SparkFun Touch Potentiometer

The SparkFun Touch Potentiometer, also known as Touch Pot, is a smart linear capacitive touch sensor that performs potentiometer functions with 256 positions. It can function as a computer or embedded microcontroller peripheral or independently. The Touch Pot offers a dual-channel analog and PWM output for direct control of other circuits. The configurable analog and PWM transfer functions support a wide range of applications, from volume control to LED dimming.

The Touch Potentiometer is managed by a Microchip PIC16F1829 8-bit micro-controller that offers the host interface, LED control, capacitive sense, and peripheral control functions. It features a built-in low-dropout voltage regulator that allows operation over a range of input voltages up to 12V. It also comes with breadboard-friendly connectors for easy use. The Touch Pot communicates with a utility app created by our collaborator, Dan Julio, over a serial connection. This app allows you to change configuration settings, alter LED behavior, calibrate the capacitive touch sensor, view current readings in jabber mode, and much more.

Note: The product is a collaboration with danjuliodesigns. A portion of each sale goes back to them for product support and continued development.

Features:

• Logic-level serial and I2CTM dual host interfaces
• Dual 8-bit 20 k-ohm 3-terminal digitally controlled variable resistor outputs
• PWM output
• 8 LED display with different display modes and intensity levels
• Interpolated (soft) changes between touches option
• Configurable touch sensor parameters for various PCB covers
• Configurable I2C address for multiple devices on one bus
• Configurable linear or non-linear PWM transfer function
• Configurable linear or simulated logarithmic variable resistor transfer function
• Variable resistor supports single- or dual-supply operation
• Simple register interface with jabber option
• Programmable power-on default operation
• Built-in calibration procedure
• User-accessible EEPROM data storage
• Built-in 5V LDO voltage regulator
• Through-hole and SMT connectors

Documents:

• Schematic
• Eagle Files
• User Manual
• Hookup Guide
• Datasheet (AD5262BRU)
• Touch Pot Utility Application
• Source Code
• GitHub (Design Files)
• Product Page
• Product Video