1 MHz flyback controller — no internal FET, so plan the external switch
The Texas Instruments UCC28780D is an offline flyback controller in a 16-SOIC package. It runs a flyback topology with isolated output, switching up to 1 MHz. That frequency lets you shrink the transformer, but the controller has no built-in MOSFET — you pick the external switch, which means the BOM includes a FET plus its gate-drive loop. The supply range is 12 V to 34 V on Vcc, with a 17.5 V start-up threshold.
Protection set and temperature range
Fault protection covers over-current, over-temperature, over-voltage, and short-circuit. That is a solid safety net for an offline supply where a crowbar or latch-off is expected. The junction temperature range is -40°C to 125°C, which puts it in the industrial and automotive-grade bracket — fine for outdoor PSUs, motor drives, or under-hood bias supplies.
Lifecycle and compliance
The UCC28780D is listed as Active in production status and ROHS3 compliant.
