Patent ID: 8006678

Claim:
An igniter system comprising: an ignition coil; a switching element for turning on and off a current flowing through the ignition coil; and a control circuit for the switching element, the control circuit comprising: a current detecting device that detects a current flowing through the switching element; a measuring device that measures a length of a period from a time point when the current flowing through the switching element that is increasing exceeds a first current setting value to a time point when it reaches a second current setting value that is larger than the first current setting value; a judgment circuit for judging whether the measured length of the period is either shorter than a preset lower limit reference length or longer than a preset upper limit reference length; and an output device that outputs a signal for turning off the switching element if the judgment circuit judges that the measured length of the period is shorter than the lower limit reference length or longer than the upper limit reference length.