NCP1622BCASNT1G

The NCP1622BCASNT1G is an advanced power factor controller IC designed by ON Semiconductor to drive PFC boost stages. It utilizes an innovative Valley Synchronized Frequency Fold-back (VSFF) method, enabling high efficiency at both nominal and light load conditions by minimizing standby losses.

This controller operates classically in Critical Conduction Mode (CrM) when the control voltage exceeds a programmable threshold. Below this threshold, it linearly decays the switching frequency down to approximately 30 kHz, maximizing efficiency at low current levels. The NCP1622 supports near-unity power factor even with reduced switching frequencies and includes features like On-time Modulation for proper current shaping in VSFF mode.

Key features include a wide VCC range of 9.5 V to 30 V, high drive capability (-500 mA / +800 mA), and robust safety features such as thermal shutdown, over-voltage protection, brown-out detection, and over-current limitation. It is housed in a compact 6-TSOP package, suitable for robust and compact PFC stages with minimal external components.

Typical applications include PC power supplies, lighting ballasts (LED, fluorescent), flat TVs, and all offline appliances requiring power factor correction.