POWER SUPPLY MECHANISM OF BUS BOARD DEVICE

PURPOSE:To enable the switching control of an electric power supplied to a required circuit board to be automatically and quickly carried out by a method wherein a power supply wiring, a voltage circuit, and a power supply switching control circuit are provided as prescribed. CONSTITUTION:A bus board 1 and connectors C1 to C5, which are fixed to the bus board 1 and each provided with connector pins optional in number are provided, and circuit boards B1 and B2 are mounted on the connectors C1 to C5. The power supply mechanism of the bus board device power supply as mentioned above is equipped with power supply wirings electrically independent of each other and allotted to the connector pins of the connectors C1 to C5 in specific rows and voltage source circuits which generate prescribed voltages. Furthermore, a power supply switching control circuit which supplies the power supply voltage of a voltage source circuit to a power supply wiring designated by a switching control signal preventing the power supply voltage of the voltage source circuit from being supplied to a power supply wiring not designated by control signals is provided.