An igniter includes a switch element with input, output control electrodes, a first lead in contact with the input electrode and connected to a primary coil of an ignition coil, a second lead that is grounded, a third lead spaced apart from the first and second leads, a first bonding wire connecting the output electrode and the third lead, a second bonding wire connecting the third lead and the second lead, and a control IC that drives the switch element based on an ignition instruction signal from an engine control unit. The control IC generates an ignition confirmation signal based on the voltage of the third lead, and outputs the signal to the engine control unit.

Various embodiments of the present technology comprise a method and apparatus for an ignition system. In various embodiments, the ignition system activates a soft shutdown of an ignition coil in the event of an over dwell condition. The apparatus comprises a first counter and a second counter that are selectively activated at predetermined events. An output of the second counter controls the value of a reference current that decreases linearly over time and wherein a rate of change of the reference current may be adjusted according to a frequency of a clock signal. In various embodiments, the soft shutdown operates independent of the supply voltage and temperature.

It is made possible to control ignition appropriately. An ignition device 1 for an internal combustion engine includes a spark coil 50 including: a primary side coil 51 connected to a direct current power supply 40 and a secondary side coil 52 magnetically connected to the primary side coil 51 and connected to an ignition plug 60; a switch element 30 that performs switching between energization and interruption of primary current I1 to the primary side coil 51; and a switch element controlling circuit 20 that controls the switch element 30 on the basis of an ignition controlling signal 51 supplied from an ECU 10. A turn-on delay adjustment circuit 22 that delays a control timing of the switch element 30 is disposed between the ECU 10 and the switch element 30 such that first resonance noise generated due to interruption of the primary current I1 to the primary side coil 51 is reduced.

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.

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 circuit configured to control a switching device to reduce a current in a charged coil is disclosed. The circuit is configured to monitor a kickback voltage generated by the decreasing current in the coil. The circuit is further configured to adjust a rate at which the current is reduced in order to limit the kickback voltage. Limiting the kickback voltage during shutdown can prevent a spark at a spark gap that is inductively coupled to the coil and can allow for greater flexibility in the time taken to shut down the coil without overheating components or generating an unwanted spark. Additional, limiting the kickback voltage during shutdown can allow for a pseudo ramp wave to control the circuit during the shutdown because voltage spikes cause by abrupt changes in the pseudo ramp wave are limited.

In an implementation, a method of operating an ignition circuit can include enabling a charge path control circuit and a switch circuit to charge a primary winding of an ignition coil of the ignition circuit until a threshold current is reached in the primary winding. After reaching the threshold current in the primary winding, the method can include maintaining a current in the primary winding of the ignition coil in correspondence with a current limit by alternatively activating and deactivating the charge path control circuit complementary to alternative activation and deactivation of a circulating-current path control circuit. During the maintaining the current in the primary winding, the method can include initiating a spark in a spark plug included in the ignition circuit, the initiating the spark including controlling an amount of energy delivered from the primary winding to a secondary winding of the ignition coil.

It is made possible to control ignition appropriately.

An ignition device 1 for an internal combustion engine includes a spark coil 50 including: a primary side coil 51 connected to a direct current power supply 40 and a secondary side coil 52 magnetically connected to the primary side coil 51 and connected to an ignition plug 60; a switch element 30 that performs switching between energization and interruption of primary current I1 to the primary side coil 51; and a switch element controlling circuit 20 that controls the switch element 30 on the basis of an ignition controlling signal 51 supplied from an ECU 10. A turn-on delay adjustment circuit 22 that delays a control timing of the switch element 30 is disposed between the ECU 10 and the switch element 30 such that first resonance noise generated due to interruption of the primary current I1 to the primary side coil 51 is reduced.

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.