Using a MOSFET to toggle a 12v LED

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Hi All, I am working on a project where I am trying to control a 12v LED in an arcade button to toggle it on and off. From what I can tell I have wired it correctly but I am not getting the results I expect. In fact the LED never turns off it is always on.

On a breadboard I have basically wired this up:

1sYE0qn.png1064×680 34.5 KB
http://i.imgur.com/1sYE0qn.png

(I’m not sure if the diode is actually in the right direction on the diagram, but you get the idea)

I have a 10k resistor between the gate and source and one of [these guys at the drain. I’m using [this MOSFET to do the toggling.

It’s my understanding that if I do not have the +3.5v coming into the gate the LED should not light, however it is always on. I feel like I’m missing something but I don’t know what it is.

Thanks!](N-Channel MOSFET 60V 30A - COM-10213 - SparkFun Electronics)](https://gameroomsolutions.com/shop/chrome-illuminated-led-arcade-push-button/)

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The diagram doesn’t make much sense. Why is V2 connected to ground on one end, and to nothing on the other?

To switch on the MOSFET, you need to apply at least +3-5 V to the gate. Make a pencil drawing of the setup and post a picture.

You don’t need a MOSFET if you have a switch, and in any case the circuit is not capable of “toggling” the LED.

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So basically I’m trying to replicate this

http://bildr.org/blog/wp-content/upload … htbulb.png

I thought I had it, here is a pencil drawing of what I have connected:

AU7hWkZ.jpg800×600 38.4 KB
http://i.imgur.com/AU7hWkZ.jpg?5

4

If you have the pinout of the MOSFET correctly connected and drawn, that should work.

Have you connected all the grounds together?

5

So it was user error. I have this [DC barrel jack to attach the 12v supply to the breadboard. I had plus and minus backwards. Once I sorted that out it worked. Thanks!](DC Barrel Jack Adapter - Breadboard Compatible - PRT-10811 - SparkFun Electronics)