In an internal combustion engine use ignition device includes an ignition coil which has a primary coil and a secondary coil, that are wound around a core, a superimpose circuit which generates an output energy, that is to be superimposed with respect to a secondary current, produced in the secondary coil by the primary coil, a first switch element which is connected to the primary coil and turns on or off of a current to the primary coil, a second switch element which is connected to the superimpose circuit, and stops an operation in a case where the first switch element is turned on, and performs an operation in a case where the first switch element is turned off, and a common input terminal which receives a first driving signal for driving the first switch element and a second driving signal for driving the second switch element.

An ignition control system performs discharge generation control, in which a discharge spark is generated, once or a plurality of times during a single combustion cycle. The ignition control system successively calculates an approximate energy density based on a secondary current and a discharge path length. During a predetermined period after blocking of a primary current is performed during a single combustion cycle, the ignition control system calculates an integrated value by integrating the discharge path length at this time, based on the approximate energy density being greater than a predetermined value. The ignition control system performs the discharge generation control again based on the calculated integrated value being less than a first threshold.

Provided is an internal combustion engine ignition device capable of preventing an output signal level of a drive circuit from changing sharply when shifting from a normal ignition operation mode to a protection operation mode while reducing the cost of dedicated components and the like. An internal combustion engine ignition device of the present invention includes a first differential circuit for outputting a drive signal in a first mode and a second differential circuit for outputting a drive signal in a second mode, where the first differential circuit and the second differential circuit each include a transistor and are configured such that a drive current for supplying the drive signal flows through the transistor which is common between the first mode and the second mode.

A spark plug heat up method via transient control of the spark discharge current. The high temperature plasma channel is used to heat up the central electrode, and the temperature and energy of the plasma channel are realized via transient control of the discharge current. The heating up process takes place before firing the engine, using discharge current to actively heat up the spark plug from inside. By monitoring the discharge current amplitude and discharge duration, the temperature change of the central electrode and the ceramic insulator can be carefully measured and controlled within a proper window. This method can be used to measure the heating range of the spark plug, and to prevent or remove the carbon deposit on the central electrode and the ceramic insulator generated under various engine operation conditions, such as engine cold start, full load operation, and heavy EGR condition, as well as realize self-cleaning.

In an ignition control device for an internal-combustion engine, signal separation circuitry receives and separates an ignition control signal that is an integrated signal of 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 command signal. The ignition control signal is formed of a first signal and a second signal that are pulsed signals. The signal separation circuitry is configured to generate, from the ignition control signal, the main ignition signal based on rising edges of the first signal and the second signal as pulse-waveform information of the first signal and the second signal, generate the energy input signal based on a pulse width of the second signal as pulse-waveform information of the second signal, and generate the target secondary current command signal based on pulse-waveform information of the first signal.

A current control circuit for an ignition system (i.e., igniter current limiter) is disclosed. The current control circuit can reduce a coil current over a soft shut down (SSD) period using an insulated gate bipolar transistor (IGBT) that is controlled by a negative feedback loop, which controls the current limit of the IGBT according to a SSD profile. In order to prevent an unwanted current rise during the soft shut down period, the current control circuit compares a gate voltage of the IGBT to a reference signal and based on the comparison can enable the SSD profile to include a fast ramp. The fast ramp quickly lowers the current limit of the IGBT so that the coil current equals the current limit and can be controlled by the negative feedback loop.

A multi-charge ignition system including a spark plug control unit (13) adapted to control at least two coil stages so as to successively energise and de-energise said coil stage(s) to provide a current to a spark plug, said two stages comprising a first transformer (T1) including a first primary winding (L1) inductively coupled to a first secondary winding (L2); a second transformer (T2) including a second primary winding (L3) inductively coupled to a second secondary winding (L4); a first switch Q1 electrically connected between the low side of the first primary winding L1 and the low side/earth, a second switch Q2 having a connection to the low side of the second primary winding L3; and including a first diode D1 electrically connected between the low side of said first secondary winding L3 and ground, and a second diode D2 connected to a point between the low side of said second secondary winding L4 and ground and, including means to measure the voltage at a first connection point (203a) between the first switch and the low side of L1 and/or the voltage at a second connection (203b) point between the second switch and the low side of L3; and means to control the operation of the system dependent upon said measured voltages.

In an internal combustion engine use ignition device includes an ignition coil which has a primary coil and a secondary coil, that are wound around a core, a superimpose circuit which generates an output energy, that is to be superimposed with respect to a secondary current, produced in the secondary coil by the primary coil, a first switch element which is connected to the primary coil and turns on or off of a current to the primary coil, a second switch element which is connected to the superimpose circuit, and stops an operation in a case where the first switch element is turned on, and performs an operation in a case where the first switch element is turned off, and a common input terminal which receives a first driving signal for driving the first switch element and a second driving signal for driving the second switch element.

Disclosed is an ignition drive module with stable performance and reliable function, which comprises a module signal input end, a voltage input end, a module signal output end, a comparator. One end of the comparator is connected to the module signal input end, and the other end is connected to a comparison resistance R that is grounded. The ignition drive module further comprises a maximum dwell timer module connected to the comparator, a logical judgment module connected to the comparator, and an IGBT module connected to the logical judgment module which receives the signals from the maximum dwell timer module and the comparator to determine whether to activate the IGBT module. The output end of the IGBT module is connected to the module signal output end.

An internal combustion engine ignition device includes an ignition coil, an ignition plug, a main ignition circuit, and an energy input circuit. A first switching element of the main ignition circuit performs energization and interruption of energization to a first coil part of a primary coil to generate an induced electromotive force using a DC voltage. A second switching element of the energy input circuit performs energization and interruption of energization to a second coil part of the primary coil to keep a discharge current in a secondary coil within an intended range directly using the DC voltage, after the induced electromotive force has been generated. A soft-off circuit of the energy input circuit slows a turn-off speed of the second switching element. The energy input circuit is configured to, when decreasing a signal voltage added to a gate of the second switching element, execute a first decreasing stage of decreasing the signal voltage until it reaches the vicinity of a gate-source threshold voltage and a second decreasing stage of gradually decreasing the signal voltage in the vicinity of the threshold voltage.