A comparator circuit with a large gain of open-loop requires a small amount of noise to trigger the circuit.  If such comparators are used as zero-crossing detectors and get affected by false triggering leads to unnecessary problems. This may lead to the false indication of zero crossings of the noise signal rather than the actual signal. This unnecessary switching of levels can be avoided by using a circuit known as Schmitt trigger. This circuit was invented by the scientist in America otto H. … [Read more...]