Patent ID: 6848437

Claim:
An ignition device for an internal combustion engine in which a power source is connected to one end of a primary winding of an ignition coil mounted to said internal combustion engine, an ignition plug is connected to one end of a secondary winding of said ignition coil and the current flow through said primary winding is cut off to supply a high voltage generated through said secondary winding to said ignition plug, said ignition device comprising: control means for outputting an ignition signal used to determine a time when an ignition plug should be ignited; switching means connected to the other terminal of a primary coil for cutting off the flow of a primary current; drive means for turning ON or OFF the switching means in response to the ignition signal to adjust a voltage to be applied to a gate of the switching means; and filter means, external to the drive means, for absorbing a surge generated in the voltage of said power source.