Multi-topology PWM controller for isolated supplies
The Texas Instruments UCC3804D is an offline PWM controller supporting Boost, Buck, Flyback, and Forward topologies, making it a flexible choice for isolated and non-isolated AC-DC converters up to 1 MHz switching frequency. With a maximum duty cycle of 49%, it is suited for single-ended topologies like flyback and forward converters where the transformer core resets during the off-time. The 8.3 V to 12 V supply range and 12.5 V startup threshold align with standard bias rails from an auxiliary winding or a bootstrap circuit.
Package and board-fit for 8-SOIC
Housed in an 8-SOIC package (0.154" width, 3.90 mm body), the UCC3804D mounts on standard surface-mount pads and is supplied in Tube format.