TIDUE90
July 2018
Description
Resources
Features
Applications
Design Images
1
System Description
1.1
Key System Specifications
2
System Overview
2.1
Block Diagram
2.2
Design Considerations
2.2.1
Classification of Scenarios With Liquid Present
2.2.2
Liquid Influence on Capacitive Touch Sensing
2.2.3
Self Capacitance and Mutual Capacitance
2.2.3.1
Self Capacitance
2.2.3.2
Mutual Capacitance
2.2.4
Other Considerations
2.3
Highlighted Products
2.3.1
MSP430FR2633
2.4
System Design Theory
2.4.1
Shield Sensor Electrodes
2.4.2
Mutual Capacitance Shielding
2.4.3
Design for Noise Immunity
2.4.4
Power Supply Grounding Effect
3
Hardware, Software, Test Requirements, and Test Results
3.1
Required Hardware and Software
3.1.1
Hardware
3.1.2
Software
3.2
Test and Results
3.2.1
Liquid Test With Well Grounded Power Supply
3.2.1.1
Continuous Water Flow Test
3.2.1.2
Continuous Water Spray Test
3.2.2
Conductive Noise Immunity Test
3.2.3
Liquid Test With Battery-Powered Supply
3.2.3.1
Continuous Water Flow Test
3.2.3.2
Continuous Water Spray Test
3.2.4
Third Party Test Report
4
Design Files
4.1
Schematics
4.2
Bill of Materials
4.3
PCB Layout Recommendations
4.3.1
Layout Prints
4.4
Altium Project
4.5
Gerber Files
4.6
Assembly Drawings
5
Software Files
6
Related Documentation
6.1
Trademarks
7
About the Author
6
Related Documentation
CapTIvate™ Technology Guide
Enabling Noise Tolerant Capacitive Touch HMIs With MSP CapTIvate™ Technology