Smoke coming from UNO

Ok, so I was attempting to build a 2x4 motor controller and I’m not sure what happened but now My UNO is smoking. I unplugged everything when I first saw it. Now I have removed all wires from the arduino to the breadboard but as soon as I plug the usb cable into it the UNO it begins to smoke within one second. The smoke is coming from The small black ic between the 16mhz crystal and the external power jack, it says 09TlR5R. I was using 12v on the breadboard with the arduino switching the mosfets and connected to common ground. Anyone have any idea what I did and how to fix it?

P.S. I tried replacing the atmega chip on the UNO with a new one but no change.

congrats you make the magic smoke go wild

but now serius

you blew up the 5V regulator i beleve is is an 0.5A version but i cant be shure

what engine did you try to pull out of that little chip?

Well that sucks. So how do I fix it?

wel solder in a new one :P

Is there anywhere I can find a diagram of the UNO pointing out what each component on the board is? I am noob (obvious from the fact that I just smoked my board). I assume that the ic that is smoking is the regulator? Any idea what the replacement part number is?

jeremydial1981: P.S. I tried replacing the atmega chip on the UNO with a new one but no change.

I'm curious: What made you think that replacing the ATMega would fix the issue?

It'd be like not being able to start your car, and replacing the engine expecting that to fix it...

???

:stuck_out_tongue_closed_eyes:

cr0sh:

jeremydial1981:
P.S. I tried replacing the atmega chip on the UNO with a new one but no change.

I’m curious: What made you think that replacing the ATMega would fix the issue?

It’d be like not being able to start your car, and replacing the engine expecting that to fix it…

???

:stuck_out_tongue_closed_eyes:

Im thinking it was a mixture of desperation and ignorance lol.
But on the other hand if the reason you were not able to start your car was a blown engine, then replacing the engine would surely fix it. Mwaahahaha :slight_smile:

I thought the 5v regulator was right next to the external power jack, the IC with 3 legs. Thats not what is smoking. Here is a pic of the smoking part. . .

Smokin UNO.jpg

That part is the Op-amp in my opinion. And it is possible others parts are damage too. You may created what I call : A Domino Effect. Simply change a new UNO board. And Double check and tripple check your wirring of your project. Draw a schematic of your setup. I got the feeling you simply wirring wrong your setup and cause a possible cascade damage of the UNO.

Is there any way to fix it? I would like to try, even if it is just for practice.

Fix it ? You mean fix the board ? Did I said : Domino effect… It mean most of the chips in this board are fry. ← a hugh possibility. If you want to fix it…be my guest. I won’t. To fix it… I will use the method call : shot gun fixing. ← I mean : replace all the components within a hugh area. You know… shot gun… :wink:

Ok well from the sound of it I guess I will just try to salvage anything off of it that I can. So I guess my only question at this point is the same I asked earlier. There are several components on the uno that I don't recognize. Is there any kind of diagram that shows what each component is?

Having just blown two unos, my advice is to be very very careful what you connect where. these things are fragile - I know the second time I put 12v by accident back through a chip - immediate failure. Probably the same thing with the first. The design is very poor.

Schematics & stuff can all be found here. http://arduino.cc/en/Main/ArduinoBoardUno

The only thing you should be connecting 12V to is the voltage regulator input.

The design is very poor.

The board works well for most people. What could be the real problem? :roll_eyes:

garthn: Having just blown two unos, my advice is to be very very careful what you connect where. these things are fragile - I know the second time I put 12v by accident back through a chip - immediate failure. Probably the same thing with the first. The design is very poor.

Actually the arduino boards are just as rugged as most any other comparable board. But lucky for you someone did design, built, and sells an arduino compatible board that was designed to take abuse over and above. So if you can't stop making the mistake of applying voltages above the maximum safe ratings you should consider buying one of these. It does cost a little more but in your case may save you a lot in the long run.

http://ruggedcircuits.com/html/ruggeduino.html

I can't believe any one would say the "design is very poor" Come on here if you fixed this so you couldn't break it it wouldn't be able to do any thing good it would be in a bubble.

You don't put 12 volts on any pin and you don't try to sink or source more power then it can put out.

You wouldn't pull a Mack Truck with a 4 banger car would you if some thing went wrong it would run over you can't stop it.

Same thing here you pulled more power then it could supply and your Mack ran over it.

But the Op may be lucky and he just burned the power supply out by back feeding it

Now finally - that is the first good advice I've had on this forum. If I was an electronics expert I wouldn't have problems - but I am trying to build a platform for my ATM telescope and really don't want to branch out into electronics right now. So I was hoping to get a simple stepper motor working - and thats it. Perhaps the rugged is exactly aimed at me.

Thank you

I guess I'm just too used to (after 30 years) writing software that is idiot proof. But it does take a lot more effort - would be much easier to eliminate the idiots.

In this case, I am the idiot - working late last night - lots of problems at the same time - loose wiring (breadboard:(), discharged battery, driver chip overheating, faulty breadboard, faulty pin on arduino - so finally I reconnected (in a daze) the motor battery to the 5v rail instead of the correct pin. Bang

It's easy to mess up we all do it just some lie about it. But if you fallow so simple rules you going to still have a usable mirocontroller in the end.

Never put power on till you are 100% sure you have the power lines right that's number one and two always check the wiring a few times always.

Three always limit the power to a pin to big of a resistor not going to hurt to small and you'll see smoke.