Hi all, Quick question - the specs state "The Arduino Uno can be powered via the USB connection or with an external power supply. The power source is selected automatically." How is the power source selected automatically? Is there an in-chip relay? (perhaps thats a stupid question...) Or some t…

How does the Arduino UNO auto-select USB or DC power?

system September 12, 2012, 12:37am 4

Thanks lefty and doc. Great explanations as always.

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