onsemi (Ansemi)

TSOP-6-1.5mm

taping

3000

The 6-pin PFC controller NCP1622 is suitable for driving the PFC boost stage. It is based on the innovative Valley Synchronous Frequency Foldback (VSFF) method. In this mode, the circuit normally operates in critical conduction mode (CrM) when the inductor current exceeds the programmed value Vctrl,FF. When Vcontrol is lower than this preset level Vctrl,FF, the NCP1622 (versions [B**] and [D**]) will linearly reduce the frequency to about 30 kHz until Vcontrol reaches the skip mode threshold. VSFF maximizes energy efficiency at nominal and light loads. In particular, standby losses are minimized. Similar to the internal circuitry in the FCCrM controller, near unity power factor is achieved even at reduced switching frequency. Using TSOP6 encapsulation, the circuit has the features required for a robust and compact PFC stage with few external components.