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Author Topic: Analog read micro amps  (Read 685 times)
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Can the analog input read micro amps between 50 and a 100 ua. I am building a cloud charge monitor and the base setting is 50ua and goes up when a charged cloud passes over. I would like to make LED's light up as the micro amps increase. Using a Uno
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Can the analog input read micro amps
No it only reads voltages and only in the 1mV region at that.

You need to use op-amps to get the signal up into the volt level.
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The problem is the AREF voltage you are referencing against and the quality of the ADC of the Atmel chip.

If you are referencing against 1.1v ( like I am with a Mini pro) then 1100mv/1024 steps results in just over a 1mv step.


The other issue you may get is "noise".

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Resistor is a sensor, that transform current to voltage to be measurable by arduino.
All you need R, 5 - 10 kOhm to get V 0.5 - 1 V by Ohm law V = I x R
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