TMS570LC4357: Problem with the HDK

Hi Guru prasad,

What is the issue?

Is 3.3v and 1.2v LED's on the HDK board are not liting? 

Is 12v and 5v LED's are liting?

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Thanks & regards,
Jagadish.

Yes 3.3v and 1.2v led are not working 

Hi Guru Prasad.

Is 12v and 5v LED's are working?

If it is not the issue with capacitors, then it might be the issue of either 5v to 3.3v or 3.3v to 1.2v regulator issue.

And i am from TI-Bangalore only but i think here we don't do any PCB service. I will check with my hardware team once and get back to you on this.

And also, please let me know, board working status after immediate receiving of it? Because TI will test all the boards before it shifts to the customers.

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Thanks & regards,
Jagadish.

Hello sir ,

These are the only lights that glow up after the board is turned on .Initially we had the set of lights that used to glow up but now only this lights glow up .And also while dumping the code it says debug probe error .
yes sir please check with your team and let us know if there is any near by service center which could help us resolve our issue with the board.

Could i please get a response for this?

Hi Guru prasad,

Apologies for the delay in my response.

I Just checked with my hardware team, and we don't have any hardware service in Bangalore. 

And i can only guide you in solving the issue, as per my understanding 

As you already checked the capacitors parallel to the 3.3V, so the issue now can be due to the regulators, i mean it could be due to either 5v to 3.3v regulator (U39) or 3.3v to 1.2v regulator (U35).

I am suspecting these two ic's because 3.3v and 1.2v LED's may not lit either U35 shorted internally or U39 opened internally, in these two conditions these LED's may not lit.

So, my first suggestion would remove the 3.3v to 1.2v regulator (U35) and verify the 3.3v supply, if we got 3.3v supply means we can directly change the U35.

If still 3.3v not get then it could be the issue of U39, so you need to change the U39.

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Thanks & Regards,
Jagadish.

Will check with this suggestion and get back to you .
Thank you sir

As suggested earlier we have removed the U35 and U39 also has been removed but still the condition of the board is the same. It is showing short between 3V3 and Gnd .
what might be the problem ??

can i further get solutions for it sir ??

Hi Guru prasad,

I really thought it could be due to the regulators, but it turns out something else now.

Can you please also check below capacitors:

C68, C107 and C83?

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Thanks & regards,
Jagadish.

Hello sir,

As suggested earlier we have removed the capacitors but still there is short present between the 3V3 and gnd.

Can i please know to proceed further now?

Hi Guru Prasad,

I too confused now, in my previous similar issues, we confirmed it as either capacitors or regulators but now in this case it looks like either of them not causing the issue and it is turned out something else.

I don't know what else we can do now, i will try to get some hardware team support for this.

And before that, i want following confirmations from you:

1. Did you remove all the capacitors and verified the 3.3v LED? Is the LED still OFF?

2. Did you remove the 3.3v to 1.2v regulator and verified the 3.3v LED? is the LED is still OFF?

3. Did you try to change the 5v to 3.3v regulator with new one and verified the 3.3V LED?

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Thanks & regards,
Jagadish.

Yes sir we have done all the above mentioned things.

After checking the entire board we found out that there is a short between 3v3 and gnd.

Now my question is sir even if we try debugging the board and remove the short and change the IC, Will it still work fine?

The short is between C68, even after the removal of all the above capacitors and regulators you have mentioned there is still short present even after removal of the capacitors and regulators.

Is there any replacement available from the companies side .

Hi Guru Prasad,

Guru Prasad said:

Now my question is sir even if we try debugging the board and remove the short and change the IC, Will it still work fine?

Controller should work. If 3.3v and GND got short means mostly the 5v to 3.3v regulator will get damage because it should need to source more current than what it rated. But controller should not have any issue.

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Thanks & regards,
Jagadish.

So, you say is we can replace the ICs that are connected to the 3v3 and gnd right ?

Hi Guru Prasad,

No need to replace the all the IC's connected with 3.3v and GND,

usually in these types of cases, source will get damage due to the short. So, first try to replace the 5v to 3.3v regulator (U39) after removing the short between 3.3v and GND. That should solve the problem.

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Thanks & regards,
Jagadish.

Ok Sir

Sir is there any replacement of the board ?

Guru Prasad said:

Sir is there any replacement of the board ?

I don't know that either sir, all i can provide is application support.

Can you try to check with local sales team?

What do you mean by local sales team?

I don't know exact link either,

Can you please check in ti.com, you might find sales team by region.

As the board is working initially and got issue after in testings right so usually, they may not replace with the new board.