Board fried?

Hi,

I got some problem with my arduino UNO board. I am not able to burn my program as well as IC is heating up. Although on board LED connected to pin no 13 is also glowing continuously after plugging power to the board. I am not able to understand whats wrong. Any one faced this problem or can give some suggestion...

Thank you.

Yes, time to replace the atmega

ashigupta:
Hi,

I got some problem with my arduino UNO board. I am not able to burn my program as well as IC is heating up. Although on board LED connected to pin no 13 is also glowing continuously after plugging power to the board. I am not able to understand whats wrong. Any one faced this problem or can give some suggestion...

If there's nothing connected to the board then the chip died. Time to replace it.

If chip heats up there are several possibilities:

chip plugged in backwards... check!

chip fried - replace and hope it was only the 328

CMOS latch-up (this will cure itself if you power-cycle the board - caused by driving too high or too low voltages into the input/output pins).

"chip plugged in backwards... check!"
I don't believe that actually kills it - here's what gets connected when flipped:
F - flipped port, N - normal port
F N
b1 c6
b2 d0
b3 d1
b4 d2
b5 d3
avcc d4
aref vcc << aref possibly damaged with 5V applied and no Vcc
Gnd Gnd << Good!
c0 b6
c1 b7
c2 d5
c3 d6
c4 d7
c5 b0
c6 b1
d0 b2
d1 b3
d2 b4
d3 b5
d4 avcc << d4 possibly damaged with 5V applied and no Vcc
Gnd Gnd << Good!
b6 c0
b7 c1
d5 c2
d6 c3
d7 c4
b0 c5

So 2 pins may possibly be damaged from having 5V being applied while Vcc was not.
If other pins had 5V from external sources applied, those might similarly be damaged.

I've plugged in chips backwards a couple of times, then put a big "1" on my duemilanove (back before I went custom everything)
and neither time did the chip get warm, nor damaged that I could tell. I don't recall doing any special testing for d4, and I wasn't doing any analog at the time, but the chip did whatever else I was doing normally.

Putting 5V on Aref might power the whole chip via its protection diode, and probably trigger latch-up due to the high currents on that diode...