I have almost finished a project that was supposed to output a square wave signal with a certain frequency but when I tried to make a small change to the circuit something weird happened to my output.
Here is the circuit with +-5 V power supplies:
As you can see at the very end of each pulse a small distortion appears when I am using a Zener diode as a reference.
Before I was using a transistor that functioned as a diode and my output was still not perfect, but better.
Why does the output spike like this when I change the reference to a diode and also changed the values of the bias resistors? A better question, how can I minimize these spikes overall?
P.S I've tried playing with the Miller capacitor but 47pF was the sweet spot.