Ignition device of internal combustion engine

An ignition device of an internal combustion engine comprising:

• an ignition coil that generates a discharge energy at a secondary coil connected to an ignition plug, the discharge energy being generated in response to a change in a primary current flowing through a primary coil;
• a main ignition circuit that controls an energization of the primary coil so as to produce a spark discharge at the ignition coil;
• an energy input circuit that performs an energy input operation for superposing a current having the same polarity to a secondary current flowing through the secondary coil;
• and
• a signal generation circuit that generates, based on a main ignition signal that controls the main ignition operation, at least one of an energy input signal controlling the energy input operation and a target secondary current command signal commanding a target secondary current value, wherein
• the signal generation circuit includes an operation region determination unit that determines an operation region of an internal combustion engine;
• and
• the ignition device determines whether an energy input operation is performed in accordance with a determination result of the operation region determination unit.