Broken arduino uno

[rascupanamuha]

I have arduino uno on my electric scooter. It is connected only to throttle (analog input), motor (PWM output), and to ESC (https://en.wikipedia.org/wiki/Electronic_speed_control) 5.25V output (from 24V battery).

It all worked for 2-3 weeks and today it suddenly stopped working. My computer doesnt even recognize it, small chip near USB connector gets really hot, and only ON led is light

How can i repair it if it is possible, and what do you think it could be?

 

[rascupanamuha]

Small update:
No LED are on except ON led (Tx, RX, pin 13 leds are off)

Everything looks perfectly fine and with other atmega328p chips it doesnt work either. Could it be that ATMEGA16U2 is fried? How can i save my board then?

 

[BioniC187]

Small update:
No LED are on except ON led (Tx, RX, pin 13 leds are off)

Everything looks perfectly fine and with other atmega328p chips it doesnt work either. Could it be that ATMEGA16U2 is fried? How can i save my board then?

Have you tried the 328 in another board?
Have you tried pulgging in to another pc? Though it seems that the16u2 is shorting. Perhaps water damaged or something like that happened. Check it for small pieces of metal that may have gotten and shorted the place between the chip and the board

 

[alec_t]

Possibly a voltage spike from the motor killed it. Does your circuit have adequate transient voltage protection (freewheel diode, TVS diode, generous capacitive decoupling of IC supply rails) ?

 

[mvs sarma]

chip near usb is probably FT232RL and it might have gone as you report getting HOT.

they are available for 2$ or so
a skilled hand and patience are needed to replace it
try viewing some youtube videos how thay remove smd part. and replace by another.

 

[rascupanamuha]

Thank you, i will order it and we will see weather that was a problem

 

[misterT]

Thank you, i will order it and we will see weather that was a problem

Fried component is not the problem. It is only the symptom. Whatever fried the chip will fry the new replacement also.

 

[rascupanamuha]

Maybe not. Because arduino was in my electric scooter, and maybe some metal dust in it caused this problem. I hope so

 

[misterT]

Maybe not. Because arduino was in my electric scooter, and maybe some metal dust in it caused this problem. I hope so

Maybe the same metal dust will fry the new chip.. I hope so.. failing is the greatest learning experience.

 

[be80be]

There is no FT232RL on a uno its a atmega 16u2 AND if your using 24 volts to supply the on board regulator you'll fry it agin.
If you did use the onboard regulator with 24 feed you more then likely fried it and the next chip could be the 16u2 but it may just be the regulator thats bad.

 

[mvs sarma]

Thanks burt,

The O P may upload a close up and crisp photo of his board as it would help. perhaps boards sold in different counties are having different hardware configuration.

 

[be80be]

ATMEGA16U2

The op said it had that chip on it

All of mine use it but there real arduinos , but any way most of the time its not any of the uC that get fried its the power supply that gets cooked

5.25V output (from 24V battery).

If The op hooked the regulator up to the 24 volts there not any real heat sink to handle the heat that you'd get.

 

[mvs sarma]

OH! Thanks again
Then surely I am Off TRACK on the topic. It would be better that i read well before posting any, from now.

 

[be80be]

Heres a pic of ther real deal
If you click it you can see the parts the regulator is a 117-5

 

[Sudheer]

Hi,
If input voltage is hight, like 12v or 24v, use LM7809 to bring down voltage to 9V, then supply to Arduino board. LM7809 has good tolerance for high voltage with rating of 1Amps.

-Suds

 

[april]

Before replacing I would supply 9V to the input plug and see if it powers up Then plug in to a USB for 5V input to see if it goes and then I would supply 3.3 or 5V to the input pins 5V and 3.3V and from those results assess what has gone wrong .
Bit late now but 5V on the 5V pin should still run the chip and if it does not then the ATmega 328 is fried too and probably other stuff as well

 

[Honduras]

I'm kind of interested in how and why you are using a 24 volt power supply. As I remember it, Arduinos aren't rated that high.

 

[mvs sarma]

forget it
old post.
an year or longer than hat

 

[b.james]

Good day Sarma
Yes it's old now . OP has probably taken off
Its interesting though . I regularly put 12 Volt on my Arduinos because its usually convenient using a 12 Volt battery . They don't run out so quickly if you use a car battery.

Am I right in concluding then that ,even at 24V, if you reduce the current draw by say interrupt code and short run times, with long shut down periods to allow cooling, you could get away with it? Or even adding a heat sink to the on board regulator

The trouble with fools is that they do not realise their foolishness.
These forum sitters you have here are a pain . They don't try to help really . What they do is jump in and confuse the thread.
You don't know anything about a situation unless you have experienced it specifically yourself ! Period
I suggest you stop wasting peoples time who come here for an answer.
Leave the answer to someone who does know.

In my case the answer was simple but I found it on a more sensible forum -not this circus

 

[ADWSystems]

I have several projects that will require relays. 9V relays aren't common. Common relays are either 5V or 12V. 5V doesn't power the Arduino well, so that leaves using 12V. Finding a power supply with 9V output isn't common either (except for wall warts, but remember I also need 12V). So I'm going to be forced to use 12V input and am not really in the mood to starting toasting Arduino boards. Have your Arduinos holding up under the 12VDC power supply?