@psoc73: thank you for the info but we already had all those ANs as well as a psoc3 working design that reads 2 5 x 12 matrix membrane keyboards, 2 encoders and communicates with a PC through a USB port. We were looking specifically for large capacitive keyboards design experience because ours is limited to 6-sensor pannels and are close to the project deadline.
Thank you too. I already had the AN (without the Obsolete stamping). What it made me wonder about the design featured in the reference AN is that no new AN along that line has been made available, not even with the new psoc families or the improved capacitive sensing techniques. Do you know if it was tested out of the lab and what the experience and user feedback was? Would you say that such layout (slightly modified to suit our keyboard layout) would work alright with a psoc3? Anyways, it would be great if you can get us the original project.
Again thank you to all those that replied.