Abstract: At the time of drop of an injector current of an internal combustion engine controller, the drop is performed quickly while heat generation of a drive circuit is suppressed, and valve closing response speed of the injector is enhanced.

Abstract: Disclosed is an electromagnetic valve driving circuit capable of reducing a load of a booster circuit. A boost driving FET 202 is connected to a route formed between the booster circuit 100 and a first terminal of an injector 3. A battery-side driving FET 212 and a battery protection diode Db are connected to a route formed between a positive-polarity side of a power supply and the first terminal of the injector 3. A freewheeling diode Df is connected at a first terminal thereof to a portion between the first terminal of the injector 3 and the battery protection diode Db, and at a second terminal thereof to a grounding side of the power supply. An injector downstream-side driving FET 220 is connected to a route formed between the second terminal of the injector 3 and the grounding side of the power supply.

Abstract: The present invention realizes an injector drive circuit capable of providing high output power of a boost convertor while suppressing increases in size and cost thereof. An injector energizing circuit 200 includes an FET 2 which applies a high voltage 100a generated by a boost convertor 100 to an injection valve 20. The boost convertor 100 includes an input side capacitor 103, a boosting FET 105, a boost coil 104, a boost diode 106, and FETs 108 and 109 provided in association with a negative pole of an output side capacitor 107. During a period in which the high voltage 100a is applied to the injection valve 20, a gate signal 108a of the FET 108 is turned ON and a gate signal 109a of the FET 109 is turned OFF. Consequently, the boosting FET 105 performs a switching operation to turn OFF the gate signal 108a of the FET 108 and turn ON the gate signal 109a of the FET 109 during a period for charging into the output side capacitor 107.

Abstract: At the time of drop of an injector current of an internal combustion engine controller, the drop is performed quickly while heat generation of a drive circuit is suppressed, and valve closing response speed of the injector is enhanced.

Abstract: Disclosed is an electromagnetic valve driving circuit capable of reducing a load of a booster circuit. A boost driving FET 202 is connected to a route formed between the booster circuit 100 and a first terminal of an injector 3. A battery-side driving FET 212 and a battery protection diode Db are connected to a route formed between a positive-polarity side of a power supply and the first terminal of the injector 3. A freewheeling diode Df is connected at a first terminal thereof to a portion between the first terminal of the injector 3 and the battery protection diode Db, and at a second terminal thereof to a grounding side of the power supply. An injector downstream-side driving FET 220 is connected to a route formed between the second terminal of the injector 3 and the grounding side of the power supply.

Abstract: The present invention realizes an injector drive circuit capable of providing high output power of a boost convertor while suppressing increases in size and cost thereof. An injector energizing circuit 200 includes an FET 2 which applies a high voltage 100a generated by a boost convertor 100 to an injection valve 20. The boost convertor 100 includes an input side capacitor 103, a boosting FET 105, a boost coil 104, a boost diode 106, and FETs 108 and 109 provided in association with a negative pole of an output side capacitor 107. During a period in which the high voltage 100a is applied to the injection valve 20, a gate signal 108a of the FET 108 is turned ON and a gate signal 109a of the FET 109 is turned OFF. Consequently, the boosting FET 105 performs a switching operation to turn OFF the gate signal 108a of the FET 108 and turn ON the gate signal 109a of the FET 109 during a period for charging into the output side capacitor 107.

Abstract: A fuel injection valve driving method includes control of an overexciting current and a holding current supplied to the fuel injection valve in accordance with a target fuel supply pressure as obtained from an operating condition. Thereby the opening and holding of the open position of the fuel injection valve is controlled.

Abstract: A fuel injection valve driving method by means of a fuel supply pressure detector involves various types of delay including a response lag of the fuel supply pressure detector, a lag produced by a noise filter of a signal processing circuit, and a lag produced by a software filter provided in an arithmetic unit. These delay factors produce a lag in increasing the value of current supplied to the fuel injection valve despite the fact that an actual fuel supply pressure is already high. Then, no attractive force for overcoming the fuel supply pressure is generated in the fuel injection valve, so that a condition arises in which fuel is not injected due to the fuel injection valve not being opened.