APPLICATION NOTE
2
The Cadence® OrCAD® product suite offers a tightly integrated electronic design automation (EDA)
environment. This environment supports complete system design flow starting from schematic capture to
circuit simulation, and finally, PCB realization. Designers can reduce time to market, by leveraging
seamless integration of OrCAD® Capture, PSpice A/D®, and OrCAD® PCB Editor. This application note
also explains how designers can leverage simulation results to drive PCB layout.
A robust and reliable power convertor is essential for the success of any system design. The purpose of
this design example is to demonstrate PSpice capabilities — its integration with other tools used in the
complete design flow by taking a real life example.
AC-DC VRM reference design covers the following aspects of design:
Schematic Entry
Simulation with ideal components to generate component specification
Simulation with real components
Simulation with parasitic
Simulation to observe & refine various design goals
Generating layout constraints based on simulation results
Preparing design for PCB layout
PCB Layout
Tools Used
OrCAD Release 17.2 - 2016
OrCAD Capture
PSpice A/D
OrCAD PCB Editor
Specification
The design goal is to develop a VRM module to meet the following specifications:
Input Voltage 110V (50Hz) , ±10%;
Efficiency at Full Load > 80%
Output Voltage: +48V, ±5%;
Maximum Output Current: 6Amp
Output Current Range: 1-6Amp
1A to 6A load Ripple voltage: 250mV P-P Max
Switching Frequency: ~150 kHz
