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My Arduino has problems!

My Arduino Uno is not doing ANYTHING when hooked up to an AC adapter

Model: PLM05A-050

PIN: 180-0711B

INPUT: 120V~ 0.15A, 60Hz

DC OUTPUT: 5.0V 1.0A

However, when the arduino is hooked up to a usb cable that is connected to a laptop, it works fine. What is the problem?

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The output from your adapter is lower than what is needed for the on-board volt regulator to work. Typically, 5v regulators need an input voltage of 6v or more to work. When using the USB, the volt reg is bypassed because the USB is already a regulated 5v.

     First check whats coming out of the wall wort.  especially the polarity.  Adriano uses Ground on the barrel and V+ in the center.


     Also 5 volts is a bit low for the barrel jack input i use 9 to 12 because there is a regulator on the Adriano.  If you want to use a 5 volt supply you hook it up to the +5 volt and GND pins.

You need more than 5v to run the arduino. Change your ac adapter our switch to batteries (rechargeables preferred) to get the correct voltage of over 6v. 4 non rechargeables or 5 rechargeables (min) should do the job

after looking at the page for the UNO, it looks like one could feed 5v+ into the 5V on the board and gnd to the GND on the board, as long as you weren't planning on using a shield.

hi, you can power the arduino through vin with 7+ volts, this is enough for the on board regulator to provide the 5 volts the board needs. You can also power the arduino directly through the 5 volt pin, however you can only do this with good quality regulated 5volt supplies. If you want to use a wall wart, use a 9 volt one connected to the on board regulator through the power jack. The on board regulator will turn this into a good 5v supply for the board. The regulator drops a few volts while doing it's job, this is why you need 5 volts + 2 volts or more to get a steady 5 volts through the power jack or vin. Duane B Rcarduino.blogspot.com

What happens when I put in like 10v or more? Will the Arduino explode or something?

hi, That should be fine. Duane b Rcarduino.blogspot.com

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