The following equation and calculator gives values for Schmitt Trigger and an Inverting Schmitt Trigger.
A Schmitt trigger is a A multivibrator that produces
uniform-amplitude output pulses from a variable
amplitude input signal. This circuit has
many applications, one being the conversion of a
sine wave into a square wave.
Schmitt trigger circuits are used as signal conditioning to remove noise from signals used in digital circuits, particularly mechanical switch bounce. They are also used in closed loop negative feedback configurations to implement relaxation oscillators, used in function generators and switching power supplies.