KA3843AC Datasheet | Fairchild Semiconductor

.. .fairchildsemi. SMPS Controller Features - - - - - - - Low start current 0.2m A (typ) Operating range up to 500k Hz Cycle by cycle current limiting Under voltage lock out with hysteresis Short shutdown delay time: typ.100ns High current totem-pole output Output swing limiting: 22V Description The KA3843AC are fixed PWM controller for Off-Line and DC to DC converter applications. The internal circuits include UVLO, low start up current circuit, temperature pensated reference, high gain error amplifier, current sensing parator, and high current totem-pole output for driving a POWER MOSFET. Also KA3843AC provide low start up current below 0.3m A and short shutdown delay time typ. 100ns. The KA3843AC is 8.4V(on) and 7.6V(off). The KA3843AC can operate within 100% duty cycle. 8-DIP 8-SOP Internal Block Diagram 7 VCC 29V VREF 8 Internal Bias 1/2VREF 5V VREF SET/ RESET UVLO 5 GND Good LOGIC 7 Error Amp + C.S PWM p. LATCH 1/3 1V S R 22V 6 OUTPUT PWR VC VFB 2 P 1 5 PWR C.S 3 RT/CT 4 OSCILLATOR Rev. 1.0.1 ©2005 Fairchild Semiconductor...