FA7612CP

Bipolar IC FA7610CP(N)/12CP(N)/17CP(N)FA7610CP(N)/FA7612CP(N)/FA7617CP(N) For Switching Power Supply Control s Description The FA7610CP(N), 7612CP(N) and 7617CP(N) are bipolar ICs containing basic circuits necessary for PWM-type switching power supply control. To minimize the number of external discrete components, the FA7610CP(N) is provided for a flyback or step-up powersupply circuit, the FA7612CP(N) for a step-down power-supply circuit and FA7617CP(N) for a flyback power supply circuit. s Dimensions, mm SOP-8 8 5 s Features FA7610CP(N) • For flyback transformer-type or step-up power-supply circuit (maximum output duty = 64% typical) • Totem-pole predriver • PWM-type switching power supply control • Low-voltage operation (VCC = 3.6 to 22V) • Latch-mode short-circuit protection function (no malfunction by noise) • Soft-start function • Undervoltage lockout function • One capacitor shared for short circuit protection and for softstart to minimize the number of external discrete components FA7612CP(N) • For step-down power-supply circuit (maximum output duty = up to 100%) • Open collector output • PWM-type switching power supply control • Low-voltage operation (VCC = 3.6 to 22V) • Latch-mode short-circuit protection function (no malfunction by noise) • Soft-start function • Undervoltage lockout function • One capacitor shared for short circuit protection and for softstart to minimize the number of external discrete components FA7617CP(N) • For flyback transformer-type power-supply circuit (maximum output duty = 67% typical) • Open collector output • PWM-type switching power supply control • Low-voltage operation (VCC = 3.6 to 22V) • Latch-mode short-circuit protection function (no malfunction by noise) • Soft-start function • Undervoltage lockout function • One capacitor shared for short circuit protection and for softstart to minimize the number of external discrete components 1 4.9 4 +0.1 –0.05 6.0±0.2 3.9 0.4±0.1 1.27±0.2 DIP-8 8 5 1 9.3 1.5 4 6.5 3.0min 4.5max 3.4 0~8° 0.3 7.6 +0.1 5 –0.0 2.54±0.25 0.5±0.1 0~15 ˚ 0~1 5˚ s Applications • Battery power supply for portable equipment 1.7max 0.20 1 FA7610CP(N)/FA7612CP(N)/FA7617CP(N) s Block diagram FA7610CP(N) Pin No. 1 2 3 4 5 6 7 8 Pin symbol Description Inverting input to error amplifier Error amplifier output Ground Output Power supply Capacitor for soft-start, short-circuit protection and delay Oscillator timing capacitor Reference voltage output (2.5V) IN (–) FB GND OUT VCC CS CT REF FA7612CP(N) Pin No. 1 2 3 4 5 6 7 8 Pin symbol Description Inverting input to error amplifier Error amplifier output Ground Output Power supply Capacitor for soft-start, short-circuit protection and delay Oscillator timing capacitor Reference voltage output (2.5V) IN (–) FB GND OUT VCC CS CT REF FA7617CP(N) Pin No. 1 2 3 4 5 6 7 8 Pin symbol Description Inverting input to error amplifier Error amplifier output Ground Output Power supply Capacitor for soft-start, short-circuit protection and delay Oscillator timing capacitor Reference voltage output (2.5V) IN (–) FB GND OUT VCC CS CT REF 2 FA7610CP(N)/FA7612CP(N)/FA7617CP(N) s Absolute maximum ratings (Ta = 25°C) Item Supply voltage Reference voltage output current Output current Total power dissipation Operating temperature Storage temperature Symbol Rating FA7610C FA7612C/17C 22 5 80 400 –20 to +85 –40 to +150 V mA mA mW °C °C 22 5 ±50 400 –20 to +85 –40 to +150 Unit VCC IOR IO Pd Topr Tstg s Recommended operating conditions Item Symbol FA7610C Min. Supply voltage Feedback resistance Oscillator timing capacitor Oscillator timing resistance Oscillation frequency Max. 20 22,000 100 200 FA7612/17C Min. 3.6 100 220 10 5 22,000 100 500 Max. 20 V kΩ pF kΩ kHz Unit VCC RNF CT RT fOSC 3.6 100 220 10 5 s Electrical characteristics (Ta = 25°C, VCC = 6V, RT = 33kΩ , CT = 1000pF) Reference voltage section Common to FA7610C/12C/17C Item Output voltage Line regulation Load regulation Output voltage variation due to temperature change Symbol Test condition Min. Typ. 2.580 4 1 –1 –1 Max. 2.632 12 6 1 1 Unit V mV mV % % VREF LINE LOAD VTC1 VTC2 IOR = 1mA 2.528 VCC = 3.6 to 20V, IOR = 1mA IOR = 0.1 to 1mA Ta = –20 to +25°C Ta = +25 to +85°C Oscillator section Common to FA7610C/12C/17C Item Oscillation frequency Frequency variation 1 (due to supply voltage change) Frequency variation 2 (due to temperature change) Symbol Test condition Min. 100 Typ. 111 1 5 Max. 122 Unit kHz % % fOSC fdV fdT CT = 1000pF, RT = 33kΩ VCC = 3.6 to 20V Ta = –20 to +85°C Error amplifier section Common to FA7610C/12C/17C Item Reference voltage Input bias current Open-loop voltage gain Unity-gain bandwidth Maximam output voltage (Pin 2) Output source current (Pin 2) Symbol Test condition Min. 0.515 70 0.6 Typ. 0.525 5 Max. 0.535 100 Unit V nA dB MHz V 200 40 85 200 mV VB IB AV GB VOM+ VOM– IOM+ RNF = 100kΩ RNF = 100kΩ VOM = 1V VREF–0.2 µA PWM comparator section Item Symbol Test condition FA7610C Min. Input threshold voltage (pin 2) Input threshold voltage (pin 2) Maximum duty cycle Typ. 0.85 1.1 58 64 75 Max. 0.95 FA7612C Min. Typ. 0.85 1.1 100 63 Max. 0.95 FA7617C Min. Typ. 0.85 1.1 67 71 Max. 0.95 V V % Unit VTH0 VTH50 αM Duty cycle = 0% Duty cycle = 50% (Pin 2 = 1.2V) 3 FA7610CP(N)/FA7612CP(N)/FA7617CP(N) Soft-start circuit section Common to FA7610C/12C/17C Item Input bias current (Pin 6) Input threshold voltage (Pin 6) Input threshold voltage (Pin 6) Symbol Test condition Duty cycle = 0% Duty cycle = 50% Min. Typ. 80 0.22 0.46 Max. 300 0.32 Unit nA V V IBCS VTH CS0 VTH CS50 Short-circuit protection circuit section Common to FA7610C/12C/17C Item Input threshold voltage (Pin 2) Charge current (Pin 6) Latch-mode threshold voltage (Pin 6) Symbol Test condition Pin 6 = 0V, Pin 2 = 2V Min. 1.20 20 1.20 Typ. 1.50 30 1.50 Max. 1.80 40 1.80 Unit V VTH PC ICHG VTH LA µA V Undervoltage lockout circuit section Common to FA7610C/12C/17C Item OFF-to-ON threshold voltage ON-to-OFF threshold voltage Voltage hysteresis Symbol Test condition Min. Typ. 2.70 2.52 60 180 Max. Unit V V mV VTH ON VTH OFF VHYS Output section Item H-level output voltage (Pin 4) L-level output voltage (Pin 4) Output source current (Pin 4) Symbol Test condition FA7610C Min. Typ. 4.0 0.25 8 11 0.65 14 — 3.5 FA7612C/17C Max. Min. — Typ. — 0.9 — Max. — 1.5 — V V mA Unit VOH VOL ISOURCE RL = 10kΩ Output sink current = 20mA Pin 4 = 0V Overall device Item Supply current Operating-state supply current Symbol Test condition Latch mode FA7610C Min. Typ. 1.6 2.6 2.2 3.8 FA7612C/17C Max. Min. Typ. 1.5 1.8 Max. 2.2 3.0 mA mA Unit ICC LA ICC AV RL = ∞ Duty cycle = 50% 4 FA7610CP(N)/FA7612CP(N)/FA7617CP(N) s Characteristic curves (Ta = 25°C) Oscillation frequency(fOSC ) vs. timing capacitor capacitance(C T) Output duty cycle vs. CS terminal voltage(VCS ) Output source current (Isource) vs. supply voltage(VCC ) L-level output voltage(VOL ) vs. output sink current (ISINK ) Supply current(ICC) vs. supply voltage(VCC) Error amplifier frequency(f) vs. voltage gain(AV) / phase (θ) 5 FA7610CP(N)/FA7612CP(N)/FA7617CP(N) s Application circuit FA7610CP(N) Flyback-transformer type converter circuit FA7612CP(N) Chopper type buck converter circuit 6 FA7610CP(N)/FA7612CP(N)/FA7617CP(N) FA7617CP(N) Flyback-transformer type converter circuit 2.5V 330k 180k 4.7µ 1000p VCC R2 + R3 Q1 8 7 6 5 0.01µ VCC 36k 30µA VREF OSC. S.C.P U.V.L.O + ER. AMP + + PWM + OFF TR OFF +5V + + L.O 0.52V + 1 2 3 4 0.01µ + 1k 2.2k 18.75k –5V 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. 7