Electric Driving Device and Electric Power Steering Device

An electric power steering device constructed by an electric motor for applying a steering assist force to a steering shaft and an electronic control unit located opposite to an output shaft of the electric motor and configured to control the electric motor, the electronic control unit being equipped with an ECU housing connected to a motor housing in which the electric motor is housed and an electronic control assembly housed in the ECU housing for driving and controlling the electric motor, wherein

• the electronic control assembly is divided into a power-supply circuit unit having a main function that generates a power supply and mounted on a metal substrate, a power-conversion circuit unit having a main function that drives the electric motor and mounted on a metal substrate, and a control circuit unit having a main function that controls the power-conversion circuit unit and mounted on a resin substrate, in that at least a power-supply-connector wiring part that supplies electric power from the power-supply circuit unit to the power-conversion circuit unit and the control circuit unit and a signal-transmission-connector wiring part that transmits signals to be input to or output from the control circuit unit are embedded in a connector terminal assembly made of synthetic resin, and that connector terminals of the power-supply-connector wiring part and the signal-transmission-connector wiring part, which are exposed from the connector terminal assembly, are directly connected to corresponding connectors of the power-supply circuit unit, the power-conversion circuit unit, and the control circuit unit.