PWM Current-Mode Controller for Universal Off-Line Supplies Featuring Standby and Short Circuit Protection

Housed in SOIC−8 or PDIP−8 package, the NCP1203 represents a major leap toward ultra−compact Switchmode Power Supplies and represents an excellent candidate to replace the UC384X devices.

Due to its proprietary SMARTMOS™Very High Voltage Technology, the circuit allows the implementation of complete off−line AC−DC adapters, battery charger and a high−power SMPS with few external components.

With an internal structure operating at a fixed 40 kHz, 60 kHz or 100 kHz switching frequency, the controller features a high−voltage startup FET which ensures a clean and loss−less startup sequence.

Its current−mode control naturally provides good audio−susceptibility and inherent pulse−by−pulse control.