It is disclosed an electronic device to control an ignition coil of an internal combustion engine, comprising a high-voltage switch, a driving unit, a bias circuit and an integrating circuit. The high-voltage switch is connected in series with a primary winding of a coil. The driving unit is configured to control the closing and opening of the high-voltage switch. The integrating circuit is interposed between the bias circuit and a reference voltage. The integrating circuit comprises an integrating capacitor. The integrating capacitor is configured, in the case wherein a pre-ignition of the comburent-combustible mixture in the combustion chamber during the phase of charging occurs, to pre-charge during the phase of charging energy in the primary winding and it is configured, in the case wherein the pre-ignition of the comburent-combustible mixture does not occur, to maintain the charge state substantially constant during the phase of charging energy.

An ignition system for an internal combustion engine has a power source, a transformer having first and second primary windings and a secondary winding, a connector extending from the secondary winding and adapted so as to connect with a terminal of the spark plug of the internal combustion engine, and electronic spark timing circuit cooperative with the transformer so as to activate and deactivate voltage to the first and second primary windings. The first and second primary windings are connected to the power source such that the transformer produces an alternating voltage output from the secondary winding of between 1 kHz and 100 kHz and a voltage of at least 20 kV. A forced push-pull inverter is cooperative with the electronic spark timing circuit so as to fix a frequency of voltage to the first and second primary windings.

In a general aspect, an apparatus can include an insulated-gate bipolar transistor device (IGBT), a gate driver circuit (driver) coupled with a gate terminal of the IGBT and a low-resistance switch device coupled between an emitter terminal of the IGBT and an electrical ground terminal, the low-resistance switch device being coupled with the electrical ground terminal via a resistor. The apparatus can also include a current sensing circuit coupled with the driver and a current sense signal line coupled with the current sensing circuit and a current sense node, the current sense node being disposed between the low-resistance switch device and the resistor. The apparatus can further include a control circuit configured, when the driver is off, to detect, based on a voltage on the current sense node, when a current through the resistor is above a threshold value and disable the IGBT in response to the detection.

An ignition apparatus includes a spark plug having a high voltage electrode and an external electrode facing each other across a gap and being configured to generate a spark discharge in the gap to ignite a combustible fuel mixture in a combustion chamber of an internal combustion engine, an ignition coil device configured to generate a predetermined high voltage and supply the high voltage to the high voltage electrode to form a path for the spark discharge in the gap, a high frequency power supply having a band-pass filter and being configured to supply an alternating current to the spark discharge path, and a control device configured to control operation timing of the high frequency power supply. The band-pass filter passes a frequency of from 1 MHz to 4 MHz.

An ignition control device comprises: a first switching element having a power source side terminal connected to an other end side of a primary coil and a first ground side terminal connected to a ground side; a second switching element having a second ground side terminal connected to the other end side of the primary coil; a third switching element having a third power source side terminal connected to the second power source side terminal in the second switching element, and a third ground side terminal connected to the ground side; and an energy storage coil. The energy storage coil is an inductor interposed in an electric power line connecting a non-ground side output terminal in a DC power source and the third power source side terminal in the third switching element, and stores energy from the turning on of the third switching element.

An electronic device for controlling an ignition coil of an internal combustion engine includes a high voltage switch, a driving unit and a control unit. The driving unit controls the closure of the switch during charging energy in the primary winding and the opening of the switch during transferring energy from the primary winding to a secondary winding. A current measuring circuit is connected in series to a second terminal of the secondary winding to detect current generated on the secondary winding during the charging step and generate a signal representative of the detected current. The control unit receives the signal representative of the current detected by the measuring circuit, compares a relevant value of such signal with a predefined first reference value and activates a mode for detecting a soiling of the spark plug when the relevant value of the signal exceeds said predefined first reference value.

It is disclosed an electronic device to control an ignition coil of an internal combustion engine comprising a high-voltage switch, a driving unit, a bias circuit and an integrating circuit. The high-voltage switch is connected in series with a primary winding of a coil. The driving unit is configured to control the closing and opening of the high-voltage switch. The integrating circuit is interposed between the bias circuit and a reference voltage. The integrating circuit comprises an integrating capacitor. The integrating capacitor is configured, in the case wherein a pre-ignition of the comburent-combustible mixture in the combustion chamber during the phase of charging occurs, to pre-charge during the phase of charging energy in the primary winding and it is configured, in the case wherein the pre-ignition of the comburent-combustible mixture does not occur, to maintain the charge state substantially constant during the phase of charging energy.

It is disclosed an electronic device to control an ignition coil of an internal combustion engine, comprising a high-voltage switch, a driving unit, a bias circuit and an integrating circuit. The high-voltage switch is connected in series with a primary winding of a coil. The driving unit is configured to control the closing and opening of the high-voltage switch. The integrating circuit is interposed between the bias circuit and a reference voltage. The integrating circuit comprises an integrating capacitor connected in series to the bias circuit and connected between the bias circuit and the reference voltage. The integrating capacitor is configured to maintain a substantially null charge during a phase of measurement of a ionization current as to measure a substantially null value of an integral of the ionization current, in the case of a misfire of the comburent-combustible mixture.

An electronic device for controlling an ignition coil of an internal combustion engine includes a high voltage switch, a driving unit and a control unit. The driving unit controls the closure of the switch during charging energy in the primary winding and the opening of the switch during transferring energy from the primary winding to a secondary winding. A current measuring circuit is connected in series to a second terminal of the secondary winding to detect current generated on the secondary winding during the charging step and generate a signal representative of the detected current. The control unit receives the signal representative of the current detected by the measuring circuit, compares a relevant value of such signal with a predefined first reference value and activates a mode for detecting a soiling of the spark plug when the relevant value of the signal exceeds said predefined first reference value.

A switch control circuit controls a switch element connected to a primary coil of an ignition coil in accordance with an ignition signal. The switch element includes a transistor and a protection element connected between a collector and gate of the transistor. The switch control circuit uses a voltage at a gate terminal controlling the transistor or a voltage corresponding to a collector current of the transistor as a detection voltage and generates a status detection signal corresponding to a change in the detection voltage.