Hi,
I have attached two pictures about PWM. One PWM is built using LM556 and the other using LM324. My question is: Is there any difference in performance when using either the one with 556 or the one with LM324?

 

Personally, I think pmw1a is more straightforward. But I'd use an actual comparator instead of an opamp for the U1b and replace U1c with a voltage divider.

 

There are simpler PWM circuits using either one 555 or two comparators if you are interested.

 

You will be bale to get high pulse rates out of the NE555.

I am not certain but I am pretty sure that the approach using the LM324 will enable a wider range of pulse widths.

 

.........the approach using the LM324 will enable a wider range of pulse widths

Yes, that approach will go from 0% duty-cycle (fully off) to 100% duty-cycle (fully on).

 

Hi,

your question is difference, yes a lot , first you can read the IC data sheet to https://www.alldatasheet.net.
from this data of ics you can understand a lot and learn to read of the parameters, and sample circuit too.

 

Thanks everyone. I chose the one with Opamps and it worked very well.