Further Improvements Relating to the Temperature Compensation of Semiconductor Strain Gauge Pressure Transducers

摘要

Two methods by which the passively compensated thermal offset and sensitivity stability of commercial semiconductor strain gage pressure transducers may be improved by 1 order of magnitude in the temperature range minus 160 to plus 100 C are described. The first method, using active analog compensation circuitry is easy to use and may be applied retrospectively to any strain gage device operating on a four-arm Wheatstone bridge principle. The process operates independently of existing signal conditioning amplifiers, being self-contained to the transducer and its excitation supply only. A second method by which the raw transducer outputs may be equally compensated using a real-time digital process is described. A feature incorporated into the circuitry enables the transducer to measure pressure and temperature simultaneously at no extra cost or complexity to manufacturer or user.