This paper presents a high accuracy miniature absolute pressure transducer suitable for use in flight test environments. High transducer accuracy was achieved by using a highly sensitive piezoresistive pressure sensor in conjunction with high resolution digital electronics for sensor output amplification and correction. The transducer size was minimized for reducing air flow disturbance and for ease of installation. The pressure sensor chip has a Silicon-on-Insulator structure with piezoresistors dielectrically isolated from the deflecting diaphragm. Optimal pressure sensor geometry for low pressure (5-50 PSI) measurements was determined through Finite Element Modeling. The sensor output was corrected for temperature variations using a commercially available digital integrated circuit and a novel algorithm for computing temperature compensation coefficients. The optimized pressure transducer has an accuracy of 0.1percent of full scale output at temperatures up to 250 deg F. The transducer has a volume of less than 0.2 cubic inches, and a bandwidth of over 10 kHz. Independent testing has confirmed that this transducer is a good fit for the flight test environment as well as for other applications requiring high accuracies over wide temperature ranges (-65 deg F - 250 deg F).
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