Ignition control device

An ignition control device comprising:

• an ignition coil which generates discharge energy in a secondary coil connected to a spark plug by increasing and decreasing a primary current flowing through a primary coil;
• a main ignition circuit unit which controls energization of the primary coil to perform a main ignition operation for causing the spark plug to generate a spark discharge;
• and
• an energy input circuit unit which performs an energy input operation for superimposing a current of the same polarity on a secondary current caused to flow through the secondary coil by the main ignition operation,
• wherein the ignition control device further comprises a signal separation circuit unit which receives an ignition control signal which is a signal combining a main ignition signal for controlling the main ignition operation, an energy input signal for controlling the energy input operation, and a target secondary current instruction signal, and separates one or more signals included in the received ignition control signal,
• the ignition control signal includes a first pulse signal and a second pulse signal, and is transmitted prior to the main ignition operation,
• the signal separation circuit unit includes a main ignition signal generation circuit which generates the main ignition signal such that a point in time when a waiting time has passed from a detection start time of the first pulse signal at which a signal level of the ignition control signal changed from a first level to a second level for the first time, and the signal level of the ignition control signal is the second level, is a start of the main ignition signal, and a detection end time of the second pulse signal at which the signal level of the ignition control signal shifts to the first level thereafter is an end of the main ignition signal, and
• the main ignition circuit unit energizes the primary coil at the start of the main ignition signal and cuts off the energization of the primary coil at the end of the main ignition signal.