Patent ID: 8760168
Filing Date: 2014-06-24
Classification: B60L,G01R,Y02T

Abstract:
1. An assembled battery total voltage detection circuit for detecting a total voltage of an assembled battery configured by connecting a plurality of batteries, comprising: a main control circuit that includes an A/D converter operating with a positive single power supply; a divider resistor connected between a plus terminal and a minus terminal of the assembled battery insulated from the main control circuit; a differential amplifier circuit, including a first buffer, a second buffer and a differential amplifier, that amplifies voltage divided by the divider resistor and that outputs the amplified voltage to the A/D converter, the first buffer, the second buffer and the differential amplifier each being constituted by an operational amplifier operating with a positive single power supply; and a third buffer for applying a bias voltage to the midpoint of the divider resistor, the third buffer being constituted by an operational amplifier that operates with a positive single power supply, wherein the bias voltage is a positive constant electric potential relative to a ground of the main control circuit and is set based upon an operating voltage of the operational amplifier; the amplified voltage output from the differential amplifier circuit and input to the A/D converter varies within a range of the operating voltage of the operational amplifier; and the main control circuit: