PWM Controller, Soft-Skip™ Standby, with Adjustable Skip Level and External Latch

The NCP1271 represents a new, pin to pin compatible, generation of the successful 7 pin current mode NCP12XX product series. The controller allows for excellent stand by power consumption by use of its adjustable Soft Skip mode and integrated high voltage startup FET. This proprietary Soft Skip also dramatically reduces the risk of acoustic noise. This allows the use of inexpensive transformers and capacitors in the clamping network. Internal frequency jittering, ramp compensation, timer based fault detection and a latch input make this controller an excellent candidate for converters where ruggedness and component cost are the key constraints.