STMicroelectronics STACF01B, Flyback Regulator DC-DC Controller, 20mA 23-Pin, QFN 5x5 [STACF01B]; 330-369

The STMicroelectronics Active clamp fly back controller with non-complementary driving of the active clamp (high-side, HS) switch. It is specifically intended for high performance AC-DC adapters with GaN HEMTS rated up to 100 W and beyond, which are aimed at high efficiency as well as high power density. The ICs seamlessly change operating mode with loading conditions to optimize efficiency under an extremely wide range of loads: variable frequency with frequency fold back at heavy-medium load, bottom-clamped, load-proportional frequency at light load, burst mode at very light, and no-load.

Non-complementary control of active clamp fly back converter

Multimode operation optimizes efficiency over a very wide load range

Up to 500 kHz operating frequency with programmable dead time

Automatic reverse current control for ZVS of low-side switch

ZCD circuit for demagnetization instant detection and OVP setting

Embedded high-voltage startup and active x-cap discharge circuit

Integrated buck-boost regulator for wide output voltage range

Very low quiescent current enables ultra-low no-load input power

Full set of protection features

Interface with PFC controller