Patent ID: 8658300

Claim:
A fuel gauge system for detecting a residual quantity of a battery, comprising: a substrate having a positive power-supply terminal; a protection circuit disposed on the substrate, the protection circuit protecting charging and discharging of the battery, and having a voltage monitor terminal; and a fuel gauge circuit disposed on the substrate, comprising: a voltage sensor; a voltage monitor terminal disposed on a side of the fuel gauge circuit, facing the positive power-supply terminal of the substrate, and connected to each of the positive power-supply terminal of the substrate and the voltage sensor disposed in the fuel gauge circuit; a voltage through terminal disposed on a side of the fuel gauge circuit, facing the protection circuit and being opposite to the side facing the positive power-supply terminal, and connected to the voltage monitor terminal of the protection circuit; and a wiring disposed within the fuel gauge circuit to connect the voltage monitor terminal of the fuel gauge circuit to the voltage through terminal.