| 摘要 |
A strain gauge pressure transducer apparatus having an impedance bridge of strain gauges formed on a thin wall semiconductor diaphragm to which a pressure to be detected is applied. Each of two arms of the impedance bridge includes two series-connected pressure transducer elements of the semiconductor strain gauges, and is electrically connected at one end thereof to each other. An operational amplifier of an excitation source supplies the impedance bridge with excitation current. That is, the output of the operational amplifier is connected to the junction of the two arms of the impedance bridge, and the inverting input thereof to the other end of one of the two arms. To the non-inverting input of the operational amplifier, a voltage signal varying in accordance with the changing of an ambient temperature is applied. Intermediate nodes of the two arms of the impedance bridge are connected to the inverting and non-inverting inputs of another operational amplifier, respectively. The output of the another operational amplifier is fed back to the other end of the other arm of the impedance bridge. |
