ML4822

Average current sensing, continuous boost, leading edge PFC for low total harmonic distortion and near unity power factor
Built-in ZVS switch control with fast response for high efficiency at high power levels
Average line voltage compensation with brownout control
Current fed gain modulator improves noise immunity and provides universal input operation
Overvoltage comparator eliminates output "runaway" due to load removal
UVLO, current limit, and soft-start
Precision 1% reference

The ML4822 is a PFC controller designed specifically for high power applications. The controller ML4822 contains all of the functions necessary to implement an average current boost PFC converter, along with a Zero Voltage Switch (ZVS) controller to reduce diode recovery and MOSFET turn-on losses.

The average current boost PFC circuit of ML4822 provides high power factor (>98%) and low Total Harmonic Distortion (THD). Built-in safety features include undervoltage lockout, overvoltage protection, peak current limiting, and input voltage brownout protection.

The ZVS control section of ML4822 drives an external ZVS MOSFET which, combined with a diode and inductor, soft switches the boost regulator. This technique reduces diode reverse recovery and MOSFET switching losses to reduce EMI and maximize efficiency.