Figure 130. Asymmetric Pwm Mode Versus Center-Aligned Counting Mode - Holtek HT32F50231 User Manual

32-Bit Arm ® Cortex ® -M0+ MCU
HT32F50231/HT32F50241
Asymmetric PWM Mode
Asymmetric PWM mode allows two center-aligned PWM signals to be genetated with a
programmable phase shift. While the PWM frequency is determined by the value of the CRR
register, the duty cycle and the phase-shift are determined by the CHxCCR and CHxACR register.
When the counter is counting up, the PWM uses the value in CHxCCR as up-count compare
value. When the counter is into the counting down stage, the PWM uses the value in CHxACR as
down-count compare value. The figure 130 is shown as an example for asymmetric PWM mode in
Center-aligned Counting mode.
Note: Asymmetric PWM mode can only be operated in Center-aligned Counting mode.
CNTR 0 1 2 3 4 5 6 7 8 7
PWM center align mode
CRR = 8
CCR = 3, ACR = X
CHxOREF
PWM center align mode
CRR = 8
CCR = 5, ACR = X
CHxOREF
Asymetric PWM center align mode
CRR = 8
CCR = 3, ACR = 5
CHxOREF
Asymetric PWM center align mode
CRR = 8
CCR = 5, ACR = 3
CHxOREF

Figure 130. Asymmetric PWM Mode versus Center-aligned Counting Mode

Rev. 1.00
6 5 4 3 2 1 0 1 2 3 4 5 6
CRR = 8
326 of 486
7 8 7 6 5 4 3 2 1 0 1 2 3
CCR = 3
CCR = 5
CCR = 3
ACR = 5
CCR = 5
ACR = 3
4 5 6 7 8 7 6 5 4 3 2 1
Phase delay =2
July 31, 2018