PIC18F2331/2431/4331/4431
18.0
POWER CONTROL PWM
MODULE
The PWM module has the following features:
• Up to eight PWM I/O pins with four duty cycle
generators. Pins can be paired to get a complete
half-bridge control.
• Up to 14-bit resolution, depending upon the PWM
period.
• “On-the-fly” PWM frequency changes.
• Edge and Center-Aligned Output modes.
• Single-Pulse Generation mode.
• Programmable dead-time control between paired
PWMs.
• Interrupt support for asymmetrical updates in
Center-Aligned mode.
• Output override for Electrically Commutated
Motor (ECM) operation; for example, BLDC.
• Special Event Trigger comparator for scheduling
other peripheral events.
• PWM outputs disable feature sets PWM outputs
to their inactive state when in Debug mode.
The Power Control PWM module supports three PWM
generators
and
six
output
channels
on
PIC18F2331/2431 devices, and four generators and
eight channels on PIC18F4331/4431 devices. A simpli-
fied block diagram of the module is shown in
and
show how
the module hardware is configured for each PWM
output pair for the Complementary and Independent
Output modes.
Each functional unit of the PWM module will be
discussed in subsequent sections.
The Power Control PWM module simplifies the task of
generating multiple, synchronized Pulse-Width
Modulated (PWM) outputs for use in the control of
motor controllers and power conversion applications.
In particular, the following power and motion control
applications are supported by the PWM module:
• Three-Phase and Single-Phase AC Induction
Motors
• Switched Reluctance Motors
• Brushless DC (BLDC) Motors
• Uninterruptible Power Supplies (UPS)
• Multiple DC Brush Motors
2010 Microchip Technology Inc.
DS39616D-page 173
MICROCHIP [ MICROCHIP TECHNOLOGY ]
