Introduction:
In this project of we “interfaced TTP223 Capacitive Touch Sensor Switch with Arduino” for designing a touch detector. It is a simple project for switching circuits with the help of simple touch. Any home appliances can be controlled with the touch sensor by interfacing relay with it.
Check the advance version of this project: Touch Based Door Lock System Using Arduino & Touch Sensor TTP223
The application areas of this project are Waterproofed electric products, Button key replacement, Consumer products, etc. We need Switch to control electronics appliances. Some time electrical switches will give a shock when we use electrical switches with wet hands. An electronic load is much interactive than ordinary switches, maybe some projects need a touch switch. Here the Digital Capacitive touch sensor Arduino interface is made as an experiment.
TTP223 CAPACITIVE TOUCH SENSOR
Introduction:
A capacitive touch sensor module based on the dedicated TTP223 touch sensor IC. The module provides a single integrated touch sensing area of 11 x 10.5mm with a sensor range of ~5mm. An on-board LED will give a visual indication of when the sensor is triggered. When triggered the module’s output will switch from its idle low state to high (default operation). Solder jumpers allow for reconfiguring its mode of operation to be either active low or toggle output.
Check the TTP223 Datasheet
Internal Structure:
TTP223 is 1 Key Touchpad detector IC, and it is suitable to detect capacitive element variations. It consumes very low power and the operating voltage is only between 2.0V~5.5V. The response time max about 60mS at fast mode, 220mS at low power mode @VDD=3V. Sensitivity can adjust by the capacitance(0~50pF) outside.
Working Mechanism of TTP223 Capacitive Touch Sensor
Capacitive screens do not use the pressure of your finger to create a change in the flow of electricity. Instead, they work with anything that holds an electrical charge – including human skin.
When a finger hits the screen a tiny electrical charge is transferred to the finger to complete the circuit, creating a voltage drop on that point of the screen. The software processes the location of this voltage drop and orders the ensuing action.
Touch Detector using Arduino TTP223 Capacitive Touch Sensor Switch
Components Required:
- Arduino Uno Board
- TTP223 Capacitive Touch Sensor
- LED or Buzzer
- Breadboard
- Connecting Wires
Connections:
Do the connection as follows:
Sig Pin of TTP223 Capacitive Touch Sensor ——————- Arduino Digital Pin D7
Vcc Pin of TTP223 Capacitive Touch Sensor ——————- Arduino 5V
GND Pin of TTP223 Capacitive Touch Sensor ——————- Arduino GND
LED positive pin —————————————– Arduino Digital Pin D13
LED negative pin —————————————– Arduino Ground Pin
Circuit Diagram:
Arduino Source Code:
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#define ctsPin 7 // Pin for capactitive touch sensor int ledPin = 13; // pin for the LED void setup() { Serial.begin(9600); pinMode(ledPin, OUTPUT); pinMode(ctsPin, INPUT); } void loop() { int ctsValue = digitalRead(ctsPin); if (ctsValue == HIGH){ digitalWrite(ledPin, HIGH); Serial.println("TOUCHED"); } else{ digitalWrite(ledPin,LOW); Serial.println("not touched"); } delay(500); } |
Video Preview & Explanation:
