User manual

PSMC DESIGNER
USER’S GUIDE
 2012-2013 Microchip Technology Inc. DS40001671B-page 9
Chapter 1. PSMC Designer Overview
1.1 INTRODUCTION
The PSMC peripheral is a sophisticated programmable switch mode controller
intended to operate power conversion applications with little or no software
intervention. The peripheral capabilities range from simple, single channel PWM
generation to multi-channel complementary waveforms with dead bands between
transitions. PWM modes include:
•PWM
• Push-Pull
• Full-bridge
• Push-Pull Full-bridge
• Pulse skipping
• High resolution fixed duty cycle
• 6-step 3-phase operation
Every mode, except the 6-step, has a complementary output mode, which drives at
least two channels that are the complement of each other.
The PSMC also supports various driver and feedback configurations with the following
programmable features:
• Dead band – delays the output drive for a time after the complement of that output
turns off
• Blanking – Suppresses feedback signals for a time after the drive transitions on
and off
• Asynchronous inputs – pulse Start and Stop events can be triggered by external
asynchronous signals in combination with, or independent of, an internal time
base
• Shutdown – immediate safe shutdown driven by an external asynchronous Fault
signal
• Modulation – the PWM can be operated as a carrier and modulated by an
independent input
There are thirty Special Function Registers (SFRs) in the PSMC configuration setup.
Setting all thirty registers with the appropriate values for desired operation can be a
daunting task. The PSMC Designer GUI was created to simplify that effort.
The GUI divides the PSMC into up to eleven major functions. These functions are
shown in relation to each other in block diagram format in the main GUI window.
Clicking on a block opens the control GUI for that function. The user is guided through
the PSMC configuration design by completing signal paths and control options within
each function by selecting switch positions. Entry boxes for times and frequencies
appear within the diagrams where numeric entry is required.
There are two options for transferring the completed PSMC configuration to your
project. One is to copy the code into the clipboard buffer which can then be pasted into
your source code. The other transfer method is to generate an output file that can be
included by reference in your source code. Include files are also the means by which
PSMC configurations are stored for later retrieval by the PSMC designer.