Hello,
I am using tactile buttons. I am using the pull down configuration with a 100ohm resistor going to the digital pin and 10K going to ground, as per the tutorial. I am just curious as to why we are using only 100ohms. Would this send 50mA to the digital pin and exceed the max current value the pin can handle? Also if it were 50mA would a 1/4W resistor be insufficient? Please correct me if I am looking at this wrong. Thank you.
resistor values for buttons
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resistor values for buttons
by jonatj » Thu Apr 05, 2012 10:08 pm
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Re: resistor values for buttons
by jonatj » Thu Apr 05, 2012 10:16 pm
I may have answered my own question, but still a verification would be nice. The pins when configured as an input are high impedance and take very little current. Therefore the pin is not actually being supplied 50mA.
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Re: resistor values for buttons
by adafruit_support_bill » Fri Apr 06, 2012 4:59 am
The pins when configured as an input are high impedance and take very little current. Therefore the pin is not actually being supplied 50mA.
That is correct.
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