J721EXCPXEVM: product quality problem

Hi,

Have you tried booting that board? Inserting SD card with the default binaries? After how long does the LED turn Red. More details
will help analyze this better.

Best Regards,
Keerthy

I try to boot the board many times. But, the LED on the board  turns red in less than one minute. At. present, SD card is not ysed by default. 

So,  can this problem be solved? Due to time constraints, can you give us a reply as soon as possible. Thank you very much.

The LED that turns RED, I assume you are referring to LD3?  If yes, this indicates the input voltage is out of range.  What power supply are you connecting to the EVM?

HI,

Yes, The LED3 near the switch turns red. The power parameter is input 220 and output 12v. Details can be found in the picture. Please give a reply as soon as possible。 Thank you very much.

How much current can the source produce at 12V?  If you will monitor the input voltage at the connector while running, you may see the voltage drop due to higher current demands from the EVM, or due to excessive resistance in the power supply cable as it heats up.  My guess is the voltage is dropping over time, causing the LED to turn RED once the voltage at the connector drops below a threshold.

Hi,

  12v can produce produce 5mA current. If  it's like you said, can we exchange the goods? Can chip damage cause this phenomenon?

5mA of current is not sufficient to supply board power.  As stated in the user guide, we recommend a 60W power source (12V at 5Amp)

Hi，

  Sorry, we provide a 60w power source ( 12V at 5Amp). So, Is the chip of the board broken?

From the image you provided, the power connect appear to use fairly high resistive path (gator clips, long wire, etc).  Have you verified the input voltage at the board is within spec when the RED light is on?  Its possible as the wire heats up (due to current flow and high resistance) - the voltage drop because large and cause input voltage drop.

These systems are tested prior to shipping. Board failures are rare.

Hi.

As you said, board failures are rare. We found that the board was short circuited after the test, but we don't know the reason. So, this situation how to deal with. Or, you can repair it. Thank you very much.

I'm sorry, but I still have no confirmation the board has an issue.  From the image you provided, the power connect appear to use fairly high resistive path (gator clips, long wire, etc).  Have you verified the input voltage at the board is within spec when the RED light is on?  Its possible as the wire heats up (due to current flow and high resistance) - the voltage drop because large and cause input voltage drop.

You mentioned a board short was found.  Can you provided more details?  Where was the short?  On what power rail?