Board is dead!

[jemzik]

Hello
Today my board stopped responding by all means!
No light, no serial , no lan !
Heat sink gets warm but not as hot as when it was functioning properly
Happened when I tried to turn it on this evening!
I changed couple of power supplies but no sign of life !
Could you post power supply rail of RP so I'l try to figure out what happened to it.
Thank you

[jemzik]

Today LED 8 showed up when I connected power cable to the board . Also COM port of RP recognized in system but no output to serial console.

[redpitaya]

Hi,

Here are the test point voltages, you can check them first.

TP1
3.3 V
TP2
2.7 V
TP3
2.6 V
TP4
D- (micro USB connector)
TP5
D+ (micro USB connector)
TP6
D- (USB connector)
TP7
D+ (USB connector)
TP8
5 V
TP9
5 V
TP10
5 V
TP11
GND
TP12
GND
TP13
5 V
TP14
3.3 V
TP15
1.5 V
TP16
1 V
TP17
1.8 V
TP18
-3.5 V (- 4 V)
TP19
NC
TP20
GND
TP21
GND
TP22
GND
TP23
2.5 V

Best, RP

[jemzik]

Thank you for response!
Following Test Points are dead:
TP2 and TP8 .
SMA connectors are getting as hot as heatsink of FPGA
NXP wave form generator also gets hot faster than FPGA

[redpitaya]

Hi,

TP8 is directly on VCC from micro USB connector.
Do you have week power supply or recommended 5V/2A.
If you have something in short circuit, then protection should turn off all voltage rails.

TP2 is from FPGA .

Best, RP

[jemzik]

Changed couple of power supplies . All of them are rated up to 2 A at 5 VDC (including original that comes in kit with RP)
As I mentioned before there is definitely some kind of short around NXP chip and "signal out" SMA connectors
they are getting very hot very quickly ( less then 30 sec.) where FPGA still cool . It never happened before .

Can not find any reference about NXP chip . It should be some kind of waveform generator and it may be possible to try to change it , it worth the attempt.

[pavel]

Hi,

I've also heard about a similar problem from another Red Pitaya owner. The DAC chip stopped working on his board. He suspected an overheating problem and installed a cooler fan on his new board.

The NXP chip is probably the dual DAC (NXP DAC1401D125). Here is a link to its datasheet:
http://www.nxp.com/documents/data_sheet/DAC1401D125.pdf

Cheers,

Pavel