STRUCTURAL ARRANGEMENT FOR DRIVE CIRCUIT

A shortest distance (d) between a drive circuit (4) and an electric wire (8b) is set such that an electric field caused by an electric current flowing in the electric wire (8b) that electrically connects an ignition-voltage generating device (IG) and an ignition plug (6) induces a surge voltage to the drive circuit (4) via an electrostatic capacity (Cm) between the drive circuit (4) that can freely inject fuel from a fuel injection device (7) provided in an internal-combustion engine (5) to the internal-combustion engine (5) under control of a microcomputer and the electric wire (8b), and the surge voltage becomes equal to or lower than predetermined surge withstanding capability of the semiconductor power device.