Datasheet

Preliminary Technical Data Eval–ADM8843
13 REV. PrC 02/05
ADuC832 PWM
The ADuC832 is operated in single variable resolution PWM (Mode 1), in this mode the pulse length and the cycle time (period) are
programmable in user code, allowing the resolution of the PWM to be variable.
PWM1H/L sets the period of the output waveform. Reducing PWM1H/L reduces the resolution of the PWM output but increases the
maximum output rate of the PWM. (e.g., setting PWM1H/L to 65536 gives a 16-bit PWM with a maximum output rate of 266Hz
(16.777MHz/65536), because the maximum output rate is 266Hz and the ADM8843 PWM brightness control requires the output to go as
low as 100Hz we have to use a lower frequency clock (32kHz) to generate the lower frequencies below 256Hz.
Setting PWM1H/L to 4096 gives a 12-bit PWM with a maximum output rate of 4096Hz (16.777MHz/4096).
PWH0H/L sets the duty cycle of the PWM output waveform, as shown on Figure 2.
Figure 12. ADuC832 PWM in Mode 1