Fixed and Sliding ADC position
Difference between fixed and sliding ADC position according to phase
CH1 (yellow) = PWM1
CH2 (light blue) = PWM2 (opposite of PWM1)
CH3 (pink) = PWM3 (Phase to PWM2)
CH4 (dark blue) = ADC pin with pull-up resistor of 100K
When S/H charges, the voltage will drop, that is what you see on CH4
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