アナログ手法による半導体ひずみゲージブリッジの高精度温度補償法

抄録

Bridge of semiconductor strain gauges with a silicon diaphragm is very useful for pressure measurement and has currently wide applications for many fields. However, these gauges have miss matchings of resistance and temperature co-efficients. These facts bring difficulties for use in a wide temperature range with high accuracy.
This paper presents the precision and wide range temperature compensation algorithm for semicoductor strain gauge bridge by the analogue circuit technique.
The compensation by an analogue circuit can achieve its purpose with small size of hardware and can produce higher reliabilitiy and lower cost than digital methods. One of the subjects of temperature compensation is to take balance of bridge at several temperature points. The others are to keep sensitivity at constant value against the third order non-linear temperature co-efficients and to eliminate the interference between balance adjustment and balance compensation. These subjects have been achieved without measuring temperature itself.
This temperature compensation method is implemented with good temperature stabilities to mass-produced pressure and differential pressure transmitters of a silicon diaphragm type sensor for industrial use.