Provided is a control device of a fuel injection device which can stabilize a behavior of a valve even when a voltage of a voltage source varies, and can reduce a deviation of an injection amount. A control device 150 of a fuel injection device 101 includes a valve 214, a coil 205 which generates a magnetic attraction force to attract a movable member 202 which drives the valve 214, and a voltage source. The fuel injection device 101 applies a voltage to the coil 205 on the basis of an injection pulse, causes a drive current to flow to the coil 205 until the current becomes a maximum current to attract the movable member 202, and drives the valve 214 to inject fuel. The drive current flowing to the coil 205 or a voltage of the voltage source is detected before the injection pulse is stopped. In a case where the detected drive current or the voltage is equal to or less than a setting, a width of the injection pulse or an injection pulse different from the injection pulse is corrected to be long.

A controller causes a calculation device to perform calculation that determines an operation of a moving object and generates digital signals that define the operations of actuators. The generated digital signals are output to a digital signal transmission path by a signal bus control IC. ICs attached to the actuators obtain digital signals that define the operations of the actuators from the digital signal transmission path and generate control signals for the actuators based on the operations defined by the digital signals.

An energization instruction switch switches energization instruction signals to instruct energization of fuel injection valves. A first cylinder designation switch designates one of the energization instruction signals to designate a valve closing detection cylinder. A valve closing detection unit monitors downstream voltage of the fuel injection valve to detect occurrence of an inflection point in change of the downstream voltage to detect a valve closing. A second cylinder designation switch designates one of the downstream voltages and designates the valve closing detection cylinder. A valve closing time measuring unit measures a valve closing time, which is from a switching timing of the energization instruction signal from ON to OFF to a valve closing detection timing, for injection of the valve closing detection cylinder. A valve closing time learning unit learns the valve closing time measured by the valve closing time measuring unit.

A method is provided for controlling a solenoid actuated fuel injector having a solenoid actuator which moves a pintle and needle arrangement such that the needle moves away from a valve seat to an open position and also includes circuitry which applies chopped hysteresis control subsequent to an energisation phase. The method includes a) obtaining a signal of the current or voltage across the solenoid; b) analyzing the voltage or current to detect a chopped hysteresis pulse; c) determining the time point of the end of said chopped hysteresis pulse; and d) applying a braking pulse to the solenoid, the timing of which is dependent on the results of step c).

An injection control device controls a solenoid in a fuel injection valve. The injection control device includes a transistor on an upstream side of a first power supply path to the solenoid, and a transistor on an upstream side of a second power supply path to the solenoid. The injection control device has another transistor with a body diode arranged in parallel at a position between an upstream terminal of the solenoid and ground. The injection control device also includes a transistor on the downstream side of the first and second power supply paths. A drive controller in the injection control device drives the solenoid to an open position by switching ON the transistor on the downstream side and one of the transistors on the upstream side power supply paths.

An injection control device controls a drive of a solenoid in a high pressure pump for pressurizing fuel to an internal combustion engine. The injection control device includes a transistor on an upstream side of a power supply path from a direct current power supply line to the solenoid and a transistor provided on a downstream side of the power supply path. The injection control device further includes a diode at a position between an upstream terminal of the solenoid and ground, a transistor arranged in parallel with the diode, and a drive controller. The drive controller drives the solenoid to an open position by switching ON the transistors on the upstream and downstream sides of the power supply path.

An energization instruction switch switches energization instruction signals to instruct energization of fuel injection valves. A first cylinder designation switch designates one of the energization instruction signals to designate a valve closing detection cylinder. A valve closing detection unit monitors downstream voltage of the fuel injection valve to detect occurrence of an inflection point in change of the downstream voltage to detect a valve closing. A second cylinder designation switch designates one of the downstream voltages and designates the valve closing detection cylinder. A valve closing time measuring unit measures a valve closing time, which is from a switching timing of the energization instruction signal from ON to OFF to a valve closing detection timing, for injection of the valve closing detection cylinder. A valve closing time learning unit learns the valve closing time measured by the valve closing time measuring unit.

A fuel injection control device is for a fuel injection system including a fuel injection valve for injecting a fuel in an internal combustion engine. The fuel injection system is configured to perform multiple-stage injection for injecting fuel multiple times in one combustion cycle. The fuel injection control device includes an information acquisition unit to acquire a parameter, which indicates an influence of a pre-stage injection on a post-stage injection, in the pre-stage injection and the post-stage injection subsequent to the pre-stage injection in the multi-stage injection. The fuel injection control device further includes a correction unit to correct a mode of the post-stage injection based on the parameter.

A valve controller and method for controlling a valve having a solenoid are disclosed, including receiving a least one input signal, detecting a first edge of the at least one signal and in response to the detection activating the valve. Activating the valve includes activating the valve in a rise-to-peak phase during which the valve is opened, a hold phase following the rise-to-peak phase during which the valve remains open and a current level of the valve is less than a current level of the valve during the rise-to-peak phase, and an ending-of-activation phase following the hold phase during which current ripple in the valve is less than the current ripple in the valve during the hold phase.

An input protection circuit (200) and associated method are disclosed for protecting a circuit input (V.sub.INP) from positive and negative overvoltages at an input voltage (V.sub.IN) with a high-voltage PMOSFET (P1) having a gate, a drain connected across a zener diode (ZD1) to the gate, and a source connected to receive an input voltage; a blocking FET (N1) having a gate connected to a power supply voltage, a drain connected across a zener diode (ZD2) to the power supply voltage, and a source connected to the gate of the high-voltage PMOSFET; a high-voltage NMOSFET (N3) having a gate connected to the power supply voltage, a source providing the protected output voltage and connected across a zener diode (ZD3) to the gate, and a drain connected to a source follower node and a level shifter circuit (214) connected between the drain of the high-voltage PMOSFET and the source follower node.