PXS20RM Datasheet, PDF (58/1368 Pages) Freescale Semiconductor, Inc – PXS20 Microcontroller

Introduction
• Queueing operation possible through use of the eDMA
• General purpose I/O functionality on pins when not used for SPI
1.4.30 Pulse Width Modulator (PWM)
The PWM module contains four PWM channels, each of which is configured to control a single
half-bridge power stage. Two modules are included on 257 MAPBGA devices; on the 144 LQFP package,
only one module is present. Additionally, four fault input channels are provided per PWM module.
This PWM is capable of controlling most motor types, including:
• AC induction motors (ACIM)
• Permanent Magnet AC motors (PMAC)
• Brushless (BLDC) and brush DC motors (BDC)
• Switched (SRM) and variable reluctance motors (VRM)
• Stepper motors
A PWM module implements the following features:
• 16 bits of resolution for center, edge aligned, and asymmetrical PWMs
• Maximum operating frequency as high as 120 MHz
— Clock source not modulated and independent from system clock (generated via secondary
FMPLL)
• Fine granularity control for enhanced resolution of the PWM period
• PWM outputs can operate as complementary pairs or independent channels
• Ability to accept signed numbers for PWM generation
• Independent control of both edges of each PWM output
• Synchronization to external hardware or other PWM supported
• Double buffered PWM registers
— Integral reload rates from 1 to 16
— Half cycle reload capability
• Multiple ADC trigger events can be generated per PWM cycle via hardware
• Fault inputs can be assigned to control multiple PWM outputs
• Programmable filters for fault inputs
• Independently programmable PWM output polarity
• Independent top and bottom deadtime insertion
• Each complementary pair can operate with its own PWM frequency and deadtime values
• Individual software control for each PWM output
• All outputs can be forced to a value simultaneously
• PWMX pin can optionally output a third signal from each channel
• Channels not used for PWM generation can be used for buffered output compare functions
• Channels not used for PWM generation can be used for input capture functions
1-18
PXS20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor