Help, ASAP!

Other Hardware General Electronics
1

Hey! Thanks for coming! I need help with my Arduino UNO.

So, I got this cool breadboard, with a 5V out plus ground along the positive and negative lines. Then, I did something super smart and clever and plugged the breadboard's 5v and ground lines to the Arduino's! (Can't remember the exact schematic, but it was pretty "cool" in my eyes). Well, long story short, the lights went crazy, and before I could do anything, POP. SMOKE. Arduino went black. I did something I knew was stupid and plugged it into my PC, which fortunately didn't hurt anything. The TX and RX lights went bright, and it started running the code that was on it when I last programmed it. The computer didn't see it, and I knew that I blew the serial converter.

After this horribly stupid and amateur story, do you think there is any hope for my precious UNO?

Please respond ASAP!

2

Sounds not - unless you have some spare parts and a hot-air solder rework station.

3

I reckon it's probably toast at this point. The Atmega328p may be okay (in fact it probably is), but there are likely multiple damaged components on the board. Without hot-air rework and a lot of effort (more than the board is worth), you're not going to get it working again.

You can (and should) connect grounds, but don't ever connect two supplies together directly - even if they're nominally the same voltage, they won't be exactly the same, and will fight eachother.

4

Aww... Okay... :frowning:

5

OP has learnt a valuable lesson. Check all wiring at least three times before turning on the power! :slight_smile:

Weedpharma

6

weedpharma:
OP has learnt a valuable lesson. Check all wiring at least three times before turning on the power! :slight_smile:

Weedpharma

Or keep spares on hand :wink:
That's a sure fire way to avoid trashing anything

7

If your Uno has a 28 pin DIP mounted 328, it can probably be salvaged for a bare bones board. If not, you might be able to program it using a USB ISP cable but that will cost you about as much as a Chinese Uno clone. And you won't have the Serial monitor available.

8

pegwatcher:
If your Uno has a 28 pin DIP mounted 328, it can probably be salvaged for a bare bones board. If not, you might be able to program it using a USB ISP cable but that will cost you about as much as a Chinese Uno clone. And you won't have the Serial monitor available.

Or serial, period, it sounds like (at least without cutting traces) - since he says when he powered it afterwards, the TX and RX lights went on, implying that the serial lines are shorted to ground.

9

Actually, there are two interesting observations here.

One is that plugging actual 5V and ground correctly to the Arduino will not cause any problems at all. It follows that was not what actually happened.

The second follows closely. Something has happened to the board. But without a lot more information, we have no idea what it was and how severe the damage is. It may be one single cheap component. If it smoked then it should be perfectly obvious what component that was for starters.

10

Paul__B is right - connecting a separate 5V correctly won't kill your UNO - you did something else. Reversed connections maybe?

Either way, sounds like it's gone to Arduino heaven. :frowning:

11

What if you pull the on-board regulator and then you supply 5 Volts externally?
This will allow you to determine if the onboard regulator is bad or something else.

ajfreed00:
Hey! Thanks for coming! I need help with my Arduino UNO.

So, I got this cool breadboard, with a 5V out plus ground along the positive and negative lines. Then, I did something super smart and clever and plugged the breadboard's 5v and ground lines to the Arduino's! (Can't remember the exact schematic, but it was pretty "cool" in my eyes). Well, long story short, the lights went crazy, and before I could do anything, POP. SMOKE. Arduino went black. I did something I knew was stupid and plugged it into my PC, which fortunately didn't hurt anything. The TX and RX lights went bright, and it started running the code that was on it when I last programmed it. The computer didn't see it, and I knew that I blew the serial converter.

After this horribly stupid and amateur story, do you think there is any hope for my precious UNO?

Please respond ASAP!

I agree with PAUL__B and OldSteve ...

But, can you or someone you know replace the Serial Chip?
Does it look burn't?

Also, you may need to replace the On-Board 5V Regulator Chip.
Does it look burn't ?
Can you run the board using the 7+ Volts Power Jack?

Sounds like the external power supply was connected backwards.

Connecting two 5 Volt Power Supplies, in parallel,
after they are both ON, will not cause them to "fight".
The "Higher Voltage" power supply will simply supply most or all of the amps.
The "Lower Voltage" power supply will essentially go idle.

The CPU chip was definitely screaming, OUCH !!!
Hard to know what internal damage, if any, was done to the CPU Chip.

12

I think it depends on whether it's a clone or a 'real' Arduino, as to whether or not it's worth wasting time on, too.
My UNO clones, (exact replicas w/ ATMega serial chips), only cost AU$8 each delivered, so if I fried one, into the bin it would go, and I'd order another.
Originals are a bit more expensive, so might be worth the effort.