100 220 10 5 22,000 100 200 Max. 20 Unit V kΩ pF kΩ kHz VCC IOR IO Pd Topr Tstg VCC RNF CT RT fOSC s Electrical characteristics (Ta = 25°C, VCC = 6V, RT = 33kΩ , CT = 1000pF) Reference voltage section Item Output voltage Line regulation Load regulation Output voltage variation due to temperature change Symbol Test condition Min. Typ. 2.475 4 1 Max. 2.525 12 6 1 1 Unit V mV mV % % VREF LINE LOAD VTC1 VTC2 IOR = 1mA 2.425 VCC = 3.6 to 20V, IOR =1mA IOR = 0.1 to 1mA Ta = –20 to +25°C Ta = +25 to +85°C –1 –1 Oscillator section Item Oscillation frequency Frequency variation 1 (due to supply voltage change) Frequency variation 2 (due to temperature change) Symbol Test condition Min. 95 Typ. 115 1 5 Max. 135 Unit kHz % % fOSC fdV fdT CT = 1000pF, RT = 33kΩ VCC = 3.6 to 20V Ta = –20 to +85°C Error amplifier section Item Reference voltage Input bias current Open-loop voltage gain Unity-gain bandwidth Maximum output voltage (Pin 6 and Pin 12) Symbol Test condition Min. 0.484 Typ. 0.494 5 70 0.6 RNF = 100kΩ Max. 0.504 100 Unit V nA dB MHz V 200 40 85 200 mV VB IB AV GB VOM+ VOM– IOM+ VREF–0.2 RNF = 100kΩ VOM = 1V Output source current (Pin 6 and Pin 12) µA PWM comparator section Item Input threshold voltage (Pin 6 and Pin 12) Input threshold voltage (Pin 6 and Pin 12) Symbol Test condition Duty cycle = 0% Duty cycle = 50% Min. Typ. 0.85 1.1 Max. 0.95 Unit V V VTH0 VTH50 2 FA7611CP(E) Dead time adjustment circuit section Item Input bias current (Pin 3 and Pin 15) Input threshold voltage (Pin 3 and Pin 15) Input threshold voltage (Pin 3 and Pin 15) Symbol Test condition Duty cycle = 0% Duty cycle = 50% Min. Typ. 80 0.22 0.46 Max. 300 0.32 Unit nA V V IBDT VTH DT0 VTH DT50 Short-circuit protection circuit section Item Input threshold voltage (Pin 6 and Pin 12) Charge current (Pin 2) Latch-mode threshold voltage (Pin 2) Symbol Test condition Min. 1.20 Pin 2 = 0V, Pin 6, Pin 12 = 2V 10 1.20 Typ. 1.50 30 1.50 Max. 1.80 50 1.80 Unit V VTH PC ICHG VTH LA µA V Undervoltage lockout circuit section Item OFF-to-ON threshold voltage ON-to-OFF threshold voltage Voltage hysteresis Symbol Test condition Min. Typ. 2.65 2.60 50 Max. Unit V V mV VTH ON VTH OFF VHYS Output section Item CH. 1 H-level output voltage (Pin 11) CH. 1 L-level output voltage (Pin 11) CH. 1 Output source current (Pin11) CH. 2 L-level output voltage (Pin 8) Symbol Test condition Min. 3.5 8 Typ. 4.0 0.25 11 1.0 1.5 0.65 Max. Unit V V mA V V01H V01L ISOURCE1 V02L RL = 10kΩ Output sink current = 20mA ROUT1 = 470Ω (Pin 11) = 0V Output sink current = 20mA Overall device Item Supply current Operating-state supply current Symbol Test condition Latch mode Min. Typ. 2.0 3.5 Max. 3.0 6.0 Unit mA mA ICC LA ICC AV RL = ∞ Duty cycle = 50% 3 FA7611CP(E) s Characteristic curves (Ta = 25°C) Oscillation frequency (fOSC ) vs. timing capacitor capacitance (C T) Output duty cycle vs. CS terminal voltage (VCS ) Output duty cycle vs. DT terminal voltage (VDT) Output duty cycle vs. FB terminal voltage (VFB) CH-1 output source current (ISOURCE1) vs. supply voltage (VCC ) L-level output voltage (VO1L ) vs. CH. 1 output sink current (ISINK1 ) 4 FA7611CP(E) L-level output voltage (VO2L) vs. CH. 2 output sink current (ISINK2) Supply current (ICC) vs. supply voltage(VCC) Operating-state supply current (ICCAV) vs. oscillation frequency (fOSC) Error amplifie frequency (f) vs. valtage gain (AV) / phase (θ ) 5 Phase θ [deg] FA7611CP(E) s Application circuit Flyback-transformer type and chopper type buck converter circuit VCC 3.3k 63.5k + – C1 TR D10 + – C11 Flyback 24V 10V 1k 100k 22000p 22k Q1 0.01µ Rout1 + – C2 D12 – + C13 –10V D11 + – C12 VCC 1M 16 15 14 13 12 11 10 9 REF DT1 IN1(+) IN1(–) FB1 OUT1 OUT1R VCC FA7611CP(E) CT 1 CS 2 DT2 IN2(+)IN2(–) FB2 3 4 5 1M 6 GND OUT2 7 8 Q2 R21 L2 Buck 5V C20 + – 56k 1000p 4.7µ 330k 0.01µ R20 D20 820k 1k 2.2k 20.07k Chopper type buck converter and inverting converter circuit 3.3k 30.1k L1 Q1 Rout1 R11 D10 + – C10 Buck 5V 0.01µ 22000p VCC 16 15 REF DT1 1k 14 IN1(+) 13 IN1(–) 12 FB1 11 OUT1 10 OUT1R 9 VCC + – C1 VCC FA7611CP(E) CT 1 56k CS 2 DT2 3 IN2(+) 4 IN2(–) 5 FB2 6 GND 7 OUT2 8 R21 R20 Q2 + – C2 330k 1000p + 4.7µ – D20 47000p Inverting –5V L2 – + C20 820k 1k 100k 2.2k 5.02k 22k Parts tolerances characteristics are not defined in the circuit design sample shown above. When designing an actual circuit for a product, you must determine parts tolerances and characteristics for safe and economical operation. Please connect a capacitor, which the value is about 0.01 µF to 0.1µF, between VCC and REF terminals in order to prevent from irregular output pulse at start-up. 6