Power supply circuit

摘要

A power supply circuit capable of reducing the power consumption during the standby state of an electric appliance. The power supply circuit for supplying the electric appliance with voltages to drive and control the electric appliance, includes a controller for controlling the operation of the electric appliance, a DC-DC converter for outputting a fixed voltage V1 and a variable voltage V2, and a regulator for converting the fixed voltage V1 derived from the DC-DC converter into a specified voltage and supplying the specified voltage to the controller 16 for the electric appliance. The DC-DC converter identifies the state of the air conditioner. When the electric appliance is identified to be in the standby state, the DC-DC converter reduces the fixed voltage V1, which is inputted to the regulator to a voltage lower than a voltage outputted in the operative state.