I have a DC / DC converter in the + -12V output connected to the comparator's power pins. A square wave of 1 kHz is applied to one of the inputs of the comparator.
The output of the comparator should be in the form of a square wave, oscillating in the range of + -12V.
When connecting the multimeter to the output of the comparator, I see a value of -12V. When I switch to the frequency measurement mode, I see 999.6Hz, which approximately approaches 1kHz.
It’s not very clear to me how a multimeter can measure the voltage of a PWM signal. Why does he give out exactly negative voltage? Does he make a specific selection?