Transistor / MOSFET tutorial
Why Electrical Engineering Stack Exchange recommends it
Electronics Stack Exchange answerers point people to it as a quick, beginner-friendly explanation of using a transistor or MOSFET as a switch when driving motors, lasers and other loads from logic pins.
Recommended by 3 people across 3 different months, 2011 to 2021.
What it is
A short beginner tutorial from Afrotechmods showing how to use an N-channel MOSFET as a switch to turn loads like motors or lights on and off from a low-power signal. It includes the tip of adding a 100k pull-down resistor between gate and ground, and demonstrates a diode across a motor.
What people said
Recommends John · 2011-08 · Electrical Engineering Stack Exchange · on “Circuit design questions related to powering laser from Arduino UNO”
Check out this video [this video] . MOSFETS tend to be easier for beginners to understand than BJTs. Read the documentation on the laser to determine what its electrical characteristics are. Good luck spying, as I assume that is what this is for ;-)
Recommends AndrejaKo · 2011-11 · Electrical Engineering Stack Exchange · on “Using RS232 to light bulb or move motor”
The answer is simple: You need a transistor connected to RS-232 port. Then using transistor, you can control a relay or whatever you want. For transistors, there's a simple tutorial here [this video] that I like. I recommend that at first you use an IC like MAX232 to provide a 0 V to 5 V at the output. While it is possible to connect a transistor directly to serial port, that could be problematic due to wide range of possible output voltages on the port. There's a nice tutorial for setting up a MAX232 circuit here [LINK] . There's actually one more thing I should mention in my example: Since FETs are supposed not to consume current, you may need to use a pull-down resistor on the output of the MA
Recommends abdullah kahraman · 2011-12 · Electrical Engineering Stack Exchange · on “how to construct stepper motor driver?”
Controlling higher currents and voltages with the digital output is done using switches. Stepper motor driving is basically the same. It may change depending on your drive technique and stepper motor type, however it will be just your digital output to electronic switches that controls the windings. Go to here [LINK] and scroll down to "Using a transistor as a switch" to learn more about this. Also, this video [this video] is a great tutorial. Don't forget the flyback (kickback, freewheeling) diode. Here [LINK] is a video about that. Also it is important to know your stepper motor type. Driving techniques differ by stepper motor and winding type, however the electronic switch theory remains the s
Cites Dat · 2021-07 · Electrical Engineering Stack Exchange · on “What is the purpose of a diode connected to the pins of a motor?”
I am new to electronics. I am watching this video. [this video] At 4:03, you can see a diode that connects the two pins of the motor: [LINK] What role does the diode play?