STCMB1

STCMB1 is a transition mode PFC with X-cap discharge and LLC resonant combo controller. The PFC section uses a proprietary constant on-time control methodology that does not require a sinusoidal input reference, thereby reducing the system cost and external component count. It includes also a complete set of protections: a cycle-by-cycle OCP, an output OVP, a feedback failure, an AC brown-out, boost inductor saturation and inrush current detection both at the start-up and after mains sags or missing cycles. The half-bridge (HB) section provides two complementary outputs that drive the high-side and low-side MOSFET 180° out-of-phase. The deadtime inserted between the turn-off of an either switch and the turn-on of the other is automatically adjusted to ensure zero voltage switching and higher efficiency from low to full load. A proprietary control method, time shift control - TSC, improves dynamic behaviour and input ripple rejection resulting in a cleaner output voltage.

• 800V high voltage start-up with integrated input voltage sensing
• Active input filter capacitor discharge circuitry for reduced standby power
• Independent debug mode for both converters
• Enhanced constant on-time PFC with input voltage feedforward, THD optimizer
• Proprietary time shift control for improved input ripple rejection and dynamic response
• Half-bridge operation up to 750KHz with self-adjusting deadtime
• DC brown-out, two-level OCP, HSP function for anti-capacitive mode protection and safe start-up
• Synchronous burst mode operation with PFC enhances light-load efficiency
• SO20W package