Low level voltage pulse-converter

摘要

A convertor for converting an analog signal to a digital pulse comprises a switching capacitor which is charged by a differential analog signal supplied to the switching capacitor over an input circuit. The capacitor is discharged over an output circuit with the aid of a constant current supply. The charge level of the capacitor is proportional to the analog signal so that the time it takes the capacitor to discharge to a selected low charge level, is proportional to the analog signal. This time period is used by a microprocessor control to generate a digital pulse having a pulse equal to the discharge time for the capacitor. The microprocessor also selectively connects the input and output circuits to the capacitor for respectively charging and discharging the capacitor.