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Hello,
I'm trying to make a simple touch sensor and found several information about this in this forum as well as in the net.
Just for fun, I have put a 10Mohm resistor on a pin of a PIC and I read it just as a button.
It works surprisingly well and I wonder what the "dark side" of this, maybe "too simple" touch sensor is.
Any thoughts about this?
Basically what your reading is the voltage that our bodies carry from the 60hz ac signals in the air along with all the other signals mixed together, as its a 10m resistor its not likely to ever hurt the PIC, but there my be times when it reads a button pushed even if your not touching it since the pin is not either using a pull up or down resistor/cap debounce type of circuit, your just looking at the HiZ input and waiting for your body voltage to tip the scales to a HIGH state. which souds ok, but since our bodys are not alwqays charged this way nor is the air surounding the chip its hard to predict the 100% accuracy. its one of the reasons most touch circuits are capacitive not resistive.
as for the DARK SIDE.. its either going to work or not, its not like your going to turn evil from using the FORCE... :)
Thank you ;-)