4.3 PWM Period

The PWM period is specified by the T2PR register of Timer2. The PWM period can be calculated using the formula in Equation 4-1.

Equation 4-1. PWM Period

$P W M P e r i o d = [(T 2 P R + 1)] • 4 • T_{O S C} • (T M R 2 \Pr e s c a l e V a l u e)$

$w h e r e :$

$T_{O S C} = \frac{1}{F_{O S C}}$

When T2TMR is equal to T2PR, the following three events occur on the next increment event:

T2TMR is cleared.
The CCPx pin is set. (Exception: If the PWM duty cycle = 0%, the pin will not be set.)
The PWM duty cycle is transferred from the CCPRx register into a 10-bit buffer.

Important: The Timer postscaler is not used in the determination of the PWM frequency.

TB3275