Table 250. Ccr Register Change Dithering Pattern In Center-Aligned Pwm Mode; Figure 305. Dithering Effect On Duty Cycle In Center-Aligned Pwm Mode - ST STM32G4 Series Reference Manual

Advanced-control timers (TIM1/TIM8/TIM20)
Table 249. CCR and ARR register change dithering pattern (continued)
LSB value
0111
1000
1001
1010
1011
1100
1101
1110
1111
The dithering mode is also available in center-aligned PWM mode (CMS bits in TIMx_CR1
register are not equal to '00'). In this case, the dithering pattern is applied over 8 consecutive
PWM periods, considering the up and down counting phases as shown in the
below.

Figure 305. Dithering effect on duty cycle in center-aligned PWM mode

Table 250

Table 250. CCR register change dithering pattern in center-aligned PWM mode

LSB
1
value
Up Dn
0000 - -
0001 +1 -
0010 +1 -
0011 +1 -
0100 +1 -
0101 +1 -
0110 +1 -
1080/2083
1 2 3 4
+1 - +1 -
+1 - +1 -
+1 +1 +1 -
+1 +1 +1 -
+1 +1 +1 -
+1 +1 +1 -
+1 +1 +1 +1
+1 +1 +1 +1
+1 +1 +1 +1
No dithering
below shows how the dithering pattern is added in center-aligned PWM mode.
2 3
Up Dn Up Dn
- - - -
- - - -
- - - -
- - +1 -
- - +1 -
+1 - +1 -
+1 - +1 -
PWM period
5 6 7 8
+1 - +1 - +1
+1 - +1 - +1
+1 - +1 - +1
+1 - +1 - +1
+1 +1 +1 - +1
+1 +1 +1 - +1
+1 +1 +1 - +1
+1 +1 +1 - +1
+1 +1 +1 +1 +1
Dithering up
PWM period
4 5
Up Dn Up Dn
- - - -
- - - -
- - +1 -
- - +1 -
- - +1 -
- - +1 -
- - +1 -
RM0440 Rev 1
9 10 11 12 13
- +1 - +1
- +1 - +1
- +1 - +1
+1 +1 - +1
+1 +1 - +1
+1 +1 - +1
+1 +1 - +1
+1 +1 +1 +1
+1 +1 +1 +1
Dithering down
6 7
Up Dn Up Dn
- - -
- - -
- - -
- - -
- - +1
- - +1
+1 - +1
RM0440
14 15 16
- - -
- +1 -
- +1 -
- +1 -
- +1 -
+1 +1 -
+1 +1 -
+1 +1 -
+1 +1 -
Figure 305
MSv50904V1
8
Up Dn
- - -
- - -
- - -
- - -
- - -
- - -
- - -