my square wave output consisit of a few spike occasionally. anyway to remove the spike/noise ?

 

my square wave output consisit of a few spike occasionally. anyway to remove the spike/noise ?

Use a zener diode and a resistor in a series combination and then in parallel with a small capacitor to absorb the spikes. The diode should turn on fast and the capacitor should have low lead inductance. Also, the RC charging time of the capacitor should be slightly more than the turn on time of the diode as not to be charged at the spike's voltage before the diode turns on.

Note that the capacitor may affect the shape of the pulses a bit.

 

Well, a possible solution would be to eliminate the peak at it's source, if possible. Why is it being generated?

A low pass filter can remove the spikes, but would smooth the square wave, also. That said, it's maybe not a problem to slightly smooth the signal.

You could use a schmitt trigger gate to restore the signal beautiness. If the spikes won't make the gate to falsely trigger, it can be used alone, or you could need to use the low pass filter, or a combination of both.