56.6.6.2 Source Clock Selection Criteria
The large number of source clocks can make selection difficult. The relationship between the value in the PWM Channel Period Register (PWM_CPRDx) and the PWM Channel Duty Cycle Register (PWM_CDTYx) helps the user select the appropriate clock. The event number written in the Period Register gives the PWM accuracy. The Duty-Cycle quantum cannot be lower than 1/CPRDx value. The higher the value of PWM_CPRDx, the greater the PWM accuracy.
For example, if the user sets 15 (in decimal) in PWM_CPRDx, the user is able to set a value from between 1 up to 14 in PWM_CDTYx. The resulting duty-cycle quantum cannot be lower than 1/15 of the PWM period.