Electrical – How to stabilize the output square wave of a TL074CN (Comparator)

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Figure 1


simulate this circuit – Schematic created using CircuitLab

I am using a TL074CN comparator to compare a fullwave rectified input voltage with a DC voltage of 1.4 V as shown in the above figure. At the output of the comparator, I am receiving a square wave which goes from +12V to -12V.

Figure 2

enter image description here

The figure 2 above shows the square wave generated in microsecond level. As you can see the waveform is very unstable at the moment. So far what I tried was

1) I also added a 100u capacitor at the output of the opmamp but it doesn't stabilize the waveform , it instead curves the waveform at the edges

2) I added a 10K resistor at the output but it doesn't help either.

3) I switched the TL074CN with an LM324N and still did not stabilize the waveform

Is there anything which I can do to make this square wave stable?

Best Answer

The TL074 and LM324 are op-amps, not comparators.

If you want a device to operate as a comparator, you should use something designed for that application, like an LM319.