Arduino Mega 2560 external power supply using VIN & GND fails

Development Tools IDE 1.x
1

Hi all, i have a problem with the external power supply.

I connected a rechargable NMH 9v battery to the VIN and GND pins, as documented in http://arduino.cc/en/Main/arduinoBoardMega256
It says:
"Leads from a battery can be inserted in the Gnd and Vin pin headers of the POWER connector."

And also
VIN. The input voltage to the Arduino board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power source). You can supply voltage through this pin, or, if supplying voltage via the power jack, access it through this pin.

But after some hours of testing my arduino cannt be powered externally anymore, it can only be powered by USB.

It seems that some diode does not work anymore, but as stated in the official page, i made everything properly.

Any idea about this kind of problem?

Thanks in advance.

2

Is the battery still charged? Several hours could have discharged it.

3

Yes ii tried with 3 different batteries, 100% charged and also using the jack, but it does not work anymore.

4

Probably the mistake could that i connected the usb and vin & gnd to external power supply at the same time?

I cant figure anything else...but i am new in arduino, so i am not really sure...

5

Casio71:
Probably the mistake could that i connected the usb and vin & gnd to external power supply at the same time?

I cant figure anything else...but i am new in arduino, so i am not really sure...

Hey man! hope you're doing good, same thing just happened to me a few mins ago. I hooked up the leads from my 7.4 V LiPo battery to Vin and GND pin headers, and some diode burned off. Battery had a charge of 8.23 V so it's still in the range (7-12 V), so I don't know why those pins are not working anymore.

I'll appreciate any comments on this.

Regards

6

By the way, does anyone have an idea of which is the maximum input current allowed by these pins (Vin & GND)?

7

Rodolfo, did you connect vin and gnd at the same time than the usb connection?

(I did)

I wonder if this could be the problem.

8

Casio71:
Rodolfo, did you connect vin and gnd at the same time than the usb connection?

(I did)

I wonder if this could be the problem.

No, I didn't. I connected only the external power source (LiPo battery).

But based on my experience, I can tell you that connecting both power sources at the same time (battery and usb) is not the problem. I did that before, I'm guessing that the problem might be the voltage supplied by the battery (in my case 8.21 V), so that the Arduino power summary (documentation) might be wrong in what external power source range (7-12 V) refers.

Or it might be the output current coming from the battery, but there's any warning about it,

Regards