Abstract: A switching power converter includes: a power stage circuit, including at least one transistor which is configured to operably switch an inductor to convert an input power to an output power; and an active EMI filter circuit, including at least one amplifier, wherein the at least one amplifier is configured to operably sense a noise input signal which is related to a switching noise caused by the switching of the power stage circuit, and amplify the noise input signal to generate a noise cancelling signal, wherein the noise cancelling signal is injected into an input node of the switching power converter, so as to suppress the switching noise and thus reducing EMI, wherein the input power is provided through the input node to the power stage circuit.

Abstract: A switching power converter includes: a power stage circuit, including at least one transistor which is configured to operably switch an inductor to convert an input power to an output power; and an active EMI filter circuit, including at least one amplifier, wherein the at least one amplifier is configured to operably sense a noise input signal which is related to a switching noise caused by the switching of the power stage circuit, and amplify the noise input signal to generate a noise canceling signal, wherein the noise canceling signal is injected into an input node of the switching power converter, so as to suppress the switching noise and thus reducing EMI, wherein the input power is provided through the input node to the power stage circuit.

Abstract: Apparatus, systems, and/or methods are disclosed relating to a welding-type power supply with a pre-regulator circuit configured to provide a pre-regulated direct current (DC) bus at two or more voltage levels, responsive to various operating conditions. In some examples, the pre-regulator circuit may be configured to provide a pre-regulated DC bus voltage at one voltage level for certain input line voltages, weld processes, and/or target weld output levels, and at another voltage level for other input line voltages, weld processes, and/or target weld output levels. In some examples, the pre-regulator circuit may be configured to provide a pre-regulated DC bus voltage for certain input line voltages, weld processes, and/or target weld output levels and an unregulated DC bus voltage at other input line voltages, weld processes, and/or target weld output levels.

Abstract: A controller for a linear solenoid valve is configured to: calculate an average value of an exciting current within a period including a natural number multiple of the dither cycle as an average current value; execute a feedback control on a control value of the pulse width modulation signal such that a target value of the exciting current and the average current value match; and calculate a dither correction amount by multiplying a ratio between the control value of the pulse width modulation signal obtained by the feedback control and the average current value by a dither current value that is a current value corresponding to the dither correction amount and calculating the dither correction amount such that an increase in the exciting current due to the dither correction amount is canceled out by a decrease in the exciting current due to the dither correction amount within one dither cycle.

Abstract: A coil arrangement has an electrical coil and an armature movable between a first and second end positions, an electronic switch switchable between at least two switch states, a control and monitoring circuit for producing a switching signal actuating the electronic switch and an operating circuit for providing an operating voltage and an electrical current measurement signal representing an electrical current flowing as a function of time in a coil electrical current circuit formed with the coil. The control and monitoring circuit is adapted to detect whether an inductance of the coil has a dependence on the switching signal as a function of time. The electromechanical has a first switch contact movable between first and second switch positions, a second switch contact and a coil arrangement of the invention, while the measurement transmitter has also a measuring circuit for receiving at least one transducer signal.

Abstract: A circuit breaker characteristic monitoring device monitors the operation of a circuit breaker to estimate the amount of consumption of a movable contact and fixed contacts included in the circuit breaker. The device includes an operating time measurement unit to measure at least one of closing time, which is the time required for the circuit breaker to be closed after starting a closing operation, and opening time, which is the time required for the circuit breaker to be open after starting an opening operation, and a contact consumption amount estimation unit to estimate the amount of consumption of the movable contact and the fixed contacts on the basis of the result of measurement performed by the operating time measurement unit and travel speed of the movable contact during the closing operation or the opening operation for which the measurement result is obtained.

Abstract: A controller according to the present disclosure includes a target current controller, a dither controlling unit, an output-duty generating unit, and a Pulse-Width-Modulation-pulse (PWM-pulse) converting unit. The dither controlling unit generates a dither duty for providing, to a target current duty of a load, a dither having predetermined dither period. The target current controller calculates, for each predetermined feedback period, an average value of a feedback current from the load and generates the target current duty based on the average value. The output-duty generating unit generates an output duty obtained by adding the dither duty generated by the dither controlling unit to the target current duty generated by the target current controller. The PWM-pulse converting unit converts the output duty generated by the output-duty generating unit to PWM pulses.

Abstract: An ECU, which applies a predetermined high voltage for valve-opening operation and subsequently applies a predetermined low voltage to maintain the valve-opening and thus energizes a fuel injector for fuel injection by the fuel injector, includes a current detection section that detects an energizing current flowing through the fuel injector, a drive IC that, after start of energization of the fuel injector, when a detection current detected by the current detection section arrives at a beforehand determined target peak value, switches the voltage applied to the fuel injector from the high voltage to the low voltage, and a microcomputer that calculates a slope of change in current in the detection current while the high voltage is applied to the fuel injector, and performs correction processing to correct shift of a peak point of an actual current flowing through the fuel injector based on the slope of change in current.

Abstract: A calculation control circuit unit 110A is provided with a microprocessor 111, an auxiliary control circuit unit 190A, and a high-speed A/D converter 115 to which the detection signals of excitation currents for electromagnetic coils 81 through 84 are inputted; based on an valve-opening command signal generated by the microprocessor 111 and excitation-current setting information, the auxiliary control circuit unit 190A opening/closing-controls power supply control opening/closing devices by use of a numeral value comparator and a dedicated circuit unit, and monitors and stores at least one of the peak value of a rapid excitation current and a peak current reaching time; the microprocessor 111 performs correction control with reference to the monitoring storage data, and implements fuel injection control while reducing a rapid control load on the microprocessor 111.

Abstract: An electrical contactor for switching a load current having an AC waveform, has a fixed electrical contact, a movable electrical contact, an actuator arrangement having a drive coil drivable for opening and closing the movable and fixed electrical contacts, and a power supply having a controller for outputting truncated-waveform drive pulses to the electrical actuator arrangement, so as to prevent contact separation prior to peak load current.

Abstract: A current control device sets a target current value of a solenoid, and sets a duty ratio of a PWM signal outputted to a drive circuit of a solenoid based on the target current value. The target current value is a value that periodically varies in a dither period longer than a PWM period of the PWM signal. A setting period of the target current value and a setting period of the duty ratio are shorter than the dither period. As compared with a configuration where the duty ratio is set in the dither period, a time period from a time a basic current value is changed to a time the duty ratio is renewed is shortened. A operation responsiveness of a movable core of the solenoid improves.

Abstract: A method, device, and control unit for controlling an actuator in open loop, particularly for a valve, preferably for a gas-exchange valve of an internal combustion engine, having at least one control valve for opening the valve and one control valve for closing the valve, each of the control valves being capable of being driven by at least one drive pulse whose duration determines a position on the positioning travel of the valve. The valve is opened/closed in one lift and/or a plurality of partial lifts and at least one drive pulse is assigned to each lift and/or each partial lift, and the valve is assigned at least one transducer which generates a signal that discloses values of a discrete positioning travel of the valve and of an assigned time and/or of a discrete instant and of an assigned positioning travel. The method for controlling the actuator includes: a. Starting of a drive pulse having a setpoint duration of the drive pulse for opening and/or closing the valve, b.

Abstract: A circuit for controlling an inductive load, e.g. of a fuel injection valve, includes supply terminals for supplying a voltage, output terminals for connecting the load, and a detection device which is connected to at least one of the output terminals and is used for detecting the point in time at which the operation of the load is discontinued and/or detecting at least one fault case during a non-operational phase of the load. In order to render the detection process more reliable while using less circuitry, the detection device encompasses a current mirror with a first current source and a second current source. The current first is connected to one of the two output terminals during a detection phase. The current supplied by the second current source is evaluated as a signal of the detected result.

Abstract: An electromechanical device includes a rotor, a stator having a magnetic coil, a sensor adapted to detect an electric angle of the rotor, a control section adapted to perform a PWM drive on the magnetic coil based on a signal from the sensor, a resistor connected in series to the magnetic coil when measuring temperature of the electromechanical device, and a voltage measurement section adapted to measure a voltage between both ends of the resistor, and the control section calculates an electric resistance of the magnetic coil using the voltage between the both ends of the resistor measured by the voltage measurement section, and then determines the temperature of the magnetic coil using the electric resistance of the magnetic coil in a measurement period in which application of a drive voltage to the magnetic coil is stopped in the PWM drive.

Abstract: In an embodiment according to the invention, the controller for a solenoid in an electromechanical lock is arranged to generate motion power to move the solenoid plunger and holding power to hold the solenoid plunger in place so that the motion power generated consists of a higher power level and a lower power level that are alternating.

Abstract: A driving device for a piezoelectric actuator supplies charges and discharges the piezoelectric actuator through a charging switch and a discharging switch, respectively. The charging switch is repeatedly turned on and off thereby to charge and expand the piezoelectric actuator. The discharging switch is repeatedly turned on and off thereby to discharge and contract the piezoelectric actuator. The discharging switch is kept ON especially during a period from when the discharging switching control is terminated to when the charging switching control is started next. Thus, the piezoelectric voltage at the start of the next driving can be made substantially 0V.

Abstract: A solenoid valve driving apparatus includes switching means for ON/OFF-controlling application of a direct current voltage to a solenoid of a solenoid valve, and signal outputting means. A first period and a consecutive second period are set as a valve opening operation period of the solenoid valve. When the signal outputting means outputs the PWM signal to the switching means, a duty ratio of the output signal is set to be higher in the second period than in the first period so that a power supplied to the solenoid is larger in the second period than in the first period. As a result, a valve opening operation is performed in the solenoid valve reliably, and loud noise generation during the valve opening operation is suppressed.

Abstract: A first voltage-to-current converter converts a difference voltage between a command voltage and a reference voltage into a current. A second voltage-to-current converter converts a difference voltage between a positive output terminal and a negative output terminal of a PWM drive apparatus into a current. A low-pass filter is connected to a connection point between an output terminal of the first voltage-to-current converter and an output terminal of the second voltage-to-current converter. An amplifier amplifies a difference voltage between a voltage at the connection point and a reference voltage. A PWM modulator PWM-modulates an output voltage of the amplifier. A drive section drives a load in accordance with an output signal of the PWM modulator.

Abstract: A solenoid-operated valve actuating controller actuates a solenoid-operated valve by energizing an actuating coil of the solenoid-operated valve in a rated mode, enough to move a movable member in the actuating coil, during a first period. Further, the actuating coil is energized in a power saving mode, during a second period after the first period. The solenoid-operated valve actuating controller has a timer circuit for setting the first period, an oscillating circuit for energizing the actuating coil in the power saving mode during the second period, and a control circuit for stopping an oscillating operation of the oscillating circuit during the first period based on an output signal from the timer circuit, and for energizing the actuating coil in the rated mode.

Abstract: A method for operating an inductive load, which is operated in a motor vehicle with electric voltages of different magnitudes, is provided, a current rise in the inductive load being influenced by selecting pulse lengths and pulse pauses of the electric voltage.

Abstract: A power switching control apparatus for acquiring pieces of making operation time information of individual phase switches more precisely according to loads and making instants. Making operation time information detecting means outputs the making operation time information of at least one of individual phase switches on the basis of the motion of the movable contact of the phase switch, and outputs the making operation time information of at least another of the individual phase switches on the basis of the phase current of the phase switch. Moreover, the making operation time information detecting means outputs the making operation time information ITA, ITB and ITC of an A-phase switch, a B-phase switch and a C-phase switch individually on the basis of either the detected output of a contact operation sensor and the detected output of a phase current sensor.

Abstract: Methods and systems provide pulsed-power to a load utilizing high temperature superconductors (HTS) within multiple pulsed-power devices. According to embodiments described herein, each pulsed-power device includes a HTS mounted on a rotor and an armature coil mounted on a stator. The rotor is positioned to allow a magnetic field within the HTS to induce a voltage in the armature coil when the rotor is rotating and to allow a magnetic field created by passing current through the armature coil to charge the HTS. Current created from the operation of a first pulsed-power device is routed to the armature coil in a second pulsed-power device to charge the associated HTS to a higher value. Subsequently, the second pulsed-power device is operated to produce current that is used to further charge the HTS in the first pulsed-power device. This bootstrapping procedure is repeated until all HTSs are fully charged.

Abstract: A microprocessor-based control system is provided that comprises a plurality of latching relays, at least some of which may be connected in parallel. A momentary application of voltage of a first polarity or a second polarity to the coil causes the latching relay contacts to switch and remain in an open or closed state respectively. An individual relay driver circuit is provided for a corresponding latching relay or set of latching relays, and has a first and second switch that respectively apply a voltage or a ground connection to a first end of each coil corresponding to the individual relay driver. The control system includes a common relay driver connected to at least one of the latching relays for each relay drive circuit, and has a first and second switch that respectively apply a voltage or a ground connection to the second end of the latching relay coils connected to the common relay driver circuit.

Abstract: The present invention refers to an apparatus for driving an electromagnetic load. The apparatus comprises a power stage comprising at least one first and one second transistor half-bridge and the electromagnetic load is arranged between the first and the second half-bridge. The apparatus comprises a first and a second device suitable for driving in linear modality respectively the first and the second half-bridge and another device suitable for driving in pulse width modulation modality the first half-bridge, first switch means suitable for connecting the first half-bridge to the first device or to the other device in response to a control signal, second switch means suitable for connecting the second half-bridge to the second device in response to the control signal.

Abstract: The present invention relates to a device and a method for utilizing a control module as an interfaced control of a dually configured AC/DC control coil comprising monitoring a coil voltage of the control coil, determining if the coil voltage is greater than a predetermined dropout voltage, and determining if the coil voltage is greater than a predetermined pickup voltage. Further, a generated astable pulse is reset in the event that the coil voltage is determined to be less than the predetermined dropout voltage.

Abstract: An electromagnetic actuator comprises a yoke, a core, at least two windings and switching means of the windings from a series position to a parallel position and vice-versa. It comprises control means comprising regulating means of the electric current flowing in the windings. The control means comprise inrush means controlling the voltage supplied to the windings during a closing operation, and controlling the switching means to place the windings in parallel mode. The control means also comprise holding means controlling the current supplied to the windings during a holding operation of the actuator in the closed position and controlling the switching means to place the windings in series mode.

Abstract: A driving device for a piezoelectric actuator supplies charges and discharges the piezoelectric actuator through a charging switch and a discharging switch, respectively. The charging switch is repeatedly turned on and off thereby to charge and expand the piezoelectric actuator. The discharging switch is repeatedly turned on and off thereby to discharge and contract the piezoelectric actuator. The discharging switch is kept ON especially during a period from when the discharging switching control is terminated to when the charging switching control is started next. Thus, the piezoelectric voltage at the start of the next driving can be made substantially 0V.

Abstract: For the purposes of a determination of a fuel vapor loading level of a fuel vapor retention system of a combustion engine, an opening level of a valve of the fuel vapor retention system is increased in steps or continuously during a determination phase. Furthermore, the valve is activated at most a predefined first period prior to a start of the determination phase by a conditioning pulse at least whenever the valve was closed previously for a second period that is longer than a predefined threshold value. The conditioning pulse is generated in such a way that the valve definitely opens at most for a predefined opening period and then closes again.

Abstract: A potential of an end of the coil is inputted to a plate-OFF detecting portion which detects OFF-tendency in which a plate of a relay is about to get apart from a head of a core of the relay. When the OFF-tendency is detected, a coil current for supplying a coil of the relay is set to a first current value with which a plate of an electromagnetic relay is drawn and a movable contact of the relay comes in contact with a fixed contact of the relay. When an external disturbance ends, the coil current is returned to a second current value, which is smaller than the first current value, so that the movable contact and the fixed contact are kept in contact with each other.

Abstract: There is described a method of operating a device (1) controlling electric actuators (3), and having a pair of input terminals (4, 5) connected to an electric energy source (6, 10); a number of pairs of output terminals (7, 8), between each of which a respective electric actuator (3) is connected in use; and controlled switches (11, 12) for connecting the electric actuators (3) to the electric energy source (6, 10) independently of one another; the method including the step of controlling the controlled switches (11, 12) to supply an electric current to the electric actuators (3) via the electric energy source (6, 10).

Abstract: A method for regulating the current through an electromagnetic actuator. The actuator, a first switch and a current-measuring circuit form a series circuit. A free-wheeling diode is parallel-connected to the actuator. The first switch is closed and opened by a control and a pulse generator using a PWM signal (PWM=pulse width modulation) in such a way that the current flowing through the actuator and measured by the current-measuring circuit is regulated to a setpoint value (SW). The time duration of one on and off switching cycle of the PWM signal is altered, and a so-called dither function in the form of a low-frequency oscillation is superimposed on the PWM signal.

Abstract: A safety control circuit for a direct current electromotive nail driver comprises: a direct current power source for supplying power to the circuit; a control and protecting unit having a security switch, a trigger switch and a stop switch; and a motor for driving an object. When the security switch is turned on and then the trigger switch is pressed, the control and protecting unit will receive a signal from the trigger switch so as to conduct the motor and thus the motor operates to drive an object. When the motor operates through a predetermined time period, the stop switch will actuate a protection function of the control and protecting unit so that the motor cannot operate until the security switch is actuated again.

Abstract: Conventionally, a non-conductive period is provided in a region in the vicinity of zero of an AC power voltage via a voltage detection circuit 14 to turn off reliably. The FET 17 maintains the ON state within several switching cycles after the non-conductive interval to rapidly restore the magnetizing coil current, so that the magnetizing coil current rapidly increases. An object is to suppress beat noise in the electromagnetic device. Within a prescribed interval following the non-conductive interval, a partial voltage at a resistor 19 of an output V2 of a mono-stable circuit 20 is added as a bias voltage to a detection voltage of a magnetizing coil current at a resistor 18, and is detected by the IC 11. The IC 11 drives a FET 17 with a constant switching period after the non-conductive interval, thereby preventing the increase in the magnetizing coil current and resolving the problem.

Abstract: The present invention relates to a method for operation of an electro-magnet (2, 3) connected to an intrinsically safe direct current circuit which can be switched under control between two positions for the operation of the closing body of a hydraulic valve (5, 6), whereby using of an electronic control unit, the coil windings of the electro-magnet (2, 3) are taken in the pull-in phase of the armature of the electro-magnet to an exciting current and in the retaining phase of the armature to a lower retaining current as opposed to the excitating current, and a device with which the retaining current reduction is realized.

Abstract: A fuel injection control apparatus and fuel injection method are provided for injecting a suitable fuel with a quick response in accordance with variations in required fuel injection amounts, while improving the energy efficiency, and enabling support for an electromagnetic fuel injection apparatus. The control apparatus controls the electromagnetic fuel injection apparatus that pressurizes fuel to be injected, and has a driving circuit for driving a solenoid for fuel injection, a driving signal generating circuit for generating a solenoid driving signal based on an injection cycle signal for specifying a fuel injection period and a PWM cycle signal to provide to the driving circuit, and a control circuit for generating the PWM cycle signal with a duty ratio corresponding to a required fuel injection amount, and providing the PWM cycle signal and the injection cycle signal to the driving signal generating circuit.

Abstract: Electrostatic discharge can damage electronic equipment. It has been known to start a fire when it occurs when a motor vehicle's gasoline tank is being filled. A device for detecting, alarming, and/or neutralizing an electrostatic charge can help avoid these problems. A variable capacitor, the capacitance of which is made to vary periodically, is used to detect electrostatic charge. A first electrode of the capacitor is the object for which electrostatic charge is important. The capacitor's electrode is one by which the capacitance is varied. An amplitude of a signal from the electrode can be shown to be proportional to the electrostatic charge on the object.

Abstract: In order to provide as short a switching delay as possible in an undervoltage release which contains an electromagnet for tripping a switching device, and a driver circuit feeding the winding of the electromagnet, with the driver circuit being used to produce a pulsed holding current for the electromagnet, an electronic switch is fitted in the self-holding circuit that is produced via a freewheeling diode. This electronic switch can be driven as a function of the output signal from an undervoltage detector which is arranged within the driver circuit.

Abstract: A relay controller intermittently connects a power supply across a relay coil with a controlled duty cycle whenever the relay coil is to generate a magnetic field for opening or closing the relay's contacts. The duty cycle with which the controller connects the power supply across the coil controls limits a steady-state amplitude of current passing through the coil, thereby controlling the intensity of the magnetic field the coil generates.

Abstract: An electromagnetic, pulse width modulated control device includes a solenoid powered by a varying supply voltage and having an actuator movable from an extended position to a pulled in position by a first power level and into a hold in position by a second power level less than the first power level. A pulse width modulated circuit is connected with the solenoid and is responsive to the varying supply voltage for adjusting the pulse width accordingly so as to provide a substantially constant second power level applied to the solenoid to maintain the hold in position.

Abstract: An energy efficient multiple actuator control circuit is disclosed comprising a timing-slicing circuit for arranging and processing a pulsed select signal into a plurality of staggered pulse signals and a steering logic circuit for receiving the pulse signals and generating corresponding actuator enable signals. Latching solenoid actuators are arranged into position upon receipt of the pulsed actuator enable signals. The actuators maintain their position without any additional power. The circuitry is hardwired in that for a given select signal each actuator is activated into a predetermined position. The circuitry is scalable to arrange any plurality of actuators in any prearranged configuration, and the circuitry can perform properly over a broad variation of select signals.

Abstract: A method for starting up an electromagnetic actuator operating an engine cylinder valve. The actuator has two spaced electromagnets, between which an armature, connected to the cylinder valve, is reciprocated against a restoring spring from a center position to lie against a magnet pole face. An ECU alternatingly supplies the electromagnets with a capturing current, the level of which is regulated as a function of the approach of the armature toward a pole face, as detected by a sensor assembly. A reference temperature is detected for the magnets, and, at a normal temperature, the armature starts oscillating due to the alternating energization of the electromagnets, and is brought into contact with a pole face. Or, at a low temperature level, one of the electromagnets is supplied with a high current pulse.

Abstract: An outboard motor engine includes a plurality of cylinders. A fuel injector is disposed to inject a charge of fuel into an intake system. The fuel injector can form a portion of a direct injection system or a manifold injection system. The engine includes a processor that cycles each of the fuel injectors prior to energizing a fuel pump, a starter motor, or another electrical component of the outboard motor. By energizing the fuel injectors in sequence, a higher level of voltage can be applied to each fuel injector. In addition, by energizing the fuel injectors prior to energizing other electrical components, a higher level of voltage can be applied to each fuel injector.

Abstract: In the functional test process for a mechanical switching element, particularly a trigger in a high-voltage power switch, a coil core (2) is set in motion by the magnetic action of a current flowing through a coil (1). The electrical pulse is cut off as soon as the derivative of the measured current characteristic reaches a particular valve. This makes it possible to stop the movement of the core (2) and the plunger (4) without triggering the power switch.

Abstract: A method of controlling a proportional purge solenoid is provided to improve low flow resolution. The method includes looking-up a primary duty cycle corresponding to purge current in a three-dimensional surface by using purge flow and vacuum level as inputs. Should the primary duty cycle fall below a lowest allowable purge current threshold value, a secondary purge duty cycle (i.e., an on/off pattern of the primary duty cycle) is obtained from a two-dimensional table by using the actual calculated purge flow as an input. The two-dimensional table includes a sequence of program loops subdivided into a delay region wherein the purge flow and vacuum level data are learned, an updating region wherein the purge current of the three-dimensional surface is updated, and a control region wherein the primary duty cycle is toggled between on and off states. When the current program loop falls within the delay region, a recorded primary duty cycle is output.

Abstract: The present invention relates to a method and apparatus for control of current rise time during multiple fuel injection events. The invention utilizes a single boost voltage supply circuit, in which the boost capacitor is designed to store slightly more than twice the total energy required to pull-in a single fuel injector solenoid during the prescribed time. A reference waveform simulating the desired current rise time is compared to the actual boost voltage produced by the circuit. The boost voltage is modulated (switched on and off) in order to maintain the boost voltage within a predetermined window around the reference waveform. This modulation will compensate for any droop in boost voltage at the time of actuation, and will also compensate for two solenoids being actuated at the exact same time.

Abstract: A solenoid driving circuit contains solenoids, each of which is driven to produce a magnetic field for driving each of keys of a player piano. A NPN transistor is provided to allow or block a flow of current across each solenoid. The solenoid is connected between a DC power source for providing a source voltage and a collector of the NPN transistor whose emitter is grounded. A drive signal, which is subjected to pulse-width modulation, is supplied to a base of the NPN transistor, so that the NPN transistor is switched over between ON and OFF. A diode is introduced to provide prescribed forward voltage for attenuation of the current across the solenoid when the NPN transistor is turned OFF. Herein, an anode of the diode is connected to a connection between the solenoid and NPN transistor, while a cathode of the diode is connected to a cathode of a zener diode having prescribed reverse voltage. An anode of the zener diode is connected to the DC power source.

Abstract: A circuit for controlling current flow (I.sub.COIL) through a coil of an electromechanical device (101) uses a first timer (118) to measure the pulse width of a first drive pulse (22) and to store a proportional first value at an output (121). A second timer (124) receives the first value and generates a second value less than the first value to represent a time interval shorter than the pulse width of the first drive pulse. The second timer initiates the time interval with a second drive pulse (24) and provides a sampling signal (V.sub.SAMPLE) as the time interval terminates to sense an average current flow through the coil before the second drive pulse terminates.

Abstract: An exhaust gas recirculation valve control strategy comprised of learning and continuously updating system operating conditions that affect EGR valve control response, and controlling the EGR valve in response to the learned operating conditions for precise, robust EGR valve control. An adaptive base control signal is learned during an engine operating state where no EGR valve movement is needed, such as during engine idle. The base control signal is then continuously applied to the EGR valve, maintaining the valve at an energized level just below the beginning of valve opening. When a desired degree of opening is determined, the change in control signal is made in reference to the base control signal, reducing the magnitude of the resulting control signal change and control gains necessary to initiate valve movement, enabling faster and more stable EGR control.

Abstract: In a circuit configuration and a method for triggering at least one electrically triggerable magnet with a suitably targeted triggering power, the magnet switches a switching element into a desired switching position in which the switching element is retained. After the switchover of the switching element by the magnet into the desired switching position, the magnet is at least briefly repeatedly acted upon at predetermined time intervals with a triggering power corresponding to a desired switching position.

Abstract: A pulse width modulated drive circuit drives a solenoid operated valve in response to an input voltage signal from a control apparatus. The solenoid operated valve includes a coil that is energizable in response to energy received from the pulse width modulated drive circuit. The pulse width modulated drive circuit includes a pulse generator stage and an output stage. The pulse generator stage receives the input voltage signal from the control apparatus and a feedback signal from the coil which ultimately combine to form a control voltage in response to which the pulse generator stage generates a pulse width modulated signal whose duty cycle depends on the control voltage. The output stage receives the pulse width modulated signal from the pulse generator stage and generates in response thereto a pulse width modulated output signal across the coil. The pulse width modulated output signal has pulse width generally proportional to the control voltage and carries energy from a source of energy.