Motor Speed control Waveforms |
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Trace 1 :- This goes hi every time the ADC is sampling |
| Trace 2 :- Goes low when the PWM is gated OFF. | ||
Trace 3 :- The PWM Pulses. |
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| Trace 4 :- The voltage across the motor after filtering. | ||
| The ADC samples channels 0-3 in a continuouse sequence except when sampling the motor feed back voltage Channel 4 this is the group of 8 samples taken 1mS after the start of the PWM off period. these 8 sample are averaged. The delay of 1mS before ADC sampling is to allow the motor inductive circulating current to die away. | ||