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Author Topic: 5V input on pin current restriction  (Read 193 times)
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Emsworth, UK
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I wish to power my arduino from an external regulated power supply hooked  up to the 5V and gnd pins. Is there anything I should watch out for?

Is there a limit of the amount of current I should supply to the pins?

I'm looking at a 5v 2.5A supply at the moment.

Johannesburg. UTC+2
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Faraday Member
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Afaik, current isn't imposed by the supply, it's drawn by the consumer.

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Add a diode from 5V (anode) to Vin (cathode) to avoid reverse driving the regulator.
The board will only draw the current it needs, 30-40mA or so with no IO loads.

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Shannon Member
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Just be sure its a _regulated_ 5V supply, if it outputs more than 5.5V you'll trash the

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