The FAN7527B provides simple and high performance active power factor correction. The FAN7527B is optimized for electronic ballasts and low power and high density power supplies which require minimum board size, reduced external components and low power dissipation. Because the R/C filter is included in the current sense block, the external R/C filter is not necessary. Special circuitry has also been added to prevent no load runaway conditions. Regardless of the supply voltage, the output drive clamping circuit limits the overshoot of the power MOSFET gate drive. It greatly enhances the system reliability.