Offline flyback controller for isolated supplies
The Infineon ICE2AS01GHUMA1 is an offline flyback PWM controller designed for isolated AC-DC converter stages. It switches at 100 kHz and operates from a Vcc supply rail of 8.5 V to 21 V, with a startup threshold of 13.5 V. The 72% maximum duty cycle sets the on-time ceiling for the primary switch, which matters when sizing the transformer turns ratio and bulk capacitor for hold-up time.
Protection and control feature set
Built-in fault protection covers current limiting, open-loop detection, overload, over-temperature, and over-voltage conditions — the controller shuts down or folds back without external supervisory circuitry. A soft-start function ramps the duty cycle on power-up, reducing inrush stress on the output capacitor and the primary MOSFET. Output isolation is supported — the controller drives a primary-side switch while the feedback loop crosses the isolation barrier via an optocoupler or a transformer winding.
The narrow-body SOIC footprint is standard for low-pin-count power controllers and mates with common 1.27 mm pitch land patterns. Supplied in Bulk packaging — no tape-and-reel quantity, so plan for tube or tray handling at the pick-and-place feeder.
Confirm the BOM position against the PG-DSO-8 footprint before committing the layout.