Power supply equipped with battery unit

Abstract

A fuse element of a SCP is reliably fusion-cut with a simple circuit configuration to interrupt an electric current. In a power supply equipped with a battery unit, a control circuit () is configured to control turning on and off of a switch () configured to connect the SCP () which is connected in series to a battery unit () and is configured to interrupt charge and discharge currents in an abnormal state. Battery unitincludes battery cells () connected in series to one another. The SCP () includes fuse elementconnected in series to an output end of the battery unit (), and a heater () configured to fusion-cut the fuse element (). The switch () includes switching elements () each of which has one terminal connected to the heater () and another terminal connected to a corresponding one of different-voltage terminals () of the battery unit. In control circuit (), a selection circuit () is configured to select, according to the voltage detected by the voltage detection circuit (), a switching element () to be turned on, and the switching element () which is turned on connects the battery unit () to the heater () to fusion-cut the fuse element ().