Patent ID: 8836341

Claim:
A semiconductor circuit, comprising: a selection circuit connected to a plurality of serially-connected batteries for selecting any of the plurality of batteries, the selection circuit having first and second output terminals for respectively outputting a high potential voltage and a low potential voltage of any selected battery, the low potential voltage being lower than the high potential voltage; a difference detecting circuit having first and second input terminals that are respectively in electrical connection with the first and second output terminals of the selection circuit, the difference detecting circuit being configured to receive the high and low potential voltages via the first and second input terminals and to output a difference between the high potential voltage and the low potential voltage; a wire connecting the first output terminal of the selection circuit and the first input terminal of the difference detecting circuit; and a voltage applying unit connected to the wire via first and second nodes on the wire, the voltage applying unit including a first voltage applying unit for applying a first diagnostic voltage to the wire via the first node, and a second voltage applying unit for applying a second diagnostic voltage to the wire via the second node.