Power arduino with an external battery!!!

Hello all, i wanted know if you can turn Arduino with external battery!!! Thank you!!!

Yes you can! :slight_smile:

I am using arduino uno. It has a port named as "Power". At that port there are pins available for 5v and GNG. So you can connect those pins to your external battery. I have tried it and it works fine.
Regards

Thank you for replies, how many ampere can absorb arduino?

totonno87:
Thank you for replies, how many ampere can absorb arduino?

Approimately 50mA...plus whatever you connect to it.

Instead of using the external power port, I tend to like the rechargeable batteries meant for cell phones and plug in the USB cable to the battery and the USB port on Arduino. I bought a unit with 5000 maH unit with two USB ports, and it lasted about 4 days running blink with no power conservation techniques.

If you do want to use the external power connector, I would suggest not using the 9 volt batteries sold for smoke detectors, since those don't hold much charge, and you will continually need to buy batteries. I do keep a few 9v batteries that I take off of my smoke detectors that I use the battery until they are fully drained. You can get cases that hold 6 rechargeable Nimh AA batteries fairly cheaply, which provide typically 7.2v to the power port, or 8 AA batteries which provide 9.6v in case you need to power things like motors or servos as well as the Arduino.

It's amazing that people rarely talk about applying power at the "Power Jack", but seem
to talk a lot about applying voltage at the Power header, especially to the 5V pin, and
which bypasses all of the protection circuitry built into the board. Can't figure it out.

If you hook any battery at all to the 5V pin, you'll never ever get a proper 5V on the 5V
buss of the board. ???????

oric_dan(333):
If you hook any battery at all to the 5V pin, you'll never ever get a proper 5V on the 5V
buss of the board. ???????

It doesn't need to be 5V. Anything between 1.8-5.5V will run the chip.

(Whether or not the attached devices will be happy is another thing...)

I connected 12v to the external power jack and noticed the board LEDs seemed brighter. Checked the voltage on the board 5v pin and it was ~8v! The external power circuit seems to be somewhat of a tutti-frutti design.

zoomkat:
I connected 12v to the external power jack and noticed the board LEDs seemed brighter. Checked the voltage on the board 5v pin and it was ~8v! The external power circuit seems to be somewhat of a tutti-frutti design.

Well that seems more like a on-board voltage regulator fault or failure. A operating regulator should only have 5v output with a 12v input, as that is certainly within it's operating limits.

Lefty

If you hook any battery at all to the 5V pin, you'll never ever get a proper 5V on the 5V
buss of the board.

Why not? That pin IS the 5V bus on the card. Whether that pin is supplied from the 5V regulator, the USB port, or directly from outside, the devices connected to it will not see a difference, and devices connected to IO pins will not see a difference.

I would put a 1N4001 diode from 5V (anode) to Vin (cathode), the currently used regulator NCP1117 is susceptible to damage from being reverse driven.

Zoomkat, sounds like you have a busted regulator.

CrossRoads:

If you hook any battery at all to the 5V pin, you'll never ever get a proper 5V on the 5V
buss of the board.

Why not? That pin IS the 5V bus on the card. Whether that pin is supplied from the 5V regulator, the USB port, or directly from outside, the devices connected to it will not see a difference, and devices connected to IO pins will not see a difference.

I don't understand this comment. If you hook a battery directly to the 5V pin on the Power header,
how can you still expect to have 5V?

Zoomkat, sounds like you have a busted regulator.

I then powered the board with another 7805 connected to the arduino 5v pin and things then worked as expected. The arduino was an early ebay board, so the onboard 7805 could have been bad from the start.

"If you hook a battery directly to the 5V pin on the Power header, how can you still expect to have 5V? "
I see what you're saying. I interpreted that as "any 5V source" and not so much a battery literally.

You can have a 5V, or nearly 5V battery, connected - such as 4 x 1.2V NuMH batteries, for ~4.8V.
Or a battery or two with a boost converter, such as

Nauman048:
I am using arduino uno. It has a port named as "Power". At that port there are pins available for 5v and GNG. So you can connect those pins to your external battery. I have tried it and it works fine.
Regards

And the current answer from the Arduino product people is:

5V.This pin outputs a regulated 5V from the regulator on the board. The board can be supplied with power either from the DC power jack (7 - 12V), the USB connector (5V), or the VIN pin of the board (7-12V). Supplying voltage via the 5V or 3.3V pins bypasses the regulator, and can damage your board. We don't advise it.

Of course this topic has been discussed so often in the past, to no satisfactory conclusion for all.

Lefty

if you can turn Arduino with external battery!

Yes.

It is actually quite difficult to turn Arduino with internal battery.