5-12V Capacitive Touch Switch

Capacitive Touch Switch for direct control of LED stripes or a relais

Similar projects worth following
I built another LED lamp and wanted to use a TTP223 capacitive switch as usual. But Led Stripes have 12V and there was my problem again, the available TTP223 boards are 3-5V and have only a small switching current. Besides, I don’t need the LED on the board. So I've build my own

A 5-12V  Capacitive Touch Switch based on a TTP223

I think the video explains it all :)

Where I have installed it

  • 1 × TTP223 SOT23-6 Chip Capacitive Switch circuit
  • 1 × Q1 FMMT617-625 SOT23 Transistor or equivalent 3A NPN Transistor
  • 1 × D1 1N4148W SOT123 (optional)
  • 1 × BZX BZX84 4.7V or 5.1V SOT23
  • 1 × R1 Resistor 2k2 1206

View all 8 components

  • 1
    The Prototype

    So I built a prototype with what I had lying around.

    • 1 TTP223
    • 1 Zener Dioder 5.1V
    • 1 2k2 Resistor
    • 1 1k5 Resistor
    • 1 BD137 Transistor

    Panelized Design 6 x 12V TTP223 Touch Controller

  • 2
    PCB Design

    First the schematic. I also included a flyback diode in the design, so you can also directly control a relay. The TTP223 chip has the same components as on the small original board. As on that, the 22pf capacitor is optional and is used to control the sensitivity of the touch controller. An FMMT617-625 comes into play as the transitor. You can also use another one. However, according to the data sheet, this one delivers 18V 3A. But I won’t go over 2.5A, just to be on the safe side :)

    Panelized Design 6 x 12V TTP223 Touch Controller

  • 3
    Part List
    • 1 TTP223 SOT23-6 Chip
    • Q1 FMMT617-625 SOT23 Transistor or equivalent
    • D1 1N4148W SOT123 (optional)
    • BZX BZX84 4.7V or 5.1V SOT23
    • R1 Resistor 2k2 1206
    • R2 Resistor 1k5 1206
    • C1 Capacitor 100nF 1206
    • C2 Capacitor 22pF 1206 (optional)

View all 10 instructions

Enjoy this project?



Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates