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Topic: Problem with analog input (Read 122 times) previous topic - next topic

tonchek

Hi! I need help. Is it possible that using digitalWrite to turn on LED makes my analog input reading wrong? 

jremington

#1
Jul 22, 2019, 12:14 am Last Edit: Jul 22, 2019, 12:15 am by jremington
Yes. If you don't have a current limiting resistor (about 150 Ohms minimum) in series with the LED, you could be overloading the Arduino output and voltage regulator, which would affect analog input readings, as well as destroy the LED and/or the output pin.

Wawa

Is this for your love-o-meter from your other thread.
Cross-posting is against forum rules, and wastes time.

If the current resistor for the LED is not there, or has a too low value, or the Arduino supply drops for some other reason, then the TMP36 temp readout increases.

Even if you have done it right, those starter examples are usually written in easy (bad) code.
Post the code (or a link to it). We might be able to improve it.
Leo..

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