Hello! I'm using the peak detector circuit found here along with an LM358N op amp, a 10 uF capacitor, and an 1N4148 diode. It works absolutely fine for one of the two inputs I need it to:
4 V -----------------------------------
-------------|--------|-----------------
0 V ------------------------------------
It's a positive rectangular pulse, a couple hundred microseconds long. No problem. It takes a few hits of the input for the output to reach the peak (4 V), but that's fine.
However, when I try it with a bipolar input (see below) of about the same length, the output just climbs and climbsfar higher than the peak value.
2 V -----------------------------------
-------------|-\-------------------------
0 V -------------\--------------------
-------------|----\-|-----------------
-2 V ----------------------------------
Any ideas why this second input might drive the output so high? (Again, it's just fine if it takes a few of these short inputs to get the output up to the peak valuein this case 2V.) Thanks for reading!
4 V -----------------------------------
-------------|--------|-----------------
0 V ------------------------------------
It's a positive rectangular pulse, a couple hundred microseconds long. No problem. It takes a few hits of the input for the output to reach the peak (4 V), but that's fine.
However, when I try it with a bipolar input (see below) of about the same length, the output just climbs and climbsfar higher than the peak value.
2 V -----------------------------------
-------------|-\-------------------------
0 V -------------\--------------------
-------------|----\-|-----------------
-2 V ----------------------------------
Any ideas why this second input might drive the output so high? (Again, it's just fine if it takes a few of these short inputs to get the output up to the peak valuein this case 2V.) Thanks for reading!