I have a project I am trying to put together. My understanding is lacking though. I would really appreciate some help in helping me to understand what I am missing!
The circuit would be a a logic level mosfet that would be controlled by a microcontroller. So 3.3v at the gate. It will be set in between the battery and the ignition wiring harness. Essentially, i would be breaking one wire in the harness. Which connect to the steering column, and inserting the mosfet/circuit. so when the car is started if the correct pin is entered, then the mosfet would complete the wiring harness circuit and allow the 12v to pass through.
To my understanding so far, I would need a logic level mosfet that has a low level rds(on) that is applied when the VGS is 3.3 or lower.
If the above were true, and all I had to do was apply a small 3.3v from the MCU and that would allow 12v to pass through the drain/source??
It seems to simple! I feel like there is more and like I am missing something. Could and would someone either point me in the right direction or help break this down, correct me, and or explain to give me a better understanding. I would very much appreciate it!
EDIT: I am just trying to get a better understanding of how these things work! If I apply the MCU's limited 3.3v to the gate, then that would allow 12v to pass from drain to source?? Do I need to accommodate for anything else? Anything like leakage voltage, kickback voltage, etc?