I am using CapSense on a circular board and my aim is to enable wake-on approach from as far away as possible. I have done a first design but I am not totally satisfied yet with the result. Would be great if I could get some additional tips on how to make my design better.
Here is what I have done:
- the board is circular, 133mm in diameter (~5.2 inches) and has 4 layers
- I put the circular sensing electrode (1.6mm/63mil width) on the circumference of the top layer (nothing else on the other layers)
- the driven shield electrode is placed right behind it (1mm/40mil width with 1mm/40mil space to the sensing electrode, circular and on top and bottom layer)
- the rest of the circuitboard (all the components plus guard ring) with 1mm/40mil space behind the shield electrode.
I studied the available pdfs from Cypress and also the schematic and layout of the MBR3 eval kit. Is there something I could do better layout wise to get a longer proximity sensing distance?
Thanks a lot for your help!
Could you please create the tech support case in cypress.com website and share the layout and schematic file, and project so it will help us to analyze the schematic and layout completely. To create tech support case, please go to cypress.com-> Design support-> create a support case.