NCP1271ADAPGEVB 19V @ 60W, 85 ~ 264VAC in

The NCP1271ADAPEVB is an example circuit using NCP1271 (65 kHz version) in flyback topology. The 19 V, 3.0 A circuit delivers above 85% from universal input (85 to 265 Vac). The no load standby consumption is 83 mW at 230 Vac. The NCP1271 is one of the latest fixed-frequency current-mode PWM switching controllers with (1) soft-skip standby operation for low-level audible noise (2) integrated high-voltage startup for saving PCB space and power (3) adjustable skip level to minimize standby power and (4) optional external latch protection features.

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.