URGENT URGENT URGEEEENNNNNT: My DE2 borad BURNED and i don't know what to repair!!!

[Altera_Forum]

Hi guys, 

I'm only couple of weeks away from my graduation day and i'm working on a project to control multi-cars elevator system using NIOS II which was working just fine today untill......... Suddenly, the board halts then the GOOD led turned off and the red/green leds gave a week light much like they seem when you download a design to the board. after while, i've tried to turn it on again, i've noticed that if i press the red button smoothly enough the board would turn on just fine, but that gave me a hope of only few minutes. now, the ON led also turns off a short time after pressing the button and i'm hearing a wierd noise from the supply circuit at the corner of my board (i've heard that noise before but now it gets like a higher frequency).  i've googled a bit about the problem and i've found people talking about the TC3 capacitor but that's not my issue as i don't have one on my board (recent boards don't have TC3 capacitors). all i did is to test the supply cable and it "sadely" is fully operational. now i'm REALLY depressed as my graduation day is really close and the worst just happened!! :cry: i guess what i'm trying to say is.... PLEASE HEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEELP! and i'm mentioning everyone to give a suggestion to my acknowledgement :o .

[Altera_Forum]

Hi, keep cool..... Use The Force, Obiwan ;-) 

 I think you have connected other components to the board, haven't you ?  Have you succeeded in configuring the board with "factory design" : one press button somewhere ?  maybe you have short circuits that FPGA has supported for a long time : 20mA per pin without exceeding ...mA per Bank....  In you project setting, did you set unused pin as input tristated ? unused pin as output driving ground is the option by defaut (Quartus 9) and is good for noise immunity. Input tristated prevents unintentionnal short circuits.  I suggest you to unplug all other components so as to identify more precisely the problem.  Pressing the button smoothly is likely to produce bounces and FPGA is repeatedly reconfigured (100ms to Power On Reset on FPGA cyclone II), during this time FPGA is tristated (to allow hot socketing) and output buffers have the time to evacuate calories.    I suggest you to check carefully in/out pins association in your design and test separatly other components that you have plugged to the board.  Gooooooooooooooooooooooooooooooooooooooooooooooooooooooooood luck. Use you instinct, your brain, you hands

[Altera_Forum]

thanks mmTsuchi, yes i was connecting other components to the board but now i'm only dealing with the board alone (not even connected with PC) which was working fine for the last three months by the way. could you suggest any steps or tests to repair the board?

[Altera_Forum]

thanks mmTsuchi, yes i was connecting other components to the board but now i'm only dealing with the board alone (not even connected with PC) which was working fine for the last three months by the way. could you suggest any steps or tests to repair the board? 

ps/ i believe i've shorted some unused pins from the extension headers today (not Vcc or GND). but i assumed that it won't be a problem as they're set as outputs driving ground, was i wrong doing that?

[Altera_Forum]

I highly suggest you to set "unsued pin as input tri-stated" and recompile then redownload your design. 

 On extension headers, there are GND and VCC that could be unintentionnally shorted with an unused output pin which is driving to GND.   With a factory design, did you still hear noise from power supply ? In order to see if your board is burnt or not.

[Altera_Forum]

maybe i wasn't clear, the board can't be turned ON at all. only the ON led is turned on for a really really short period (which gets shorter every time i try) then it turns off as well.

[Altera_Forum]

Ah OK. 

 You can supply power by a "laboratory power supply" to see if it is your board or if your power supply is disfunctionning.  Did you smell something very hot on your board : FPGA, 3.3V regulators, 1.2V regulators...  You can also make FPGA tristated by pulling down the Chip_eneable_n FPGA pin with a 1kOhm resistor to GND. This pin is available on Active Serial header (pin number 6 but i am not sure) did you smeeeeeeeeeeeeeeeell what the rock is cooking ? :cool:

[Altera_Forum]

i don't get it, what do you want me to supply power to using the laboratory power supply? 

there's no smells coming out of the board. just the tense noise from the supply circuit at the top left corner.

[Altera_Forum]

The board is shipped with an adaptator, 

With the laboratory power supply, you can see value of current which shouldn't exceed few Amperes.  But you hear high ferequency little noise at the top left corner of the board. I don't have the board under my eyes, I think there are regulators, ferrite selfs, capacitor...  Did you voltmeter/scope the 5V, 3.3V, 1.2V.   Search for an other board :-P

[Altera_Forum]

Oh Dear.  

Good luck debugging this. Its going to take time and effort. If you're in a rush, it would be quicker to buy a new board.

[Altera_Forum]

Ok, i've got some help from the maintenance lab of the university, the board now can be turned on again. but only the power blue led is on..still, i can download any design i want to the RAM and work with it without using the burned inputs of the board ( GPIO_1[9 -> 13], key[0 + 2], sw[1 + 2]). also, i've noticed that the initial program that is supposed to be run from the eeprom -the counter with the hello message on the lcd- is not running any more. when i tryed to load it again with the run/prog switch set on prog. the downloading process halts at arround 64%. 

i should also mention that the noise now disappeared and the L4 inductor bellow the red power button gets very hot rapidely after turnning the kit on so i'm trying not to keep it running more than 4 to 5 minutes at a time not to burn it all, or can i run the board without worrying about that? too bad i can't get another board cause they're not available arround easily, very expensive and the board i have belongs to the university so i kinda have to stick with it till i finish my project ;)