To provide a circuit unit having circuits for both high-power and low-power, which is compact in size, inexpensive to supply, and assures highly reliable operation of the accommodated devices.

A circuit unit has a circuit link 22 which is prepared by punching and bending of a metal sheet, and a housing that holds the link. The circuit link 22 contains rectangular device-pad frames 26 that are provided at positions where electronic devices 28 are to be located. A heat sink of high thermal conductivity is attached to the bottom side of each device-pad frame 26, while the bottom of the heat sink is exposed to the outside of the housing.