A drive circuit for controlling a solenoid valve having a solenoid coil and a poppet that translates therein is provided. The drive circuit includes a first node, a second node, a control circuit, and a flyback circuit. The first node is configured to be energized by a power source to a first voltage. The control circuit is coupled to the first and second nodes, and is configured to: (1) selectively couple the first and second nodes in series with the solenoid coil, and periodically energize the solenoid coil using a pulse-width-modulated (PWM) signal having a frequency and a duty cycle configured to regulate a current conducted through the solenoid coil. The flyback circuit is coupled to the solenoid coil and configured to energize the second node to a second voltage with energy stored in the solenoid coil.

A solenoid control circuit can make measurements during operation to determine the state of a solenoid and can provide for rapid re-energization of a solenoid upon detection of a dropout condition. A method of controlling a solenoid can include closing an input switch, cycling a low side switch based on voltage drop across a resistor, opening the input switch after a time interval, closing the low side switch and driving a discharge switch to control the discharge current rate from an energy storage device to an inductor. The method can include determining a condition of the inductor based on a time interval between actuation of comparators and maintaining a level of energy in the energy storage device sufficient to cause the inductor to produce a magnetic field for actuating a valve.

A method of controlling a solenoid valve having a solenoid coil and a poppet includes energizing a first node to a first voltage, and coupling the first node to the solenoid coil and energizing the solenoid coil using a pulse-width-modulated (PWM) signal having a frequency and a duty cycle configured to regulate a current conducted through the solenoid coil to below an opening threshold. The method further includes energizing a second node to a second voltage with energy stored in the solenoid coil, and coupling the second node to the solenoid coil and energizing the solenoid coil using a DC signal configured to increase the current to above the opening threshold. The method further includes coupling the first node to the solenoid coil and energizing the solenoid coil using the PWM signal having a frequency and duty cycle configured to regulate the current to above a closing threshold.

A drive circuit for operating a solenoid includes a main switch and a charge pump circuit. The main switch is coupled in series with a coil of the solenoid. The main switch is configured to selectively enable current flow from a voltage source according to a main switching signal to translate a poppet of the solenoid between an opened position and a closed position. The charge pump circuit is coupled to the voltage source. The charge pump circuit is configured to discharge through the coil to translate the poppet from the closed position to the opened position, and to charge when the poppet is held in the opened position.

A solenoid control circuit can make measurements during operation to determine the state of a solenoid and can provide for rapid re-energization of a solenoid upon detection of a dropout condition. A method of controlling a solenoid can include closing an input switch, cycling a low side switch based on voltage drop across a resistor, opening the input switch after a time interval, closing the low side switch and driving a discharge switch to control the discharge current rate from an energy storage device to an inductor. The method can include determining a condition of the inductor based on a time interval between actuation of comparators and maintaining a level of energy in the energy storage device sufficient to cause the inductor to produce a magnetic field for actuating a valve.

Provided is a fuel control device for an internal combustion engine that is able to detect the correct boost voltage regardless of the temperature condition, and stabilize the boost voltage value, and is able to inject an accurate amount of fuel from a fuel injection valve. The boost voltage value detected when current is not flowing in a boosting capacitor at least during a boosting operation is taken as a legitimate boost voltage value, and this legitimate boost voltage value is compared with a prescribed boost voltage value to control the boosting operation. Thus, it is possible to stabilize the boost voltage at a legitimate boost voltage value regardless of the temperature condition, and it is possible to inject an accurate amount of fuel from a fuel injection valve, thereby improving fuel consumption.

An electronic circuit configured to control an electromagnetic actuator with an electric coil, comprising at least one first electronic switching element, a capacitor, and a diode connected to the first electronic switching element, the capacitor, and the electrical coil to form a step-up converter, wherein the capacitor is configured to be charged to a voltage that is greater than an operating voltage of the electronic circuit.

A drive circuit for controlling a solenoid valve having a solenoid coil and a poppet that translates therein is provided. The drive circuit includes a supply bus, a return bus, a flyback circuit, and a switch. The supply bus is configured to couple the solenoid coil to a power supply and supply a coil current. The return bus is configured to provide a ground path for the coil current. The flyback circuit is coupled in parallel to only the solenoid coil. The flyback circuit includes only a bipolar diode. The switch is coupled in series with the solenoid coil and configured to couple and decouple the solenoid coil to the return bus.

A power converter module is connected to an electrical power supply and is configured to generate a first voltage and a second voltage for controlling operation of a valve, where the valve includes a solenoid for affecting opening and closing of the valve. The first voltage is a boost voltage for accelerating opening of the valve. The second voltage is a holding voltage for maintaining the valve in an open state. A boost control module is configured to control supply of the first voltage to the solenoid of the valve in accordance with a first state of an opening boost control signal when a valve control signal directs opening of the valve, and is configured to control supply of the second voltage to the solenoid of the valve in accordance with a second state of the opening boost control signal when the valve control signal directs opening of the valve.

A circuit for driving an inductive load may include an input, an output, a first switch, and at least one capacitor. The first switch may cause the capacitor to be charged by the supply voltage via the inductive load. A device may discontinue the charging of the capacitor when the voltage has reached a predetermined level greater than that of the supply voltage. A first and a second diode may prevent the capacitor from discharging via the first switch and blocking inductive load current from entering the power supply, respectively. A second switch and the capacitor may be connected to the third switch to cause discharging of the capacitor via the third switch into the inductive load. Closing of the first switch may cause a current sufficient for actuating a mechanical valve to be induced in the inductive load.