Why do capacitive keypads perform so erratically?
Capacitive keypads (analog) are all basically the same (we know, we designed and patented capacitive systems as far back as the late 80 s!). Analog traces are run from a touch pad back to a special IC loaded with self-calibrating software. When the environment changes (temperature, ESD, electrical noise from motors and LEDs, moisture on the keypad, etc), the software algorithm kicks in and slows down the touch response in order to determine if a pad has been touched or not.
