POWER FACTOR CORRECTION CONTROLLER OF CRITICAL DUCTING

DESCRIPTION
The  SA7527  provides  simple  and  high  performance active  power factor  correction. The  SA7527 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.

FEATURES
* Internal start-up timer
* Internal R/C filter eliminates the need for an external R/C filter
* Very precise adjustable output over voltage protection
* Zero current detector
* One quadrant multiplier
* Trimmed 1.5% internal band gap reference
* Under voltage lockout with 3V of hysteresis
* Totem pole output with high state clamp
* Low start-up and operating current
* 8-pin DIP or 8-pin SOP

APPLICATIONS
* Electronic ballast
* SMPS