| 摘要 |
<p>A circuit for measuring a parameter to be sensed by means of at least one variable impedance sensor responsive to such parameter. The circuit includes a frequency determining means coupled to the variable sensor for providing an oscillatory frequency signal responsive to the impedance of the sensor, a signal amplifier coupled to the frequency determining means for amplifying the frequency signal to provide an output signal representative of the frequency signal and to sustain circuit oscillation, a signal detector coupled to the output signal to provide a control signal representative of such output signal, and a control coupled to receive the control signal and coupled to the frequency determining means thus allowing the oscillatory frequency signal of the circuit to oscillate at a frequency representative of the measured parameter.</p> |
