FAN4822 Datasheet | Fairchild Semiconductor

Features - 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 pensation with brownout control - Current fed gain modulator improves noise immunity and provides universal input operation - Overvoltage parator eliminates output “runaway” due to load removal - UVLO, current limit, and soft-start - Precision 1.3% reference General Description The FAN4822 is a PFC controller designed specifically for high power applications. The controller 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 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 drives an external ZVS MOSFET which, bined 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. Block Diagram FB 14 2.5V IAC 4 VRMS 5 ISENSE 3 RTCT 6 VCCZ REF 13 REF + VEAO - + VEA IEAO OVP VCC VCCZ 13.5V 2.7V + - - R+ + FB IEA + GAIN MODULATOR R- - S I LIMIT - 1V + - Q R PFC OUT 11 S R Q Q ZVS OUT 10 S R Q Q PWR GND 9 ZV SENSE 7 - - REV. 1.0.1 8/10/01 PRODUCT SPECIFICATION Pin Configuration FAN4822 14-Pin DIP (P14) VEAO IEAO ISENSE IAC VRMS RTCT ZV SENSE 1 2 3 4 5 6 7 14 13 12 11 10 9 8 FB REF VCC PFC OUT ZVS OUT PWR GND GND VEAO IEAO ISENSE IAC VRMS RTCT ZV SENSE N/C FAN4822 16-Pin SOIC (S16W) 1 2 3 4 5 6 7 8 TOP VIEW 16 15 14 13 12 11 10 9 FB REF VCC PFC OUT ZVS OUT PWR GND GND N/C TOP VIEW Pin Description (Pin numbers is...