PROBLEM TO BE SOLVED: To enhance responsibility after measuring internal resistance, by enabling normal operation to possible quickly after the measurement of internal resistance. SOLUTION: The circuit is composed, such that the bias voltage VCC outputted from a measuring biased power source VCC is impressed to a sensor 10 via a first switch SW1, after measuring of the internal resistance of the sensor, based on the output voltage VM of sensor 10 measured with an amplifier AMP, grounding potential or negative potential is impressed to the sensor 10 via a second switch SW2 and then the outputs of sensor 10 is forced to shift in reverse from a reverse-bias status to the direction of forward bias. COPYRIGHT: (C)2005,JPO&NCIPI
