只使用一个ADC电容式触摸（CVD）

This application note describes a new hardware
sensing method called Capacitive Voltage Divider
(CVD) which uses no external components. It requires
only the ADC to perform capacitive touch sensing. The
principle is simple, and can be applied to nearly any
Microchip PIC
®
device with an ADC.
AN1298
Capacitive Touch Using Only an ADC (“CVD”)
Sensing Steps
Authors: Thomas Perme
Dieter Peter To perform the sensing, do the following:
Microchip Technology Inc. 1. Drive secondary channel to VDD as digital
output.
INTRODUCTION 2. Point ADC to the secondary VDD pin (charges
CHOLD to VDD).
This application note describes a new hardware