Skip to main content

TOUCH SWITCH CIRCUIT WITH MOSFET


TOUCH SWITCH CIRCUIT WITH MOSFET


1,326
13


About: Electronic Hobby Store 

Intro: Touch Switch Circuit With MOSFET

Created by: Jonsen Li
Overview:
The simple touch switch LED circuit utilizes biasing characteristics of the MOSFET.
MOSFET stands for Metal-oxide-semiconductor field effect transistors. It is a voltage controlled device meaning that the current passing through the device is controlled by the voltage between two terminals.
Parts you will need:
A power MOSFET (IRFZ-44 NPN) (Lee's ID: 71211)
9V battery (Lee's ID: 83741)
12V LED bulb (Lee's ID: 5504)
Jumper wires (Lee's ID: 21802)
Breadboard (Lee's ID: 10686)
9V battery clip (Lee's ID: 653)

Step 1: A Quick Tip to Keep in Mind

Since the mosfet is a voltage controlled device, it is very sensitive to electrostatic discharges and may be damaged due to the static charges flowing through the terminals.

Step 2: Hooking Up Wires to the MOSFET

Picture of Hooking Up Wires to the MOSFET
Simply connect the jumper terminals to the legs of the MOSFET
For IRFZ-44:
The left leg is the gate terminal (white jumper)
The middle is the drain terminal (brown jumper)
The right leg is the source terminal (grey jumper)

Step 3: Fully Assembled Circuit

Picture of Fully Assembled Circuit
Picture of Fully Assembled Circuit
To turn the LED on, simply touch the drain terminal and gate terminal at the SAME time.
To turn the LED off, touch the source terminal and gate terminal at the SAME time
The logic behind this project is the characteristics of the MOSFET:
For the LED to light up, the MOSFET must fully ON, which means Vds > Vgs – Vt. Since MOSFETs are voltage-controlled transistors, touching the drain and gate terminal at the same time will “short” them, therefore allowing the MOSFET to be fully ON.
On the other hand, touching the gate and source terminal will turn the MOSFET fully OFF, because it cannot satisfy the overdrive voltage (Vov) requirement (Vov = Vgs – Vt, Vgs = 0V).
If you have difficulties turning the circuit on and off, wetting your hands may help.

Step 4: A Video Demonstration


Here is a quick video demonstration of the touch switch in action.Here is a quick video demonstration of the touch switch in action.

Comments

Popular posts from this blog

Arduino NANO 3X3X3 LED CUBE

DIY | 3X3X3 LED CUBE FOR ARDUINO NANO+ By   RGBFreak   in   Technology Arduino 17,143 146 22 Featured Download Favorite By   RGBFreak RGBFreak's YouTube Channel Follow More by the author: About: Hi there visitor! First of all thank you for checking out my profile! My name is Youri. I study Technical Computer Science in the Netherlands. I especially love the electronical part of my study. Since I l...   More About RGBFreak » Intro: DIY | 3x3x3 LED Cube for Arduino Nano+ Hi everyone! My name is RGBFreak and I created a YouTube channel quite recently. I love DIY and I especially love LED's, so that's why I decided to make my own 3x3x3 LED Cube! You will need the following items to make this LED Cube: • 27 single colored LED's. • Arduino Nano or one of his bigger brothers. • 3 NPN Transistors. I used the BC547. • 3 pin headers with 3 pins. • 1 pin header with 4 pins. • A piece of perfboard. • A few small cables. Ad

DIGITAL UV-METER, WITH OLED DISPLAY. ARDUINO PROJECT FOR BEGINNERS

DIGITAL UV-METER, WITH OLED DISPLAY. ARDUINO PROJECT FOR BEGINNERS By   techn0man1ac   in   Technology Arduino 4,792 87 13 Featured Download Favorite By   techn0man1ac Techn0man1ac blog Follow About: Techn0man1ac - техноманьяк   More About techn0man1ac » Intro: Digital UV-meter, With OLED Display. Arduino Project for Beginners Video demonstration (English subtitles). Hello,   instructable . Today I will tell you how to make a simple digital VU meter (sound level meter) using Arduino and OLED displays and 2 resistors by yourself (DIY). The device is quite simple, for beginners it will be a rewarding experience. Add Tip Ask Question Comment Download Step 1: Components for This Arduino Project: 3 More Images Arduino Nano V3.0; 0.96 inch IIC I2C 128X64 OLED Display; One 10K, resistor(R1 no scheme); One 10K-100K potentiometer(R2no scheme); Wires. Add Tip Ask Question Comment Download Step 2: Dev

Ultrasonic Distance Sensor in Arduino With Tinkercad

  Ultrasonic Distance Sensor in Arduino With Tinkercad Let's measure distances with an ultrasonic rangefinder (distance sensor) and Arduino's digital input. We'll connect up a circuit using a breadboard and use some simple Arduino code to control a single LED. You may have already learned to   read a pushbutton   and   PIR motion sensor   with Arduino's digital input, and we'll build on those skills in this lesson. Ultrasonic rangefinders use sound waves to bounce off objects in front of them, much like bats using echolocation to sense their environment. The proximity sensor sends out a signal and measures how long it takes to return. The Arduino program receives this information and calculates the distance between the sensor and object. Find this circuit on Tinkercad Explore the sample circuit embedded here by starting the simulation and clicking on the proximity sensor. This will activate a highlighted area in front of the sensor with a circle "