GD32VF103 User Manual
241
Dead time insertion
The dead time insertion is enabled when both CHxEN and CHxNEN are configured to 1
’
b1,
it is also necessary to configure POEN to 1. The field named DTCFG defines the dead time
delay that can be used for all channels except channel 3. Refer to the TIMERx_CCHP register
for details about the delay time.
The dead time delay insertion ensures that two complementary signals are not active at the
same time.
When the channelx match event (TIMERx counter = CHxVAL) occurs, OxCPRE will be
toggled in PWM mode 0. At point A in
Figure 15-18. Complementary output with dead time
CHx_O signal remains at the low level until the end of the dead time delay, while
CHx_ON signal will be cleared at once. Similarly, at point B when the channelx match event
(TIMERx counter = CHxVAL) occurs again, OxCPRE is cleared, and CHx_O signal will be
cleared at once, while CHx_ON signal remains at the low level until the end of the dead time
delay.
Sometimes, we can see corner cases about the dead time insertion. For example: the dead
time delay is greater than or equal to the duty cycle of the CHx_O signal, then the CHx_O
signal is always inactive. (as show in the
Figure 15-18. Complementary output with dead
Figure 15-18. Complementary output with dead time insertion
0
CHxVAL
CAR
CxOPRE
CHx_O
CHx_ON
Deadtime
Corner case Deadtime > pulse width
CHx_O
CHx_ON
Deadtime
Pulse width
Deadtime
A
B
Break function
In this function, CHx_O and CHx_ON are controlled by the POEN, IOS and ROS bits in the
TIMERx_CCHP register, ISOx and ISOxN bits in the TIMERx_CTL1 register. In any case,
CHx_O and CHx_ON signals cannot be set to active level at the same time. The break
sources are input break pin and HXTAL stuck event which is generated by Clock Monitor