Control device and electric power steering apparatus

A control device for controlling an operation of an electric motor, which is rotated when the electric motor is powered by electric power supplied from an electric power source, the control device comprising:

• an electric power converter that includes a plurality of switching elements, wherein the electric power converter converts the electric power supplied from the electric power source and supplies the converted electric power to the electric motor;
• a controller that is operated by the electric power supplied from the electric power source and controls an operation of the electric power converter;
• and
• a booster that is operable to boost a voltage of the electric power inputted from the electric power source and to output the boosted electric power source voltage to the controller, wherein the controller includes:
• a microcomputer that is configured to output a control signal, which is used to control the operation of the electric power converter;
• and
• a boost circuit that is provided separately from the booster and is operable to boost the voltage of the electric power inputted from the electric power source and to output the boosted electric power source voltage of the boost circuit to the electric power converter;
• the booster is operable to output the boosted electric power source voltage to the controller to power the microcomputer and to the boost circuit;
• and
• the boost circuit is further operable to boost the boosted electric power source voltage inputted from the booster to the controller and to output the boosted voltage to the electric power converter.