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What's the difference between PPG and PWM output?

Latest Updated:04/01/2006

Question:

The timer output function includes PPG and PWM output.
Both output similar signals, so I do not really understand the difference.

Answer:

PPG output is a function for outputting a pulse whose cycle and width is specified.
In this function, the issue is the waveform itself (timing).
Therefore, changes in parameters (pulse cycle and width) are reflected immediately.
Consequently, depending on the timing of the change, the output may be inverted.
In PWM output, the pulse is output as specifying an active period in the specified cycle so as to output analog amount.
In this function, the issue is the proportion of active period in the specified cycle rather than the waveform itself.
Consequently, some microcontrollers have a function to output the active period divided into multiple sections.
Also, in the PWM output function, regardless of the timing at which the parameter (cycle, active period, etc.) was changed, the change is only reflected at the end of one cycle, so the output does not become abnormal.
On the other hand, even if the parameter is changed, that change is not immediately reflected in the operation.
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