Specifications

dsPIC33F/PIC24H Family Reference Manual
DS70323E-page 43-44 © 2008-2012 Microchip Technology Inc.
43.5.8 Independent PWM Time Base
The PWM functionality in the independent time base is illustrated in Figure 43-10.
Figure 43-10: Independent Time Base Block Diagrams for Devices without a Secondary Master Time Base
Figure 43-11: Independent Time Base Block Diagrams for Devices with a Secondary Master Time Base
In Independent Time Base mode, each PWM generator can operate in:
• A shared time base for both the primary (PWMxH) and secondary (PWMxL) outputs
This operation occurs during Complementary, Redundant or Push-Pull mode. The
independent time base periods for both PWM outputs (PWMxH and PWMxL) are provided
by the value in the PHASEx register.
• A dedicated time base for each of the primary (PWMxH) and secondary (PWMxL) outputs
This operation occurs only during Independent Output mode. The independent time base
period for PWMxH output is provided by the value in the PHASEx register. The independent
time base period for PWMxL output is provided by the value in the PWM Secondary Phase
Shift register (SPHASEx).
PTMRx
PTPER
Equality Comparator
CLK
>
Reset
16
16
MUX
PHASEx
ITB
0
1
15 0 15
0
15
0
STMRx
PTPER
Equality Comparator
CLK
>
Reset
16
16
MUX
SPHASEx
ITB
0
1
15 0 15
0
15
0
ITB = 1
, Controls PWMxH only
ITB = 1, Controls PWMxL only
ITB = 0, Controls PWMxH and PWMxL ITB = 0, Not applicable
PTMRx
PTPER/STPER
Equality Comparator
CLK
>
Reset
16
16
MUX
PHASEx
ITBx
0
1
15 0 15
0
15
0
STMRx
Equality Comparator
CLK
>
Reset
16
16
MUX
SPHASEx
ITBx
0
1
15 0 15
0
15
0
ITB = 1
, Controls PWMxH only
ITB = 1
, Controls PWMxL only
ITB = 0, Controls PWMxH and PWMxL ITB = 0, Not applicable
PTPER/STPER
Note: The PTMRx and STMRx values are not readable to the user-assigned application.