Igniter
AssigneeRohm Co., Ltd.
InventorKatsuya OBE
Life of this patent
Estimating the term…
Abstract
An igniter includes a switch element and a switch control apparatus. An ignition signal IGT is input to an input line of the switch control apparatus. A high-frequency filter removes high-frequency noise from the input line. A voltage comparator compares an output voltage VFIL of the high-frequency filter with a reference voltage VREF, so as to generate a judgment signal SDET. A driving stage controls an on/off switching operation of the switch element according to the judgment signal SDET. An off-state dead-time circuit prohibits the switch element from turning off during a predetermined dead time after the judgment signal SDET transits to a negated level that corresponds to the off state of the switch element.
Claims7
An igniter comprising:
- a switch element connected to a primary coil of an ignition coil;
- and
- a switch control apparatus that controls the switch element according to an ignition signal supplied from an ECU (Engine Control Unit),
- wherein the switch control apparatus comprises:
- an input line via which the ignition signal is supplied;
- a filter that removes high-frequency noise from the input line;
- a voltage comparator that compares an output voltage of the filter with a reference voltage, so as to generate a judgment signal;
- a driving stage that controls an on/off switching operation of the switch element according to the judgment signal;
- and
- an off-state dead-time circuit that prohibits the driving stage from turning off the switch element during a predetermined dead time after the judgment signal transits to a negated level that corresponds to an off state of the switch element.
An igniter comprising:
- a switch element connected to a primary coil of an ignition coil;
- and
- a switch control apparatus that controls the switch element according to an ignition signal supplied from an ECU (Engine Control Unit),
- wherein the switch control apparatus comprises:
- an input line via which the ignition signal is supplied;
- a filter that removes high-frequency noise from the input line;
- a voltage comparator that compares an output voltage of the filter with a reference voltage, so as to generate a judgment signal;
- a driving stage that controls an on/off switching operation of the switch element according to the judgment signal,
- and wherein the switch element is maintained in an off state during a predetermined dead time after the judgment signal transits to a negated level that corresponds to an off state of the switch element.
A control method for an ignition coil connected to an spark plug, the control method comprising:
- generating an ignition signal by means of an ECU (Engine Control Unit), which is an instruction to ignite the spark plug;
- removing high-frequency noise from the ignition signal by means of a filter;
- comparing an output voltage of the filter with a reference voltage, so as to generate a judgment signal;
- controlling an on/off switching operation of a switch element connected to a primary coil of the ignition coil according to the judgment signal;
- and
- prohibiting the switch element from turning off during a predetermined dead time after the judgment signal transits to a negated level that corresponds to an off state of the switch element.
Dependencies are inferred from the claim text.