UCC38503
Overview
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 average current-mode control.
- Combines PFC and Downstream Converter Controls
- Controls Boost Preregulator to Near-Unity Power Factor
- Accurate Power Limiting
- Improved Feedforward Line Regulation
- Peak Current-Mode Control in Second Stage
- Programmable Oscillator
- Leading-Edge/Trailing-Edge Modulation for Reduced Output Ripple
- Low Start-up Supply Current
- Synchronized Second Stage Start-Up, with Programmable Soft-start
- Programmable Second Stage Shutdown
