NXP LPC11xx Capacitive Touch Sensing Application Note

About this manual

This document explains how to implement a simple capacitive touch sensing function using the Analog-to-Digital Converter (ADC) input of the NXP LPC11xx microcontroller. It details the working mode of the system, which involves charging an external capacitor via an IO pin configured as an output, followed by discharging it while configured as an ADC input to detect changes in capacitance caused by a finger touch. The process includes configuring the pin, starting the ADC conversion, sampling the result, and debouncing the signal.

What's inside

• Introduction
• Working Mode
• Demo Program
• Source Code
• References

Frequently asked questions

What hardware is used for the demonstration in this note?

The demonstration uses the PCF8883 evaluation kit with a MicroCore48 board.

Which microcontroller series is covered?

The application note covers the LPC11xx series microcontrollers.

What compiler and environment are used for the example code?

The code is written in C and compiled using KEIL uVision (MDK-ARM V4.14).