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General => General Chat => Topic started by: rcourtney on September 06, 2015, 09:41:33 pm

Title: Using projective capacitive sensing with common keypads
Post by: rcourtney on September 06, 2015, 09:41:33 pm
I am looking at an attractive case for a protected outdoor keypad.  I don't want to use contact keypad sensing due to environment
deterioration of the carbon button spots.

Has anyone used capacitive sensing using these types of keypads?

Here, the dome and/or finger movement changes the field. 
(http://www.epectec.com/images/projected-capacitive-touch-panel.jpg)

I don't have the spec on the dome size or distance to the PCB yet.
Also, I may be using a PIC microprocessor.
Any advice is greatly appreciated.

Front view:
(http://g04.a.alicdn.com/kf/HTB1qD2QIFXXXXXRXpXXq6xXFXXXz/szomk-plastic-enclosure-door-access-control-enclosure-case-10-pcs-106-87-30mm-plastic-enclosure-for.jpg)

Internal enclosure parts:
(http://g01.a.alicdn.com/kf/HTB13hzNIFXXXXcIXpXXq6xXFXXXj/szomk-plastic-enclosure-door-access-control-enclosure-case-10-pcs-106-87-30mm-plastic-enclosure-for.jpg)