Hi,
I would like to hear suggestions on a simple solution how to implement proximity/hand over detection in a keyboard I'm designing.
I have a steel plate under keycaps, so I was thinking about capacitive detection, but I don't know how well it would work in real world situation...
Idea is to use it to turn on/off backlight, I know this could easily made by detecting key press, but I want a bit more sophisticated solution, even if it will add few bucks to the BOM.
All suggestions are welcome.
EDIT:
This is what I'm looking for:
Find on Google:
"When something approaches, such as a steel disk or a hand, the impedance changes. When the impedance passes a certain threshold, the controller will know to turn on/off the backlight" (green PCB – "Santiago proximity detector"):
