Microchip dsPIC33F GS DSC AC-DC Reference Design

Microchip introduced an AC/DC reference design based on the new dsPIC33F “GS” series of digital-power Digital Signal Controllers (DSCs). The reference design shows how digital-power techniques are applied to reduce component count, lower product cost, eliminate oversized components, and incorporate topology flexibility to innovate the best solution for the application. Complete documentation, including software and Gerber files, can be downloaded for free.

Microchip dsPIC SMPS AC-DC Reference Design

The reference design features a Microchip’s dsPIC33F “GS” series DSC, which controls the PFC boost circuit and the primary-side ZVT full-bridge circuit. A second “GS” series dsPIC33F monitors the 12 VDC bus voltage and controls the four buck converters. The two dsPIC DSCs communicate across the isolation boundary via Universal Asynchronous Receiver Transmitters (UARTs).

AC/DC Reference Design Specifications

  • Universal Inputs (85V – 265V AC, 45 – 65 Hz)
  • Operation up to 300W on 12V output
  • Power Factor Performance of 0.99 at full load ( 110Vac/220Vac)
  • Various Fault Indication and Protection
  • Excellent Dynamic load performance and Output Sequencing
  • Separate boards for digital signals (Signal Board) and Power stage (Power Board)
  • Signal Board has two dsPIC33F16GS504 devices controlling different power stages
  • MPLAB ICD 2 /ICD 3 or REAL ICE support ready
  • Boost PFC (PF > 0.98)
  • Soft-start (programmable)
  • Full-bridge ZVT (soft-switching)
  • Synchronous rectification
  • 12-Volt intermediate bus
  • Multi-phase Synchronous Buck converter 3.3V output
  • Single-phase 5.0V output
  • Automatic fault handling
  • Remote power-management capabilities
  • Flexible start-up capabilities
  • Greater than 90% efficiency on each of the four power-conversion stages

More info: dsPIC SMPS AC-DC Reference Design