Information

© 2008 Microchip Technology Inc. DS39646C-page 199
PIC18F8722 FAMILY
FIGURE 18-8: PWM DIRECTION CHANGE
FIGURE 18-9: PWM DIRECTION CHANGE AT NEAR 100% DUTY CYCLE
(1)
DC
Period
(1)
SIGNAL
Note 1: The direction bit in the ECCP1 Control register (CCP1CON<7>) is written any time during the PWM cycle.
2: When changing directions, the P1A and P1C signals switch before the end of the current PWM cycle at intervals
of 4 T
OSC, 16 TOSC or 64 TOSC, depending on the Timer2 prescaler value. The modulated P1B and P1D signals
are inactive at this time.
Period
(Note 2)
P1A (Active-High)
P1B (Active-High)
P1C (Active-High)
P1D (Active-High)
DC
Forward Period Reverse Period
P1A
t
ON
(2)
t
OFF
(3)
t = t
OFF
– t
ON
P1B
P1C
P1D
External Switch D
Potential
Shoot-Through
Current
Note 1: All signals are shown as active-high.
2: t
ON
is the turn-on delay of power switch QC and its driver.
3: t
OFF
is the turn-off delay of power switch QD and its driver.
External Switch C
t1
DC
DC