Hey,
Description:
Im designing a digital circuit which controls a latching solenoid. I have attached the final section of the circuit (sorry for the hand drawing). There is a signal coming from the control box, such that a "1" means the solenoid should be latched and a "0" means the solenoid should be unlatched. The way this works is the relay is energized when the MOSFET is turned on, which then pulses the supply to the solenoid and makes it latch. (Pulse again to make it unlatch).
I have used and XOR gate to xor the control signal with the feedback. Feedback is needed so not to unlatch the solenoid when it should be latched.. and vice versa.
The XOR gate is CMOS with Vdd=12V, the control signal is 12V high, and 0V low.
The solenoid/relay/MOSFET has a separate supply to the XOR/Control circuit, but their grounds/commons are linked(i.e. the same point).
This circuit works correctly when tested without feedback.
Question:
I have indicated where i tried to take the feedback from, but it does not work.. it forces the solenoid to oscillate between latched/unlatched states. Where can i take the feedback from? or what extra circuitry is needed?
Thanks in advance
Description:
Im designing a digital circuit which controls a latching solenoid. I have attached the final section of the circuit (sorry for the hand drawing). There is a signal coming from the control box, such that a "1" means the solenoid should be latched and a "0" means the solenoid should be unlatched. The way this works is the relay is energized when the MOSFET is turned on, which then pulses the supply to the solenoid and makes it latch. (Pulse again to make it unlatch).
I have used and XOR gate to xor the control signal with the feedback. Feedback is needed so not to unlatch the solenoid when it should be latched.. and vice versa.
The XOR gate is CMOS with Vdd=12V, the control signal is 12V high, and 0V low.
The solenoid/relay/MOSFET has a separate supply to the XOR/Control circuit, but their grounds/commons are linked(i.e. the same point).
This circuit works correctly when tested without feedback.
Question:
I have indicated where i tried to take the feedback from, but it does not work.. it forces the solenoid to oscillate between latched/unlatched states. Where can i take the feedback from? or what extra circuitry is needed?
Thanks in advance
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