www.fairchildsemi.com FAN4822 ZVS Average Current PFC Controller Features General Description Average current sensing, continuous boost, leading edge The FAN4822 is a PFC controller designed specically for PFC for low total harmonic distortion and near unity high power applications. The controller contains all of the power factor functions necessary to implement an average current boost Built-in ZVS switch control with fast response for high PFC converter, along with a Zero Voltage Switch (ZVS) con- efciency at high power levels troller to reduce diode recovery and MOSFET turn-on Average line voltage compensation with brownout control losses. Current fed gain modulator improves noise immunity and provides universal input operation The average current boost PFC circuit provides high power Overvoltage comparator eliminates output runaway due factor (>98%) and low Total Harmonic Distortion (THD). to load removal Built-in safety features include undervoltage lockout, over- UVLO, current limit, and soft-start voltage protection, peak current limiting, and input voltage Precision 1.3% reference brownout protection. The ZVS control section drives an external ZVS MOSFET which, combined with a diode and inductor, soft switches the boost regulator. This technique reduces diode reverse recov- ery and MOSFET switching losses to reduce EMI and maxi- mize efciency. Block Diagram 1 8 2 VEAO GND IEAO FB VEA V CC 14 OVP 12 V CCZ + FB + 2.5V R+ 13.5V IEA 2.7V + I AC + GAIN 4 MODULATOR S Q V RMS I LIMIT 5 R 1V + R I SENSE 3 PFC OUT 11 R C T T 6 OSC S Q V CCZ R Q REF ZVS OUT 13 REF 10 S Q + ZV SENSE PWR GND 7 R Q 9 REV. 1.0.1 8/10/01 FAN4822 PRODUCT SPECIFICATION Pin Conguration FAN4822 FAN4822 14-Pin DIP (P14) 16-Pin SOIC (S16W) VEAO 1 14 FB VEAO 1 16 FB IEAO 2 13 REF IEAO 2 15 REF I 3 12 V I 3 14 V SENSE CC SENSE CC I 4 11 PFC OUT I 4 13 PFC OUT AC AC V 5 10 ZVS OUT V 5 12 ZVS OUT RMS RMS R C 6 9 PWR GND R C 6 11 PWR GND T T T T ZV SENSE 7 8 GND ZV SENSE 7 10 GND N/C 8 9 N/C TOP VIEW TOP VIEW Pin Description (Pin numbers is parentheses are for 16-pin package) Pin Name Function 1 (1) VEAO Transconductance voltage error amplifier output. 2 (2) IEAO Transconductance current error amplifier output. 3 (3) I Current sense input to the PFC current limit comparator. SENSE 4 (4) I PFC gain modulator reference input. AC 5 (5) V Input for RMS line voltage compensation. RMS 6 (6) R C Connection for oscillator frequency setting components. T T 7 (7) ZV SENSE Input to the high speed zero voltage crossing comparator. 8 (10) GND Analog signal ground. 9 (11) PWR GND Return for the PFC and ZVS driver outputs. 10 (12) ZVS OUT ZVS MOSFET driver output. 11 (13) PFC OUT PFC MOSFET driver output. 12 (14) V Shunt-regulated supply voltage. CC 13 (15) REF Buffered output for the internal 7.5V reference. 14 (16) FB Transconductance voltage error amplifier input. Absolute Maximum Ratings Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum rat- ings are stress ratings only and functional device operation is not implied. Parameter Min Max Unit Shunt Regulator Current (I)55mA CC Peak Driver Output Current 500 mA Analog Inputs 0.3 7 V Junction Temperature 150 C Storage Temperature Range 65 150 C Lead Temperature (Soldering, 10 sec) 150 C Thermal Resistance (JA) Plastic DIP 80 C/W Plastic SOIC 110 C/W 2 REV. 1.0.1 8/10/01