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Touch Pin

Posted: Sun Jan 02, 2022 8:55 pm
by d.romeo
Hi, I wanted to ask if it was possible to use the touch pins to detect touch when they are in pull-up or pull down mode with resistor, or more generally when they are not free but connected to an external voltage, for example 3.3V or 1.5V.
Thank you.

Re: Touch Pin

Posted: Sun Jan 02, 2022 11:44 pm
by ESP_Sprite
Likely not. Touch works by charging and discharging the parasitic capacitance of the pad; any non-trivial resistance will wick that charge away.

Re: Touch Pin

Posted: Mon Jan 03, 2022 2:05 pm
by d.romeo
Thank you. Does it also valve if the PIN is connected to GND?

Re: Touch Pin

Posted: Tue Jan 04, 2022 2:21 am
by ESP_Sprite
Obviously. No way to charge anything if the pin is shorted to ground.