Today, I messed around with a little electronic component called the 2N7000 MOSFET. It’s a tiny guy, but pretty useful for switching things on and off in circuits. I’ve been wanting to get more hands-on with these things, so I thought I’d document the whole process.

First off, I grabbed a 2N7000 from my parts bin. Then I pulled up its datasheet. It’s always a good idea to see what the manufacturer says about how to use it. I looked the pinout to figure out which leg is which – you’ve got the Source, Gate, and Drain.
Next, I set up a simple circuit on my breadboard. I basically wanted to use the 2N7000 to control an LED, using my Arduino to trigger it. I connected the Source pin to ground, the Drain pin to the negative side of the LED, and the positive side of the LED to a resistor, and then to the power supply. To control the MOSFET, I connected the Gate pin to a digital pin on my Arduino through another resistor.
- First experiment: I wrote a simple Arduino sketch to send a HIGH signal to the Gate pin. I loaded it up, powered it on, and boom! The LED lit up.
- Second experiment: I modified the code to send a LOW signal to the Gate. As expected, the LED turned off. This means I’m successfully using the Arduino’s digital output to control the flow of current through the LED using the MOSFET as a switch.
After that, I decided to play around a bit more. I changed the code to make the LED blink. That worked like a charm. It’s pretty satisfying to see your code physically doing something in the real world. I tried different blinking speeds, and the 2N7000 handled it all without a hitch. It did get a tiny bit warm after running for a while, but nothing to worry about.
A Few Things I Learned
- This 2N7000 is controlled by voltage at the Gate. When I raise the voltage on the Gate pin, it allows current to flow from the Drain to the Source.
- To turn it off, I just ground the Gate pin. It’s that simple.
- These MOSFETs are pretty handy for switching stuff on and off, especially if you want to control something that uses a different voltage than your microcontroller.
Overall, it was a successful day of tinkering. I got my hands dirty, learned a bunch about how these 2N7000 MOSFETs work, and even got a little LED to dance to my tune. I can definitely see myself using these in future projects. Maybe I’ll try driving a small motor next. Stay tuned!