SCHMIDT TRIGGER CIRCUIT OPERATING ACCORDING TO PULSE WIDTH

PROBLEM TO BE SOLVED: To provide a Schmidt trigger circuit with a hysteresis characteristic in which the release point and the operation point are determined based on the width of an input pulse.SOLUTION: The Schmidt trigger circuit comprises: a signal/pulse switch part for, upon the receipt of an analog signal, generating an input pulse with a width corresponding to the size of the analog signal; a pulse width determination part for comparing the width of the input pulse generated in the signal/pulse switch part with a predetermined first threshold width and a predetermined second threshold width larger than the first threshold width, and outputting state information representing the result; and an output determination part for, based on the state information, outputting a high signal when the width of the input pulse is changed from a state in which the width is smaller than the second threshold width to a state in which the width is larger than the second threshold width and outputting a low signal when the width of the input pulse is changed from a state in which the width is smaller than the first threshold width to a state in which the width is larger than the first threshold width.