PIC18F2331 Datasheet, PDF (183/396 Pages) Microchip Technology – 28/40/44-Pin Enhanced Flash Microcontrollers with nanoWatt Technology, High Performance PWM and A/D

PIC18F2331/2431/4331/4431
17.0 POWER CONTROL PWM
MODULE
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
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 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 PIC18F2X31
devices, and four generators and eight channels on
PIC18F4X31 devices. A simplified block diagram of the
module is shown in Figure 17-1. Figure 17-2 and
Figure 17-3 show how the module hardware is config-
ured 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.
 2003 Microchip Technology Inc.
Preliminary
DS39616B-page 181