Abstract: A semiconductor device 1 has an IGBT region and a MOSFET region. A plurality of channel doped P layers formed in the MOSFET region include a trench-adjacent channel doped P layer whose side surface is in contact with a boundary trench gate formed between the IGBT region and the MOSFET region. A formation depth of the trench-adjacent channel doped P layer is set deeper than a formation depth of the boundary trench gate. In the MOSFET region, an N type MOSFET having a planar structure is configured including a channel region in the channel doped P layer, a gate insulating film in an interlayer oxide film, and a gate polysilicon serving as a planar gate.

Abstract: A semiconductor device includes an IGBT, a constant voltage circuit, and protection Zener diodes. The IGBT makes/breaks a low-voltage current flowing in a primary coil. The constant voltage circuit and the protection Zener diodes are provided between an external gate terminal and an external collector terminal. The constant voltage circuit supplies a constant gate voltage to the IGBT to thereby set a saturation current value of the IGBT to a predetermined limiting current value. The IGBT has the saturation current value in a limiting current value range of the semiconductor device.

Abstract: A system, circuit, and method are provided for generating continuous plasma to control combustion including the ignition and maintenance of the combustion process. An electric potential difference is generated across a pair of electrodes in a combustible bulk gas in the form of an oscillating driving potential just below the arcing threshold which alternates in polarity to cause an alternating gap current between the electrodes which generates continuous plasma to contribute to combustion of the bulk gas by providing for more efficient combustion.

Abstract: A power circuit, which supplies plasma energy to a spark plug, includes a DC/DC converter which charges a tank capacitor, a voltage limiting circuit which restricts an output voltage of the converter to a predetermined value, a PJ capacitor which is connected to the output side of the converter and is charged by the tank capacitor, and a high breakdown voltage switch which is connected between the PJ capacitor and the DC/DC converter and controls a charging time period of the PJ capacitor in response to operating conditions of an internal combustion engine; and the power circuit switches a voltage limiting value of the tank capacitor for charging the PJ capacitor in synchronization with a driving signal of the high breakdown voltage switch.

Abstract: A buffer circuit is provided between a gate terminal of a pull-down transistor and a threshold circuit receiving a gate signal as an input signal. A voltage applied to an output terminal of a power semiconductor element from an external battery power supply is supplied to the buffer circuit through a resistive element. The buffer circuit converts the level of an on-signal output from the threshold circuit into a voltage higher than the threshold of the pull-down transistor, so that the pull-down transistor operates surely to turn off the power semiconductor element even when the level of the gate signal is low. Thus, there is provided a semiconductor integrated circuit device having a power semiconductor element which can be turned off by sure operation of a pull-down semiconductor element.

Abstract: A controller for an ignition coil, the controller comprising means for determining a rate of change of current flow through a primary winding of the ignition coil; and means for switching off current flow through the primary winding of the ignition coil as a function of the rate of change of current.

Abstract: A semiconductor device includes an IGBT, a constant voltage circuit, and protection Zener diodes. The IGBT makes/breaks a low-voltage current flowing in a primary coil. The constant voltage circuit and the protection Zener diodes are provided between an external gate terminal and an external collector terminal. The constant voltage circuit supplies a constant gate voltage to the IGBT to thereby set a saturation current value of the IGBT to a predetermined limiting current value. The IGBT has the saturation current value in a limiting current value range of the semiconductor device.

Abstract: A capacitive discharge ignition system for an internal combustion engine and for use with a generator powered current source comprises a storage capacitor, at least one power thyristor for discharging the storage capacitor to transfer energy to at least one coil triggered in synchronism with an internal combustion engine with which the ignition system may be associated. A triggering circuit biases the power thyristor to discharge the storage capacitor. A shut-off circuit comprises a solid state device for switching the output of the generator to ground interrupting the flow of current to the power thyristor. A circuit sensing current flow in the triggering circuit generates a control and gates the solid state device into conduction in response to the control signal.

Abstract: An ignition coil apparatus for an internal combustion engine with a cylinder having first and second spark plugs can reliably detect an ionic current without discharging a bias voltage even at the start of supplying a primary current. The apparatus includes a coil member with primary and secondary coils. The secondary coil has first and second ends connected to the spark plugs through high voltage output terminals, respectively. A first diode has its anode connected to a capacitor, and its cathode connected between the first end of the secondary coil, at which a high positive voltage is generated upon interruption of the primary current, and a high voltage output terminal at a secondary coil first end side. A second diode has its anode connected to the secondary coil first end, and its cathode connected to a junction between the first diode and the high voltage output terminal.

Abstract: In an engine ignition system, an igniter for an ignition coil is connected to an ECU through a signal wire. The signal wire is grounded via the collector and the emitter of a bipolar transistor of an output circuit of the igniter. A constant current source outputs a current to the base of the bipolar transistor. Switching transistors are connected between the emitter and base of the bipolar transistor. When all the switching transistors are turned off, the bipolar transistor is turned on.

Abstract: An apparatus for producing an ignition spark in an internal combustion engine. The apparatus comprises an inductive ignition device having a primary coil and a secondary coil, flow of current through the primary coil being controlled by an electronic switching element (e.g., a transistor) responsive to a triggering signal. A rotatable body (e.g., the engine flywheel) having detectable features on a periphery thereof is also provided. A sensor device is located adjacent to the rotatable body at a fixed position and is operative to produce an output in response to the detectable features. The apparatus also includes a controller operative to receive an output from the sensor device and responsively produce the triggering signal so as to have a selected dwell time and ignition position.

Abstract: A power switching control device for electric systems such as an ignition device for internal combustion engines has a control circuit IC and a switching IC. A temperature sensor is provided in the switching IC. The control circuit IC is joined to a grounding terminal through a conductive layer provided therebetween. Thus, the substrate potential of the control circuit IC is stabilized to the ground potential so that the temperature sensor is prohibited to operate erroneously due to electromagnetic noise.

Abstract: A spark plug circuit for, and a method of, reducing or preventing the corrosion of a spark plug electrodes in an internal combustion engine. The circuit and method provide a positive voltage across the center electrode/ground electrode gap, which repels positively charged corrosion mechanisms, such as calcium and phosphorus ions.

Abstract: An ignition system for an internal combustion engine includes an ignition coil, electric power supply circuit, a switching transistor, engine condition detecting element or unit that detects a signal relating to flow speed of air-fuel-mixture gas in the engine, and ignition control unit that controls the switching transistor to provide multiple ignition sparks in a predetermined ignition period. The ignition control unit controls the switching transistor to maintain each of the ignition sparks according to the signal relating to the flow speed of air-fuel-mixture gas in the engine to maintain sufficient spark energy for igniting the air-fuel mixture gas.

Abstract: A circuit for controlling an ignition coil is provided. The circuit includes a first transistor, second transistor, and a capacitor. The first transistor is connected in electrical series between the ignition coil and a voltage reference. The capacitor is connected between the ignition coil and a control input of the first transistor. The second transistor is configured to selectively connect the capacitor to the voltage reference.

Abstract: Two embodiments of an integrated ionization detection circuit and ignition coil driver, an ASIC and a single electronic package, are disclosed. The apparatuses reduce the cost and complexity of an in-cylinder ionization detection system by combining like functionality into one ASIC or electronic module easing packaging constraints. In both embodiments, a current sink is used. The current sink removes noise in the form of voltage splices. The voltage spikes are high voltage, but of short duration. The current sink prevents these spikes from turning on the IGBT. However, the current sink allows the IGBT command signal to pass. This device also comprises a switch whereby ionization current and coil primary current are multiplexed.

Abstract: An igniter of the present invention has an insulated gate semiconductor device having a collector terminal, an emitter terminal and a gate terminal, a current control circuit which limits current by controlling voltage at the gate terminal when current for flowing through the insulated gate semiconductor device exceeds a fixed value, a voltage monitor circuit for detecting a potential of the collector, and a control current adjusting circuit for controlling current which flows through the gate terminal by receiving output from the voltage monitor circuit.

Abstract: An internal combustion engine ignition apparatus includes a switching circuit having no power supply terminal connected to a power supply such as a battery is constructed, and including an output terminal connected to an ignition coil, an input terminal for receiving an ignition signal voltage and a reference potential terminal connected to a reference potential. In the switching circuit, the terminal structure is simplified, and energization timing and ignition timing can be set more accurately. A current supply circuit is connected between the input terminal and the reference potential terminal, and a current is supplied from the current supply circuit to a drive resistor of the switching element. In this current supply circuit, an energization timing when supply of the driving current is started is controlled by a waveform shaping circuit operating by the ignition signal voltage, and an ignition timing when the driving current is interrupted is controlled.

Abstract: There is proposed an internal combustion engine ignition apparatus in which a switching circuit having no power supply terminal connected to a power supply such as a battery, and includes an output terminal connected to an ignition coil, an input terminal for receiving supply of an ignition signal voltage, and a reference potential terminal connected to a reference potential. A current supply circuit is connected between the input terminal and the reference potential terminal, and a current is supplied from the current supply circuit to a drive resistor of the switching element. This current supply circuit is controlled by a constant current circuit, and supplies a driving current, which is made a constant current, to the drive resistor between a rising portion of the ignition signal voltage and a falling portion thereof. The driving current, which is made the constant current, keeps the gate voltage of the switching element being constant in the on period.

Abstract: An ignition system and a method for operating an ignition system provides reliable suppression of a closing spark ignition at relatively small expense and to achieve a reliable ignition by the ignition spark. To assure a high energy supply to the spark plug, an ignition system is created having a functional device for receiving a drive signal and for producing a pulse signal, an ignition transistor for receiving the pulse signal, an ignition coil, whose primary winding connections are connected in a primary current circuit that is fed by a vehicle power supply source and that can be switched using the ignition transistor, and whose secondary winding connections are connected in a secondary current circuit for receiving a spark plug.

Abstract: An ignition coil assembly for providing ignition energy to a spark plug in accordance with a dwell pulse and transmitting diagnostic data related to an ignition event occurring after the dwell pulse. The assembly has an ignition coil with a spark plug terminal adapted to mate with the spark plug, and a transistor for conducting current flow through the primary winding of the ignition coil. The current flow is in accordance with the dwell pulse, which arrives over a signal line. A diagnostic block receives at least one electrical signal from the ignition coil and derives diagnostic data therefrom for transmitting over the same signal line in the absence of the dwell pulse.

Abstract: A method for operating an internal combustion engine and a corresponding device are described, in which reference pulses are generated synchronously with respect to the cyclical movement of at least one part of the internal combustion engine. At least one event moment for the occurrence of at least one event is calculated by an output unit at specific, definitively preset time intervals of the cyclical movement. Moreover, an independent clock-pulse generator is provided which generates clock pulses, the interval of the clock pulses being independent of the movement, and the interval of the clock pulses being smaller than the interval of the reference pulses. The at least one event moment is expressed as the number of clock pulses of the independent clock-pulse generator, and the at least one event is triggered upon reaching the number of clock pulses.

Abstract: This feature of the present invention comprises two embodiments of an integrated ionization detection circuit and ignition coil driver according to the present invention, an ASIC and a single electronic package. The apparatuses reduce the cost and complexity of an in-cylinder ionization detection system by combining like functionality into one ASIC or electronic module easing packaging constraints. In both embodiments, a current sink is used. The current sink removes noise in the form of voltage spikes. The voltage spikes are high voltage, but of short duration. The current sink prevents these spikes from turning on the IGBT. However, the current sink allows the IGBT command signal to pass. This feature of the present invention also comprises a switch whereby ionization current and coil primary current are multiplexed.

Abstract: This feature of the present invention comprises a method and apparatus that provides a regulated power supply for in-cylinder ionization detection by harvesting the excess ignition coil leakage and magnetizing energy immediately following the turn off of the ignition coil IGBT. It uses an additional energy storage capacitor which replaces a first capacitor as the primary energy storage device. Thus, this feature of the present invention uses a two step method for charging the ionization detection circuit, as opposed to just one stage. The second capacitor is charged first, typically up to 400 Volts DC, and is then used as a reservoir to charge the first capacitor.

Abstract: In a first preferred embodiment, the present feature of the invention multiplexes both the ionization and driver current feedback signals into one signal, thus reducing cost and making coil packaging easier. The multiplexed signal first outputs the ionization detection signal and then replaces the ionization signal with the charge current feedback signal when the charge command Vin is enabled. In other words, the multiplexed feedback signal outputs the ionization feedback signal and switches to the charge current feedback signal when the charge command Vin is active. In a second preferred embodiment, the present feature of the invention comprises a method and apparatus to multiplex the ignition driver gate signal with both the ignition coil charge current feedback signal and the ionization signal, thus reducing the package pin count by two.

Abstract: An electronic component, such as an IGBT, that presents a control terminal for receiving a stepwise control signal and at least one other terminal adapted for reaching a given voltage level by effect of the application of the step signal, with the possibility of overshoot occurring; and a damping resistive element interposed between the control terminal and the at least one other terminal. The damping resistive element shows a current saturated behavior correlated to voltage increase applied at the terminals towards the given voltage level, thus eliminating the risk of occurrence of overshoot in the voltage of the IGBT collector, and preventing the undesired re-ignition of the IGBT when it is in a cut-off condition, by inducing an overvoltage on the collector terminal.

Abstract: A control circuit 130 carries out ON/OFF control of a primary current flowing in an ignition coil in response to an input ignition control signal. The control circuit 130 and an insulated-gate bipolar power transistor (IGBT) 110 are integrated on a monolithic silicon substrate. The control circuit 130 includes a plurality of control circuit blocks of different functions formed on the silicon substrate. The circuit functions of the control circuit blocks are enabled and disabled by changing wiring patterns.

Abstract: A product, product by process, and process according to the present invention integrates an ignition coil driver electronics or ignitor into a plughole coil housing. Electronic components are mounted directly to a printed circuit board serving as a direct connection to connector terminals and/or coil leads via plated-apertures. If required, at least one protective layer can be applied directly to an external surface of at least some of the electronic components mounted on the printed circuit board to compensate for differences in the coefficients of thermal expansion. The protective layer is selected from a group including a conformal coating, a soft buffer material, a hard epoxy globtop, and combinations thereof.

Abstract: A circuit for supplying an oscillation suppress current is provided between a collector terminal and gate electrode of a main IGBT. The current supply circuit comprises a resistor and a diode which are connected in series. A bypass MOSFET is connected between the series connection and the emitter terminal. No semiconductor element having different temperature characteristics is provided in the current supply circuit.

Abstract: In an engine igniter 1, when a spark-discharge duration time Tc calculated on the basis of operation conditions of an internal combustion engine has elapsed after generation of spark discharge by an ignition coil 13, an electricity-supply resumption circuit 51 is operated in order to resume supply of primary current i1 to a primary winding L1, to thereby interrupt the spark discharge. Further, a signal processing control circuit 23 performs electricity-supply-start timing delay control processing in order to delay the timing of supplying electricity to the primary winding L1 in accordance with the power source voltage, to thereby maintain the magnetic flux energy accumulated in the ignition coil 13 at a substantially constant level.

Abstract: The present invention comprises an Electronics Control Unit (ECU) power potential stabilizing circuit and an ECU reference potential stabilizing circuit. The ECU power potential stabilizing circuit eliminates noise and stabilizes voltage variation occurring when the electrical parts of automobile are activated by the power supplied through the ECU of the electronic accelerator, by impressing it to the power supply line and variable voltage supply line. The ECU reference potential stabilizing circuit eliminates the unnecessary spark noise and harmonics noise occurring on the power supply line, reference potential line and variable voltage supply line, by impressing it to the variable voltage supply line and reference potential line. It further stabilizes the voltage supplied to the ECU by compensating the voltage fluctuated due to disturbances.

Abstract: A circuit for supplying an oscillation suppress current is provided between a collector terminal and gate electrode of a main IGBT. The current supply circuit comprises a resistor and a diode which are connected in series. A bypass MOSFET is connected between the series connection and the emitter terminal. No semiconductor element having different temperature characteristics is provided in the current supply circuit.

Abstract: A circuit for supplying an oscillation suppress current is provided between a collector terminal and gate electrode of a main IGBT. The current supply circuit comprises a resistor and a diode which are connected in series. A bypass MOSFET is connected between the series connection and the emitter terminal. No semiconductor element having different temperature characteristics is provided in the current supply circuit.

Abstract: For minimizing spark energy and improving durability of a spark plug (13) without controlling a time for energizing a primary wiring (L1); the ignition unit (1,2 and 3) for an internal combustion engine is arranged in that actions of a transistor (17) are controlled by an ECU (19) to abruptly interrupt a primary current (i1) such that high voltage for ignition induced to a secondary wiring (L2) is applied on the spark plug (13) for generating spark discharge. For forcibly interrupting spark discharge at a spark discharge duration, the ECU (19) switches the thyristor (21 and 210) ON to supply current to the primary wiring (L1) for forcibly interrupting the spark discharge. By controlling the spark discharge duration to be optimum on a basis of an operating condition of the internal combustion engine, it is possible to restrict generation of multiple discharge and to restrict exhaustion of electrodes of the spark plug (13).

Abstract: An electronic component, such as an IGBT, that presents a control terminal for receiving a stepwise control signal and at least one other terminal adapted for reaching a given voltage level by effect of the application of the step signal, with the possibility of overshoot occurring; and a damping resistive element interposed between the control terminal and the at least one other terminal. The damping resistive element shows a current saturated behavior correlated to voltage increase applied at the terminals towards the given voltage level, thus eliminating the risk of occurrence of overshoot in the voltage of the IGBT collector, and preventing the undesired re-ignition of the IGBT when it is in a cut-off condition, by inducing an overvoltage on the collector terminal. FIG. 5 is the one selected.

Abstract: The primary winding of an ignition coil is connected in series with an ignition switch that can be switched by a control circuit. A circuit including a capacitor, a resistor, and a diode is configured between the control terminal and the collector of the ignition switch. When the primary current is switched on, the capacitor discharge brings about a voltage reduction at the base of the ignition switch resulting in slowing down the trailing voltage edge at the collector of the ignition switch.

Abstract: The present invention is an electrical system for an engine of the type used to power a watercraft. A primary power supply of the system is connected to a main circuit by a feed circuit. A main switch controls the flow of power from the primary power supply to the main circuit through the feed circuit. An auxiliary power supply is connected to the main circuit in a manner which allows power to flow from the auxiliary power supply to the main circuit even if the main switch is preventing power to flow from the primary power supply to the main circuit.

Abstract: An ignition system for an internal combustion engine is provided which includes an ignition coil formed with a primary winding and a secondary winding and a switching element for interrupting a current flow through the primary winding of the ignition coil at given timing. The ignition coil has a secondary winding to primary winding turns ratio a which meets the condition of V.sub.D .multidot.a >V.sub.r where V.sub.r is a required voltage of a spark plug of the engine and V.sub.D is a breakdown voltage of the switching element which is greater than or equal to 450 V.

Abstract: The power transistor unit 2A for controlling the current supply to the primary side of the ignition coil 3 includes a light emitting diode 10 coupled to the output of the control unit 1, and a phototransistor 11 optically coupled to the light emitting diode 10. The light emitting diode 10 and the phototransistor 11 together constitute a optoisolator. Thus, the ignition coil 3 is electrically isolated from the control unit 1, and hence a filter circuit for suppressing noise from the ignition coil 3 can be dispensed with.

Abstract: The system comprises: at least one spark plug, at least one ignition coil whose secondary winding is connected to the plug, a power transistor whose output path is in series with the primary winding of the coil between the two terminals of a direct-current voltage supply, and a control circuit for switching the transistor from the cut-off condition to the saturated condition to enable current to flow in the primary winding of the coil in order to generate a spark. Conveniently, the control circuit is arranged to switch the transistor progressively from the cut-off condition to the saturated condition, in dependence on the voltage detected between the terminals of its output path by the application of a driver signal which is first continuous and then pulsed.

Abstract: A contactless ignition apparatus for an internal combustion engine comprises a resin-molded closed magnetic circuit type ignition coil including an iron core constituting a closed magnetic circuit, a primary winding and a secondary winding wound around the iron core, respectively, and mold resin for insulating the primary and secondary winding, a semiconductor switching circuit for interrupting a current flowing to the primary winding, and an ignition plug to which a high voltage generated in the secondary winding upon interruption of the primary current flow to the primary winding by the semiconductor switch circuit. The falling rate dI/dt of the primary current upon interruption thereof by the semiconductor switching circuit is set at a value in a range of 0.2 to 0.4 A/.mu.s. Noise radiation from the ignition coil can be reduced significantly.

Abstract: A high-voltage switch is suggested which is usable particularly as an ignition voltage distributor for applying the ignition voltage to spark plugs of an internal combustion engine. The high-voltage switch comprises a cascade circuit of optoelectric semiconductor elements which are actuated or connected through by means of incident light radiation. Very high voltages can accordingly be switched in an exact manner, wherein a galvanic separation is provided between control circuit and high-voltage circuit. The control circuit can be operated with low voltage, so that use in connection with electronic ignition systems is particularly simple.

Abstract: Disclosed is an ignition apparatus for an internal combustion engine adapted to be started by the rotation of a crank shaft upon rotation of a starter. A sensor detects first and second different angular positions of the crank shaft to change the output level at the respective angular positions. In response to the output of the sensor, the ignition coil is energized and then de-energized. When a voltage generated by the starter is detected upon the reverse rotation of the rotary member, the state of the ignition coil is maintained unchanged.

Abstract: A discharge load driving circuit has a transformer with a low voltage coil and a high voltage coil wound around a magnetic core. The high voltage coil has a transformation ratio for setting a high self-resonance frequency value for the transformer to thereby output high voltage at a short rise time period. The discharge load driving circuit further includes a switching element connected to the transformer for switching on and off a d-c input supplied thereto through the low voltage coil of the transformer. The discharge load driving circuit further includes a driver circuit for driving a switching element driving pulse, a control circuit for controlling the driver circuit, a discharge load connected to the high voltage coil for discharging load by a high voltage output generated in the high voltage coil when the switching element is turned on, and a detector for detecting a flow of discharge current in the discharge load. The switching element repeats its on-off action in a predetermined.

Abstract: An ignition device for an internal combustion engine comprises a sensor for producing a first and a second angular angle corresponding to a first and a second crank position, respectively, a flip-flop circuit which is set or reset by the first angular signal of the sensor and is reset or set by the second angular signal, ignition control unit for controlling the primary current of an ignition coil based on the output of the flip-flop circuit and carrying out the ignition operation based on the second angular signal, unit for producing a voltage when the internal combustion engine reverses, and unit for comparing the voltage produced by the voltage producing unit with a predetermined voltage, and causing the second angular signal to be ignored depending on the results of comparison so as to prevent the flip-flop circuit from being reset or set.

Abstract: An electromagnetic coil operates a fuel injector valve and generates a high voltage pulse to ignite a spark plug in an internal combustion engine. The primary and secondary windings of a coil are disposed between inner and outer cores. Electric current flowing at a first level through the primary winding induces magnetic flux in a first flux path to move a fuel flow control member to open a fuel flow path between a fuel inlet and a fuel outlet in the fuel injector valve. Current flowing at a second higher level through the primary winding induces a higher level of magnetic flux in a second flux path to move the fuel flow control member to a position closing the fuel flow path. A controller generates the first and second primary winding currents at the proper time in the engine operating cycle in response to engine operating conditions.

Abstract: An ignition system for internal combustion engines is constructed so that, in response to each ignition signal from ignition signal generating means, through a predetermined angle before a succeeding ignition timing, a storage quantity of storing means is gradually increased from an initial value and then it is gradually decreased, and a time point when the storage quantity of the storing means has been decreased to reach the initial value is detected by first storage quantity detecting means to thereby turn on a power transistor for turning on and off a primary current of an ignition coil at that time point, and further the fact that the storage quantity of the storing means has been decreased to reach a set value larger than the initial value is detected by second storage quantity detecting means to thereby change a decrease rate of the storage quantity of the storing means.

Abstract: To control the ON or conduction time of a transistor (4) serially connected with the primary winding (2) of an ignition coil, the voltage drop across the collector or base respectively, and emitter is sensed and used as a control parameter with respect to a set or reference value determining current flow through the ignition coil under conditions of complete discharge of stored energy from the ignition coil. Conditions of complete discharge occur within a first speed range; in other speed ranges, in which residual stored energy remains within the ignition coil, indicative of current flow therethrough starting from a value other than zero or null, the voltage sensed across the transistor is compared with the reference value, and the current flow time adjusted in dependence on the comparison.

Abstract: The invention teaches an ignition device for internal combustion engines, comprising at least one spark gap with two ignition electrodes for generating ignition sparks between them, whereby neither of the two ignition electrodes is connected to the ground potential of the internal combustion engines; an ignition current source which is coupled to the ignition electrodes, insulated from ground, to generate the sparks, and forming an ignition circuit therewith; a voltage source, which has one pole at ground, while its other pole is connected to the ignition circuit, so that the ignition circuit is at the same potential as the voltage source and a separate plasma circuit is formed which comprises the voltage source, at least one of the two electrodes, a plasma composed of hot combustion gases between the ignition electrodes and ground, in a series circuit; and means in the plasma circuit which deliver an output pulse corresponding to the strength and time pattern of the current in the plasma circuit.

Abstract: In an ignition system for an internal combustion engine, a signal generator generates a given ac signal in synchronism with the rotation of the engine and a waveform reshaping circuit reshapes the waveform of the ac signal from the signal generator thus generating a pulse signal. An ignition timing control circuit is responsive to the pulse signal from the waveform reshaping circuit to control the timing of ignition of an ignition coil in which a primary current is switched on and off in accordance with the pulse signal.