Ignition device and ignition system

An ignition device for an internal combustion engine comprising:

• a main ignition circuit to generate a spark discharge to a spark plug by controlling energization of a primary coil of an ignition coil;
• an energy supply circuit that continues a spark discharge started by an operation of the main ignition circuit by controlling the energization of the primary coil during the spark discharge started by the operation of the main ignition circuit to supply a secondary current in the same direction as a main ignition continuously in a secondary coil of the ignition coil;
• a feedback circuit that detects the secondary current and feeds back the secondary current to the energy supply circuit;
• and
• a secondary current control circuit that receives a secondary current control signal indicating a control value of the secondary current from a separate control unit, wherein,
• the control value of the secondary current is obtained in accordance with engine parameters indicating an operating condition of the internal combustion engine;
• and
• the feedback circuit outputs the control signal for controlling the energization of the primary coil to the energy supply circuit according to a result of comparison between the control value of the secondary current outputted from the secondary current control circuit and a detected value of the secondary current.