Mounting substrate and driving device using same

摘要

A driving device for a motor has a mounting substrate (30) mounted to a base substrate (21). Highly heat-generating components such as a switching element for PWM control are mounted to the mounting substrate and only less heat-generating circuit components are mounted to the base substrate. The mounting substrate has a base plate part (32) made of a metallic plate material surround by a molded insulating material but includes a heat dissipating part (38a) where the insulating material is removed and the internal metallic plate material is exposed.