RM0046 FlexPWM
Doc ID 16912 Rev 5 643/936
25 FlexPWM
25.1 Overview
The pulse width modulator module (PWM) contains four PWM submodules, each of which
capable of controlling a single half-bridge power stage and two fault input channels.
This PWM is capable of controlling most motor types: AC induction motors (ACIM),
Permanent Magnet AC motors (PMAC), both brushless (BLDC) and brush DC motors
(BDC), switched (SRM) and variable reluctance motors (VRM), and stepper motors.
25.2 Features
● 16-bit resolution for center, edge-aligned, and asymmetrical PWMs
● PWM outputs can operate as complimentary pairs or independent channels
● Can 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 output trigger events can be generated per PWM cycle via hardware
● Support for double switching PWM outputs
● 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 programmed to change simultaneously via a “Force Out” event
● PWMX pin can optionally output a third PWM signal from each submodule
● Channels not used for PWM generation can be used for buffered output compare
functions
● The option to supply the source for each complementary PWM signal pair from any of
the following:
– External digital pin
– Internal timer channel
– External ADC input, taking into account values set in ADC high and low limit
registers.