| 摘要 |
Pressure transducer circuitry accommodating pressure transducer variables for making pressure measurements in a living body. A microminiature piezoresistive pressure transducer has first and second variable resistive elements. The pressure transducer is characterized as having a pressure sensitivity ranging from 1.2 to 15 ohms per 1,000 ohms per 100 millimeters of mercury and a temperature characteristic greater than pressure sensitivity. Circuitry is coupled to the first and second variable resistive elements of the transducer including a known fixed resistive element. The known fixed resistive element is coupled to the first and second variable resistive elements for supplying a transducer excitation voltage through the known fixed resistive element to the first and second variable resistive elements. First and second amplifiers each having an input and an output are provided. The inputs of the first and second amplifiers are connected to the first and second variable resistive elements to measure the voltage across the first and second variable resistive elements so that the first and second amplifiers have outputs which have a pressure component and a temperature component therein. A computer receives the outputs of the first and second amplifiers and ascertains the unknown resistances of the first and second variable resistive elements as independent variable resistive elements by solving a set of equations having said first and second variable resistive elements as unknowns and pressure and temperature as the remaining unknowns to provide a temperature compensated pressure value as measured by the microminiature pressure transducer.
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