Abstract: An EGR valve position control system includes an EGR valve manager responsive to an EGR valve command to drive an EGR valve actuator. The EGR valve manager is operable to schedule control gains as a function of valve actuation direction to provide for faster response during valve closing events. Valve closing events are also staged such that a large valve position step is followed by a steady ramp to the valve closed position to thereby prevent damage to the valve and/or valve seat. The EGR valve manager further includes a prioritized switching feature for strategically switching between closed and open loop control modes, and a forward gain adjustment feature responsive to battery voltage to maintain constant system DC gain under changing battery voltage conditions.

Abstract: An EGR valve position control system includes an EGR valve manager responsive to an EGR valve command to drive an EGR valve actuator. The EGR valve manager is operable to schedule control gains as a function of valve actuation direction to provide for faster response during valve closing events. Valve closing events are also staged such that a large valve position step is followed by a steady ramp to the valve closed position to thereby prevent damage to the valve and/or valve seat. The EGR valve manager further includes a prioritized switching feature for strategically switching between closed and open loop control modes, and a forward gain adjustment feature responsive to battery voltage to maintain constant system DC gain under changing battery voltage conditions.

Abstract: A load driver system for integrally controlling the flow of current through a number of inductive loads of an internal combustion engine, particularly the flow of current through a fuel injector solenoid and an engine brake solenoid during the operation of an engine cylinder, is provided. In one embodiment of the load driver system, a single multiplexed high side driver is connected to inputs of both solenoids, and separate low side drivers are connected to outputs of each of the solenoids. In an alternative embodiment, separate high side drivers are connected to inputs of each of the solenoids, and a single multiplexed low side driver is connected to the outputs of the solenoids.

Abstract: Circuitry (20) for activating fuel injectors (50) of an internal combustion engine including a plurality of switching circuits (60) for turning on and off associated hybrid power circuits (80). The hybrid power circuits (80) communicate the increased level of voltage generated by a single boost voltage generator (70) to particular injectors (50).

Abstract: A switching type control unit (20) for activating fuel injectors (50) of an internal combustion engine. The control unit (20) including a plurality of switching circuits (60) for turning on and off associated hybrid power circuits (80). The hybrid power circuits (80) communicate the increased level of voltage generated by a single boost voltage generator (70) to particular injectors (50).

Abstract: A driver circuit, having boost and hold modes of operation, for a solenoid having a high and a low impedance coil wherein the coils are so situated such that their respective magnetic fields are additive and wherein the driver circuit is responsive to input metering pulse width signals and includes means for modifying the duration of each pulse width signal to generate a boost pulse signal to excite the low impedance coil in correspondence with the variations in the battery voltage. The driver circuit further includes means for permitting the current flowing through the low impedance coil into flow into a high impedance coil and means for regulating the value of current flowing therethrough at a determinable value. The driver circuit further includes means for reducing the current droop occurring upon the transition from the boost mode of operation to the hold mode of operation.

Abstract: A method and apparatus for controlling the various functions of an internal combustion engine using a program-controlled microprocessor having a memory preprogrammed with various control laws and associated control schedules receives information concerning one or more engine-operating parameters such as manifold absolute pressure, throttle position, engine coolant temperature, air temperature, engine speed or period and the like. These parameters are sensed and then supplied to input circuits for signal conditioning and conversion into digital words usable by the microprocessor. The microprocessor system computes a digital command word indicative of a computer-commanded engine control operation and output circuitry responds to predetermined computer-generated commands and to the computed digital command words for converting them to corresponding pulse-width control signals for controlling such engine operations as fuel-injection ignition timing, proportional and/or on-off EGR control, or the like.

Abstract: A signal conditioning circuit for the output of a magnetic position sensor is disclosed. The magnetic sensor generates a total output signal that increases as a function of the rotational velocity of the sensor with a spurious noise component that is a relatively constant percentage of the actual signal voltage over the speed range. In a preferred embodiment, the signal conditioning circuit discriminates between the noise component and the signal component by comparing the total signal to a variable threshold only after a positive going zero cross. The variable threshold is generated as a function of the peak amplitude of the total signal. In a second embodiment the signal conditioning circuit includes gain control means which varies the amplitude of the total output signal as a function of its peak to maintain the threshold above the noise component.

Abstract: A method and apparatus for controlling the various functions of an internal combustion engine using a program-controlled microprocessor system having a memory preprogrammed with various control laws and associated control schedules receives information concerning one or more engine-operating parameters such as manifold pressure, throttle position, engine coolant temperature, air temperature, engine speed or period, and the like. These parameters are sensed and then supplied to input circuits for signal conditioning and conversion into digital words usable by the microprocessor system. The microprocessor system computes a digital command word indicative of a computer-commanded engine control operation and output circuitry responds to predetermined computer-generated commands and to the computed digital command word for converting them to corresponding pulse-width control signals for controlling such engine operations as fuel-injection, ignition timing, proportional and/or on-off EGR control, and the like.

Abstract: A method and apparatus for controlling the various functions of an internal combustion engine using a program controlled microprocessor having a memory preprogrammed with various control laws and associated control schedules receives information concerning one or more engine-operating parameters such as manifold absolute pressure, throttle position, engine coolant temperature, air temperature, engine speed or period and the like. These parameters are measured and their value or status is supplied to input circuits for signal conditioning and conversion into digital words usable by the microprocessor.

Abstract: A signal conditioning circuit for the output of a magnetic position sensor is disclosed. The magnetic sensor generates a total output signal that increases as a function of the rotational velocity of the sensor with a spurious noise component that is a relatively constant percentage of the actual signal voltage over the speed range. In a preferred embodiment, the signal conditioning circuit discriminates between the noise component and the signal component by comparing the total signal to a variable threshold only after a positive going zero cross. The variable threshold is generated as a function of the peak amplitude of the total signal. In a second embodiment the signal conditioning circuit includes gain control means which varies the amplitude of the total output signal as a function of its peak to maintain the threshold above the noise component.