Touch Potentiometer Hookup Guide
Joel_E_B Introduction
The Touch Potentiometer, or Touch Pot for short, is an intelligent, linear capacitive touch sensor that implements potentiometer functionality with 256 positions. It can operate as a peripheral to a computer, embedded microcontroller or in a stand-alone capacity. The Touch Potentiometer provides both a dual-channel analog and PWM output for direct control of other circuitry. Configurable analog and PWM transfer functions support a wide variety of applications.
Recommended Materials
This tutorial will go over numerous examples of how to us the Touch Potentiometer. The materials needed to follow along with each example will be listed at the beginning of that example's section.
Suggested Reading/Viewing
First and foremost, Dan Julio of danjuliodesigns has written an amazing user manual for the Touch Potentiometer. Most of the information you need to know about the Touch Pot can be found in that document including maximum power ratings, dimensional drawing, and very detailed operational instructions. You can download the manual via the link below or you can always grab the most up-to-date version from his website.
To better understand the Touch Potentiometer and how it functions, it will help to have a good understanding of the following concepts. If there's any you are unfamiliar with, visit the corresponding tutorial first, then head on back.
- Resistors - The section on potentiometers is of particular interest.
- Serial Communication - The Touch Pot uses Serial Communication to talk to the utility used to configure the board.
- I2C - The Touch Pot uses I2C Communication to communicate with embedded microcontrollers or with other Touch Pots on the bus.
- Pulse-width Modulation - The Touch Pot has a PWM output for interfacing with lighting systems or other controllers that accept PWM inputs.
- Hexadecimal and Binary are used a lot when diving in to the operation of the Touch pot.
- The Touch Pot relies on Capacitive Sensing to detect changes to its current setting. Check out the video below for a detailed breakdown of how Cap Sensing works and different methods of detecting cap sense.