PIC16F631/677/685/687/689/690
FIGURE 11-7:
EXAMPLE ENHANCED PWM OUTPUT RELATIONSHIPS (ACTIVE-LOW STATE)
PR2+1
Pulse
Width
0
Signal
P1M<1:0>
Period
P1A Modulated
P1A Modulated
P1B Modulated
P1A Active
(Single Output)
00
10
Delay(1)
Delay(1)
(Half-Bridge)
(Full-Bridge,
Forward)
P1B Inactive
P1C Inactive
P1D Modulated
P1A Inactive
P1B Modulated
P1C Active
01
(Full-Bridge,
Reverse)
11
P1D Inactive
Relationships:
•
•
•
Period = 4 * TOSC * (PR2 + 1) * (TMR2 Prescale Value)
Pulse Width = TOSC * (CCPR1L<7:0>:CCP1CON<5:4>) * (TMR2 Prescale Value)
Delay = 4 * TOSC * (PWM1CON<6:0>)
Note 1: Dead-band delay is programmed using the PWM1CON register (Section 11.4.6 “Programmable Dead-Band Delay
mode”).
© 2007 Microchip Technology Inc.
DS41262D-page 135