To provide a power supply controller wherein the output of a power supply unit is stopped, without adding new circuits in combined electronic equipment and power-on/off operation on a device-by-device basis is made unnecessary.

The power supply controller for compound electronic equipment is constituted such that the control signals are inputted from a main unit CPU 10 to voltage conversion circuits 31, 32, and 33 which supply different levels of voltages to corresponding functional blocks, and thereby voltage supply is controlled; voltage conversion circuits for supplying voltages of the levels, corresponding to functional blocks which are out of use, are turned off; and thereby the power consumption is reduced.