Hiromi Tosaki

THICK FILM TEMPERATURE COMPENSATING CIRCUIT FOR SEMICONDUCTOR STRAIN GAUGES

Thick film circuits were developed for temperature compensating of semiconductor strain gauges and for connecting the gauges to amplifiers in electronic pressure and differential pressure transmitters. In each circuit, ten Au pads for Al wire bonding and thirteen Ag/Pd pads for soldering must be fabricated on a small substrate. The results of the research are shown below.

A Thick Film Hybrid IC Amplifier for Industrial Use

Electronic circuits for industrial uses must satisfy the following requirements: low sensitivity to changes in the surrounding temperature, high reliability, and small size. In the amplifier for a pressure transmitter described here, the temperature dependences of its properties, Zero point and Span, are intensively influenced by TCRs of the resistors used, and by a mismatching of the temperature dependences of the off-set voltages between the two operational amplifier IC chips. As forthe thick film resistors, it has been cleared that the DuPont 1700 series resistor pastes are the most suitable:TCRs of less than