An object is to reduce the required numbers of connector pins and A/D converters, without degrading the detection accuracy. There is provided an ignition apparatus which includes: ignition plugs provided for multiple cylinders; an ignition coil provided for each cylinder, and having a primary coil and a secondary coil magnetically coupled to the primary coil and connected to the ignition plug; switching devices each for switching between application and shut-off of current to the primary coil; a primary-voltage-signal separator provided for each cylinder, for inputting thereto a voltage of the primary coil and outputting the voltage as a primary signal; a primary-signal combiner for electrically combining together each primary signal corresponding to each cylinder, to thereby output a composite primary signal; and a primary-voltage-information detector for inputting thereto the composite primary signal, to thereby output primary voltage information of each cylinder.

Disclosed is an ignition drive module with stable performance and reliable function, which comprises a module signal input end, a voltage input end, a module signal output end, a comparator. One end of the comparator is connected to the module signal input end, and the other end is connected to a comparison resistance R that is grounded. The ignition drive module further comprises a maximum dwell timer module connected to the comparator, a logical judgment module connected to the comparator, and an IGBT module connected to the logical judgment module which receives the signals from the maximum dwell timer module and the comparator to determine whether to activate the IGBT module. The output end of the IGBT module is connected to the module signal output end.

A semiconductor apparatus is provided, including a power semiconductor element, a cutoff condition detection portion which detects whether a predetermined cutoff condition is met, a reset portion which outputs a reset signal that instructs to reset during a predetermined period in response to an input of the control signal turning the power semiconductor element on, a latch portion which is reset in response to the reset signal and latches that an occurrence of the cutoff condition is detected after the reset, a cutoff circuit which controls the gate of the power semiconductor element to be at an OFF potential in response to the latching of the occurrence of the cutoff condition by the latch portion, and a prevention circuit which prevents the gate of the power semiconductor element from being at an ON potential during a period of reset of the latch portion even if the cutoff condition is met.

Provided is a switch apparatus including a conductor; a switching device that contacts the conductor on a first surface and switches between a first terminal on the first surface side and a second terminal on a second surface side that is opposite to the first surface; and a control device that contacts the conductor on a third surface and includes a control circuit of the switching device provided on a fourth surface side opposite to the third surface and a first withstand voltage structure that protects the control circuit from excessive voltage added to the conductor. By providing the withstand voltage structure in the control device, it is possible to protect the control circuit.

An object is to reduce the required numbers of connector pins and A/D converters, without degrading the detection accuracy. There is provided an ignition apparatus which includes: ignition plugs provided for multiple cylinders; an ignition coil provided for each cylinder, and having a primary coil and a secondary coil magnetically coupled to the primary coil and connected to the ignition plug; switching devices each for switching between application and shut-off of current to the primary coil; a primary-voltage-signal separator provided for each cylinder, for inputting thereto a voltage of the primary coil and outputting the voltage as a primary signal; a primary-signal combiner for electrically combining together each primary signal corresponding to each cylinder, to thereby output a composite primary signal; and a primary-voltage-information detector for inputting thereto the composite primary signal, to thereby output primary voltage information of each cylinder.

In an ignition apparatus, a deterioration determination circuit performs a deterioration determination task of (i) monitoring an absolute increase in a temperature parameter during a predetermined deterioration detection period that has been started since an energization command signal being inputted to a control circuit, and (ii) performing a comparison between the absolute increase in the temperature parameter and a predetermined deterioration detection threshold to thereby determine whether a level of deterioration of a switching circuit is within an acceptable level.

A multi-charge ignition system including a spark plug control unit (13) adapted to control at least two coil stages so as to successively energise and de-energise said coil stage(s) to provide a current to a spark plug, said two stages comprising a first transformer (T1) including a first primary winding (L1) inductively coupled to a first secondary winding (L2); a second transformer (T2) including a second primary winding (L3) inductively coupled to a second secondary winding (L4); a first switch Q1 electrically connected between the low side of the first primary winding L1 and the low side/earth, a second switch Q2 having a connection to the low side of the second primary winding L3; and including a first diode D1 electrically connected between the low side of said first secondary winding L3 and ground, and a second diode D2 connected to a point between the low side of said second secondary winding L4 and ground and, including means to measure the voltage at a first connection point (203a) between the first switch and the low side of L1 and/or the voltage at a second connection (203b) point between the second switch and the low side of L3; and means to control the operation of the system dependent upon said measured voltages.

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.

Disclosed is an ignition drive module with stable performance and reliable function, which comprises a module signal input end, a voltage input end, a module signal output end, a comparator. One end of the comparator is connected to the module signal input end, and the other end is connected to a comparison resistance R that is grounded. The ignition drive module further comprises a maximum dwell timer module connected to the comparator, a logical judgment module connected to the comparator, and an IGBT module connected to the logical judgment module which receives the signals from the maximum dwell timer module and the comparator to determine whether to activate the IGBT module. The output end of the IGBT module is connected to the module signal output end.

In an ignition apparatus, a deterioration determination circuit performs a deterioration determination task of (i) monitoring an absolute increase in a temperature parameter during a predetermined deterioration detection period that has been started since an energization command signal being inputted to a control circuit, and (ii) performing a comparison between the absolute increase in the temperature parameter and a predetermined deterioration detection threshold to thereby determine whether a level of deterioration of a switching circuit is within an acceptable level.