Patent ID: 8957665
Filing Date: 2015-02-17
Classification: G01R

Abstract:
1. A voltage measurement apparatus for detecting plural voltage measurement points of a voltage measurement object by using a voltage measurement circuit, the apparatus comprising: a switch circuit coupled between each of the plural voltage measurement points and the voltage measurement circuit, the switch circuit is turned on and off by an electric current flowing in a current carrying part of the switch circuit; a power supply side constant current circuit coupled to a power supply side; a ground side constant current circuit coupled to a ground side to draw a constant current that is similar to a constant current provided by the power supply side constant current circuit; a control circuit that controls the operation of the power supply side constant current circuit and the ground side constant current circuit, wherein the current carrying part of the switch circuit is coupled to a constant current path that allows the constant current to flow between the power supply side constant current circuit and the ground side constant current circuit, and the current carrying part turns the switch circuit on and off through the control circuit.