KA7525B

www.fairchildsemi.com Power Factor Correction Controller Features Internal Start-up Timer Internal Current Sense Blanking Which Eliminates the Need for an External R/C filter Overvoltage Comparator Eliminates Runaway Output Voltage Zero Current Detector One Quadrant Multiplier Trimmed 1.5% Internal Bandgap Reference Under Voltage Lock Out with 2.1V of Hysteresis Totem Pole Output with High State Clamp Low Start-up and Operating Current 8-Pin DIP or 8-Pin SOP. KA7525B Description The KA7525B provides simple and high performance active power factor correction. KA7525B is optimized for electronic ballast and low power, high density power supplies requiring a minimum board area, reduced component count and low power dissipation. Addition of internal current sense blanking (Internal R,C) eliminates the need for an external R/C filter. Internal clamping of the error amplifier and multiplier outputs improves turn on overshoot characteristics and current limiting. Special circuitry has also been added to prevent no load runaway conditions. Output drive clamps limiting power MOSFET gate drive independent of supply voltage greatly enhance the products practical application. Applications Electronic Ballast SMPS 8-DIP 1 8-SOP 1 Rev.1.0.1 ©2002 Fairchild Semiconductor Corporation KA7525B Pin Assignments INV 1 8 Vcc EA OUT 2 7 OUT MULT 3 6 GND CS 4 5 Idet (Top View) Pin Definitions Pin Number 1 2 3 Pin Name INV EA_OUT MULT Pin Function De...