Powering the Nano and Mini Pro

Hi guys, I need a really small power supply for Nano and Pro Mini because I need to enclose everything in a very small case. Do you thing that something like the 2 down here could be ok? I just need to power the board plus a 5V relay.

http://it.aliexpress.com/item/5V-600mA-3W-AC-DC-Isolated-Power-Buck-Converter-AC-220V-to-DC-5V-Step-Down/32536022737.html?ws_ab_test=searchweb201556_6_79_78_77_80_61,searchweb201644_5,searchweb201560_10

or

http://it.aliexpress.com/item/5V-600mA-3W-AC-DC-Isolated-Power-with-Box-Buck-Converter-Constant-Power/32537651966.html?ws_ab_test=searchweb201556_6_79_78_77_80_61,searchweb201644_5,searchweb201560_10

or maybe I'll just disassemble this: http://it.aliexpress.com/item/5V-1A-EU-AC-Travel-USB-Wall-Charger-for-iPhone-5-4-4S-for-Samsung-Galaxy/32244607195.html?ws_ab_test=searchweb201556_6_79_78_77_80,searchweb201644_5,searchweb201560_10

Thanks, Andrea

Yeay, you're fine (as long as the relay isn't some kind of big ass relay...) I use USB chargers all the time :) Only don't connect it to the RAW pin but to the 5V pin.

septillion: Only don't connect it to the RAW pin but to the 5V pin.

Why that?

Because USB power packs produce 5 V, so you need to feed that to the 5 V “VCC” pin on the Arduino.

But if I use the other power supply which I'm unsure about the stability of its output, isn't better to put it in the raw pin?

Yes, as long as it is at least 7 V, and not more than 12.

Oh, got it. This for the nano and the pro mini?

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