Patent ID: 8742708

Claim:
An electric power conversion apparatus for a vehicle having an electric motor as an electric actuator of an in-vehicle device, the apparatus comprising: an electric power conversion circuit; and a power transistor having a gate terminal, a source terminal and a drain terminal and connecting an output terminal of the electric power conversion circuit and a motor terminal of the electric motor through the source terminal and the drain terminal, the power transistor including a gate, a drain and a source of a semiconductor chip and having the source terminal positioned between the gate terminal and the drain terminal, wherein: the gate terminal, the drain terminal and the source terminal are connected to the gate, the drain and the source of the semiconductor chip, respectively; the drain terminal of the power transistor is connected to the motor terminal of the electric motor; and the semiconductor chip is a vertical-type, which has the source and the gate on one surface thereof and the drain on another surface opposite to the one surface; the drain terminal has one part, which is on the another surface and in a rectangular shape larger than the another surface in area size, and another part, which extends from one of four corners of the rectangular shape in parallel to the gate terminal and the source terminal; and the source terminal is shorter than the another part of the drain terminal.