Methods and drive circuit for controlling a solenoid valve

A drive circuit for controlling a solenoid valve having a solenoid coil and a poppet configured to translate therein, said drive circuit comprising:

• a first node configured to be energized to a first voltage using a power source;
• a flyback circuit coupled to the solenoid coil;
• a second node configured to be energized to a second voltage using energy stored in the solenoid coil using the flyback circuit;
• a control circuit coupled to said first node and said second node, said control circuit configured to:
• couple the first node to the solenoid coil and energize the solenoid coil using a pulse-width-modulated (PWM) signal having a first frequency and duty cycle configured to regulate a current conducted through the solenoid coil to below an opening threshold to maintain the poppet in a closed position;
• couple the second node to the solenoid coil and energize the solenoid coil using a DC signal configured to increase the current to above the opening threshold to translate the poppet toward an opened position;
• and
• couple the first node to the solenoid coil and energize the solenoid coil using the PWM signal having a second frequency and duty cycle configured to regulate the current to above a closing threshold to maintain the poppet in the opened position.