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2.6.4.1
One-Shot Pulse
PSCLK
OSHT
EPWMxA in
EPWMxA out
Prog. pulse width
(OSHTWTH)
(OSHTWTH)
Start OSHT pulse
Sustaining pulses
PWM-Chopper (PC) Submodule
The width of the first pulse can be programmed to any of 16 possible pulse width values. The width or
period of the first pulse is given by:
period of the first pulse is given by:
T
1stpulse
= T
SYSCLKOUT
×
8
×
OSHTWTH
Where T
SYSCLKOUT
is the period of the system clock (SYSCLKOUT) and OSHTWTH is the four control bits
(value from 1 to 16)
shows the first and subsequent sustaining pulses and Table 7.3 gives the possible pulse width
values for a SYSCLKOUT = 100 MHz.
Figure 2-33. PWM-Chopper Submodule Waveforms Showing the First Pulse and Subsequent Sustaining
Pulses
Table 2-16. Possible Pulse Width Values for
SYSCLKOUT = 100 MHz
OSHTWTHz
Pulse Width
(hex)
(nS)
0
80
1
160
2
240
3
320
4
400
5
480
6
560
7
640
8
720
9
800
A
880
B
960
C
1040
D
1120
E
1200
F
1280
SPRU791D – November 2004 – Revised October 2007
ePWM Submodules
57