93Views4Replies

Author Options:

Reading the max voltage of a low duty cycle PWM? Answered

How do I measure the maximum voltage reached by a very low duty cycle PWM signal without having to alter the signal. The multimeter shows no reading or gives a very brief wrong reading and falls back to zero. I don't have an oscilloscope. Are there any other alternative set-ups to measure just the voltage in this case. Please suggest.

Comments

The forums are retiring in 2021 and are now closed for new topics and comments.
0
steveastrouk
steveastrouk

5 years ago

Use a diode, and pump it onto a capacitor. Measure the capacitor voltage after a few cycles, deduct 0.7V

0
mpilchfamily
mpilchfamily

5 years ago

Get a better meter that can hold on the lowest or highest voltage measured.

0
iceng
iceng

5 years ago

The max voltage is the source voltage minus one transistor forward drop.

If you are using a fet then subtract 0.3V

If you are using a Bipolar then subtract 0.6V

If you are using a darlington then subtract 1.3V