Team,
My customer has a question concerning the thickness between a sensor and its associated shield when using the FDC1004.
From Application Report SNOA928A, Capacitive Proximity Sensing Using the FDC1004, Page 6:
The size of the shield and distance to the sensor electrode significantly affects the sensing range. A shield
that is larger than and closer to the sensor electrode reduces the sensitivity and maximum range, but it
limits the amount of interference seen by the sensor electrode. A smaller shield further away from the
sensor electrode has an opposite effect on sensitivity and detection range. For more information on
shielding effects, refer to the Capacitive Sensing: Ins and Outs of Active Shielding application note.
What is the tradeoff for the shield to sensor distance versus sensing range? While most of the application notes reference FR4 at a thickness of approximately 60 mils, Application Report SNOA926A uses Plexiglas at a thickness of approximately 23.6 mils. I’m primarily interested in thicknesses less than Plexiglas.?
Thank you for your help
