UCC28503 Datasheet

UCC28503 BiCMOS PFC/PWM Combination Controller

The UCC2850x family provides all of the control functions necessary for an active power-factorcorrected preregulator and a second-stage dc-to- dc converter. The controller achieves near-unity power factor by shaping the ac input line current waveform to correspond to the ac input-line voltage using .

Features

D Combines PFC and Downstream Converter Controls D Controls Boost Preregulator to Near-Unity Power Factor D Accurate Power Limiting D Improved Feedforward Line Regulation D Peak Current-Mode Control in Second Stage D Programmable Oscillator D Leading-Edge/Trailing-Edge Modulation for Reduced Output Ripple D Low Start-up Supply Current D Synchronized Second Stage Start-Up, with Programmable Soft-start D Programmable Second Stage Shutdown DESCRIPTION The UCC2850x family provides all of the control functions necessary for an active power-factorcorrected preregulator and a second-stage dc-to- dc c.