| 摘要 |
PROBLEM TO BE SOLVED: To detect a contact state of a terminal with a measuring target while minimizing cost rise. SOLUTION: A voltage measurement part 5 includes: an operational amplifier 21a of which the non-inverting input terminal is connected to a voltage detection terminal Hp and connected also to reference potential through a resistor 21b to amplify the voltage of the voltage detection terminal Hp and output the amplified voltage as a voltage signal V4; an operational amplifier 22a of which the non-inverting input terminal is connected to a voltage detection terminal Lp and connected also to the reference potential through a resistor 22b to amplify the voltage of the voltage detection terminal Lp and output the amplified voltage as a voltage signal V5; and a voltage detection circuit 23 for outputting a differential voltage between respective signals V4, V5 as a voltage signal V6. Respective resistors 21b, 22b are regulated to resistance values capable of saturating respective signals V4, V5 when input bias currents of the operational amplifiers 21a, 22a are allowed to flow. A processing part 6 discriminates contact states of respective terminals Hc, Lc, Hp, Lp with a measuring target 2 based on a current value of an inspection current I1 measured by a current measurement part 4 and the voltage value of the voltage signal V6. COPYRIGHT: (C)2012,JPO&INPIT |
