How can voltage be seen through a mosfet? I have a backplane board with the following circuit, the mosfet is pulsed by the main circuit board operating the electromagnetic counters. The counters are not needed anymore and need to be eliminated. When they are removed I get an error message saying they are missing. So the main board is sensing their presence. I need to fool the board into thinking they are there.
View attachment f7341 Datasheet.pdf
My theory is that 12V is sitting at the "static" mosfet when the electromagnetic coil is present. This is creating a high state on the gate across the silicon dioxide (like a capacitor) which is sensed by the board. Once the board has determined the presence of the counter coil, it pulses "with a higher voltage"the mosfet to activate the counter.
My solution (I am guessing here) is to remove the coil and mosfet and istall a capacitor and a diode to simulate the coil being present, as follows.
Please somebody tell me if this even close or if I am way off!
View attachment f7341 Datasheet.pdf
My theory is that 12V is sitting at the "static" mosfet when the electromagnetic coil is present. This is creating a high state on the gate across the silicon dioxide (like a capacitor) which is sensed by the board. Once the board has determined the presence of the counter coil, it pulses "with a higher voltage"the mosfet to activate the counter.
My solution (I am guessing here) is to remove the coil and mosfet and istall a capacitor and a diode to simulate the coil being present, as follows.
Please somebody tell me if this even close or if I am way off!