A semiconductor device includes a power semiconductor element that is connected between a first terminal on a high potential side and a second terminal on a low potential side and that is controlled to be on or off corresponding to a gate potential, a turn-off condition detector that detects whether a control signal input from a control terminal and controlling the power semiconductor element satisfies a predetermined turn-off condition, a first switching element that controls the gate potential of the power semiconductor element to be an off-potential when the turn-off condition detector detects that the turn-off condition is satisfied, and a detector for a collector current of the power semiconductor element. The turn-off condition detector uses the control signal and the collector current as the turn-off condition.

In a general aspect, a circuit for controlling operation of an ignition circuit including an insulated-gate bipolar transistor (IGBT) device can include a current slope detection circuit configured to detect a slope of a current in a primary winding of an ignition coil included in the ignition circuit and a driver circuit coupled with the current slope detection circuit. The current slope detection circuit can be further configured to, during charging of the ignition coil, if the detected slope is above a first limit, provide a first indication to the driver circuit; and, if the detected slope is below a second limit, provide a second indication to the driver circuit. The driver circuit can be configured to, in response to receiving the first indication or the second indication, modify operation of the ignition circuit.

The invention relates to a method and a device for igniting a gas-fuel mixture, in particular in internal combustion engines, wherein at least one gas discharge gap bounded by two electrodes is ignited by means of a high voltage, which is produced by an ignition circuit and applied to the gas discharge gap. After the breakdown of the gas discharge gap, the current through the gas discharge gap is controlled by a control circuit in such a way that the gas discharge lies in the abnormal glow range, in which the voltage across the gas discharge gap rises for currents greater than 0.1 A having a positive slope. The current through the gas discharge gap is controlled in such a way that said current lies between 0.1 A and 10 A, preferably is greater than 0.1 A and less than or equal to 3 A, more preferably lies between 0.5 A and 1 A, wherein the voltage lies between 250 V and 3000 V, preferably between 500 V and 2000 V. The duration of the current flow through the gas discharge gap or the period of the current flow through the gas discharge gap is controlled in such a way that said duration or period lies between 0.01 s and 50 s, preferably between 0.1 s and 10 s.

An ignition device at least equipped with a DC power source, an ignition coil unit, a spark plug, an ignition switch, and an auxiliary power source, wherein the auxiliary power source is at least equipped with a discharge energy accumulating means, a discharge switch, and a discharge driver. The ignition device is further equipped with a secondary-current feedback controlling means comprising a secondary current detecting means for detecting a secondary current flowing during the ignition coil unit discharge period, and a secondary current feedback control circuit-for determining an upper limit and a lower limit for the secondary current from binary threshold values, and driving so as to open and close the discharge switch on the basis of the determination results. Furthermore, energy is introduced from the auxiliary power source without switching the polarity of the secondary current.

Described is an ignition coil comprising a housing, in which a transformer is arranged, and a plug connector, wherein the plug connector has a high voltage contact, which is connected to the secondary side of the transformer by means of a wire, which resiliently presses against an electrical contact surface. The contact surface is concavely shaped.

An ECU outputs an ignition signal Si to an ignition apparatus through an ignition communication line. The ignition apparatus performs the closing operation of an ignition switching element, in a period during which the ignition signal Si is input. The ECU outputs a discharge waveform control signal Sc to a waveform control communication line, at a timing that is delayed by a predetermined delay time relative to an output timing of the ignition signal Si. In an input period of the discharge waveform control signal Sc after the stop of the input of the ignition signal Si, the ignition apparatus controls the electric current to flow through a primary coil, to a discharge current command value that is decided depending on the above delay time, by the opening-closing operation of a control switching element.

A one-chip igniter is formed by a convenient manufacturing process and at a low cost. A device to switch a power semiconductor switch is provided, the device comprising a first semiconductor switch which is turned on or turned off in response to a first control signal input to a gate and, if turned on, provides a high voltage to a gate of the power semiconductor switch, and a voltage boosting circuit which boosts a voltage of the first control signal that turns the first semiconductor switch on. As one example, the voltage boosting circuit boosts a voltage of the first control signal which turns the first semiconductor switch on to a higher voltage than a high voltage.

An ignition apparatus performs energy input control in which energy is continuously inputted to an ignition coil to enable a spark discharge in a predetermined energy input period after interrupting a primary current by an ignition switch and generating a discharge of a spark plug by a secondary current. A combustion state determination circuit determines a combustion state by comparing a combustion pressure P detected by a combustion state detector. When the combustion pressure P is smaller than a second threshold Pth2, and there is room for improving the combustion state with respect to the present energy input condition, the energy input period IGW is increased or a target secondary current I2* is increased. By compensating the condition of the energy input control in accordance with the combustion state, a target combustion state can be achieved with just enough energy consumption.

A one-chip igniter is formed by a convenient manufacturing process and at a low cost. A device to switch a power semiconductor switch is provided, the device comprising a first semiconductor switch which is turned on or turned off in response to a first control signal input to a gate and, if turned on, provides a high voltage to a gate of the power semiconductor switch, and a voltage boosting circuit which boosts a voltage of the first control signal that turns the first semiconductor switch on.

As one example, the voltage boosting circuit boosts a voltage of the first control signal which turns the first semiconductor switch on to a higher voltage than a high voltage.

The present invention discloses a device having communication with small gasoline engine igniter, comprising an igniter, a flameout switch and a communication device, and both the flameout switch and the communication device are connected to an igniter flameout port and an iron core of a reference ground. The unique voltage conversion circuit herein makes the signals at MUC sampling port more close to the required theoretical value, to ensure more stable and reliable communications. The design of key input and data display enables the communication device to be used alone without additional computers or other additional equipments, simple and convenient. On the basis of above igniter program, very simple circuit at extremely low costs is added, together with the MCU control program, the invention can have a single-wire bidirectional communication with an external device, so as to achieve operations of controlling MCU internal data of the igniter.