Datasheet

Table Of Contents
© 2007 Microchip Technology Inc. DS39605F-page 125
PIC18F1220/1320
FIGURE 15-10: PWM DIRECTION CHANGE (ACTIVE-HIGH)
FIGURE 15-11: PWM DIRECTION CHANGE AT NEAR 100% DUTY CYCLE (ACTIVE-HIGH)
DC
PWM Period
(1)
SIGNAL
Note 1: The direction bit in the CCP1 Control register (CCP1CON<7>) is written any time during the PWM cycle.
2: When changing directions, the P1A and P1C toggle one Timer2 count before the end of the current PWM cycle.
The modulated P1B and P1D signals are inactive at this time.
PWM Period
One Timer2 Count
(2)
P1A
P1B
P1C
P1D
DC
Forward Period Reverse Period
P1A
t
ON
t
OFF
t = t
OFF
– t
ON
P1B
P1C
P1D
External Switch D
Potential
Shoot-Through
Current
Note 1: t
ON
is the turn-on delay of power switch QC and its driver.
2: t
OFF
is the turn-off delay of power switch QD and its driver.
External Switch C
t1
DC
DC