PERFEZIONAMENTO NEI DISPOSITIVI MISURATORI DI PRESSIONE UTILIZZANTI ESTENSIMETRI

摘要

The disclosure describes circuitry for obtaining a pressure measurement from two strain gauge resistors mounted on a diaphragm which moves in response to changes in pressure. Operational amplifiers produce constant current flow through the resistors. A difference amplifier produces a measurement voltage corresponding to the difference in voltage across the resistors due to pressure variations. A unique positive feedback circuit is used in connection with the operational amplifiers to linearize the measurement voltage with respect to pressure changes. Temperature correction circuitry is used to maintain a constant measurement voltage scale over a wide range of temperature.