A semiconductor device for internal combustion engine ignition includes: a power semiconductor switching device that switches ON and OFF in accordance with a control signal provided by an external control circuit for causing a spark plug to produce sparks via an ignition coil and an external power source; an auxiliary voltage circuit that generates and applies an auxiliary voltage responsive to a collector voltage of the power semiconductor switching device to the gate of the power semiconductor switching device; and a constant current circuit that regulates current from the auxiliary voltage circuit to the gate of the power semiconductor switching device when a high-voltage surge originating from the external power source is applied to the auxiliary voltage circuit via a primary winding of the ignition coil.

A semiconductor device includes a power semiconductor switching element including a characteristic test terminal, and a control circuit configured to control an operation of the power semiconductor switching element. The power semiconductor switching element and the control circuit are formed in a same chip. The control circuit includes a gate voltage generation circuit configured to generate a current limit gate voltage for restricting an overcurrent flowing in the power semiconductor switching element in a desired range when an abnormality occurs, based on a characteristic of the power semiconductor switching element which is measured in advance by applying a voltage to the characteristic test terminal.

Circuits and methods for controlling a coil current are disclosed. The control utilizes current sources to source/sink charge to/from a capacitance of a switching device to turn the switching device ON/OFF. When turned OFF, the switching device blocks coil current from flowing, which can create a large kickback voltage on the coil. To reduce the large kickback voltage, the capacitance can be discharged slowly by a small discharge current. The disclosed circuits and methods provide a gradual reduction of the coil current at a rate that is slow enough to prevent a spark while minimizing a period for shutdown to prevent overheating. The disclosed systems and methods may be simpler than other approaches because the soft shutdown is no ramp signal is required for the reduction. Instead, a rate of gate capacitance discharge is controlled to maintain the kickback voltage at a particular level.

An ignition system including a spark plug control unit adapted to control at least two coil stages to provide a current to a spark plug, including two stages including a first transformer including a first primary winding inductively coupled to a first secondary winding; a second transformer including a second primary winding inductively coupled to a second secondary winding; the control unit enabled to simultaneously switch on and off two corresponding switches to maintain a continuous ignition fire, and includes a step-down converter stage with a switch and a diode. The method includes i) switching off the switch; and ii) toggling the two corresponding switches.

A powertrain control system may include an engine and a controller. The controller may be configured to, responsive to a maximum difference in battery voltage values remaining less than a threshold value during a period in which a number of engine stop-start cycles exceeds a limit, enable an automatic stop-start system of the engine.

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.

An ignition system includes a controller which controls two stagesto provide current to a spark plug. The stages include a first transformer including a first primary winding and a first secondary winding and a second transformer including a second primary winding and a second secondary winding. A switch is electrically connected between a supply high side and the high side of the first primary winding. A second switch is electrically connected between the first primary winding and the power supply low side supply. A third switch is connected between the junction of the switch and high side end of the first inductor and a point between the low side of the second primary winding and low side supply. A fourth switch is located between the low side of the second primary winding and the point. A fifth switch is located between the point and low side supply.

In an ignition control apparatus, a control unit controls switching elements so as to supply a primary current to the other end side of a primary winding opposite to one end thereof connected to a DC power source by discharging (which is performed by turning on a second switching element stored energy from a capacitor during ignition discharge (which is started by turning off a first switching element. In particular, the control unit controls the second switching element or the third switching element so as to provide variability to the amount of stored energy discharged from the capacitor according to an operating state of an internal combustion engine.

An internal combustion engine igniter of the present invention includes a current limiting circuit that limits current flowing to the IGBT by controlling a gate voltage of the IGBT in accordance with the current flowing to the IGBT, a waveform-shaping circuit that suppresses an oscillation of the current flowing to the IGBT by applying to the gate voltage of the IGBT an auxiliary voltage generated from a collector voltage of the IGBT when current is being limited by the current limiting circuit, and, in addition, a heat-generation suppressing circuit that obtains an intermediate voltage by resistively dividing the auxiliary voltage generated by the waveform-shaping circuit when current is being limited by the current limiting circuit, and that suppresses IGBT heat generation by increasing the current flowing to the IGBT in accordance with the intermediate voltage.

A drive circuit that operates stably and has a small circuit size. Provided is a switch apparatus including a power semiconductor element connected between a first terminal on a high potential side and a second terminal on a low potential side; a capacitor; a charging section that charges the capacitor for at least a portion of an interval during which the power semiconductor element is OFF; a discharging section that causes the capacitor to gradually discharge, in response to the power semiconductor element becoming ON; and a cutoff section that sets the power semiconductor element to an OFF state, in response to a voltage of the capacitor becoming lower than a threshold voltage.