TPS56837: TPS56837RPAR-Based Power Supply Board Burns

Milan Domadiya

Part Number: TPS56837

Issue Description:
We are experiencing repeated failures on a power supply board built around the TPS56837RPAR buck converter. After operating normally for some time, the board begins to overheat and eventually burns or becomes permanently damaged. The issue appears after extended operation rather than at startup.

Observed Behavior:

Board functions correctly initially
After a period of continuous use, components near or including the TPS56837RPAR exhibit excessive heating
In some cases, the IC or surrounding circuitry burns or fails catastrophically

Attached images for your reference:

Request:
We need assistance identifying potential root causes—such as layout issues, component selection, thermal design, load transients, or incorrect configuration—and guidance on corrective measures to prevent damage in future revisions.

If you want, I can also help you expand this with logs, measurements, layout notes, or suspected root causes.

Thank you.

Regards,

Milan

2 months ago

0 Haseen Reddy Siripi Reddy 2 months ago

TI__Genius 12250 points

Hi Milan,

We will check and get back on this.

Regards,

Haseen.

0 Manish Gautam 2 months ago in reply to Haseen Reddy Siripi Reddy

TI__Expert 7580 points

Hi Mila,

Kindly share your test condition.

Regards,

Manish

0 Milan Domadiya 2 months ago

Prodigy 20 points

Haseen,

We applied a 12-V input to our board, and it was working normally at first. However, after 2–3 hours of operation, a spark occurred near the IC.

We also noticed another issue on a new board: the board shuts down automatically during operation. After performing a power cycle, it starts again and works for some time.

We are not able to understand the root cause of these two issues in our prototype design. Any guidance would be appreciated

Regards,

Milan

0 Manish Gautam 2 months ago in reply to Milan Domadiya

TI__Expert 7580 points

Hi Milan,

Kindly share the layout file also please share the load current condition.

Regards,

Manish

0 Milan Domadiya 2 months ago in reply to Manish Gautam

Prodigy 20 points

TPS56837RPAR-Based Power Supply Board layout.pptx

Haseen,

Please find the attached document as per required details.

Thanks.

Regards,

Milan

0 Manish Gautam 2 months ago in reply to Milan Domadiya

TI__Expert 7580 points

Hi Milan,

In how many devices you observed this kind of failure?

Regards,

Manish

0 Milan Domadiya 2 months ago in reply to Manish Gautam

Prodigy 20 points

Manish,

Right now, only one device having sparked observed.

did you find anything?

0 Manish Gautam 2 months ago in reply to Milan Domadiya

TI__Expert 7580 points

Hi Milan,

Kindly use less than 6V near to PG pin. Currently you are using 12V it is causing of the damage of the trace.

Also, if possible, you can modify your board.

1. Trace is looking very thin near to pin 1 and 2.
2. Output loop is also big, kindly reduce the loop size.

Regards,

Manish

0 Milan Domadiya 2 months ago in reply to Manish Gautam

Prodigy 20 points

Manish Gautam said:
Hi Milan,

Kindly use less than 6V near to PG pin. Currently you are using 12V it is causing of the damage of the trace.

Also, if possible, you can modify your board.

1. Trace is looking very thin near to pin 1 and 2.
2. Output loop is also big, kindly reduce the loop size.

Regards,

Manish

Hi Manish,

Thank you for the feedback.

Regarding your points:

Trace Width & Loop Size:
Could you please confirm what trace width and loop size you would recommend for this section?
If you can highlight the required trace width and the corrected loop area in the image, that would help me update the layout accurately.
PG Pin:
Also, please confirm if it will be okay to keep the PG pin as NC since we are not using the Power Good signal.

Thanks for your support.

Regards,
Milan

0 Milan Domadiya 2 months ago in reply to Milan Domadiya

Prodigy 20 points

Manish,

If Over-Voltage is triggered on PG pin the, here is what happens and why it affects the PG pin?

0 Manish Gautam 2 months ago in reply to Milan Domadiya

TI__Expert 7580 points

Hi Milan,

!. regarding trace width and copper area you can follow our datasheet recommendation.

2. You can keep PG pin as floating.

Regards,

Manish

0 Milan Domadiya 2 months ago in reply to Manish Gautam

Prodigy 20 points

Manish,

We have applied +12V at EN pin is that also have cause of this issue?

0 Manish Gautam 2 months ago in reply to Milan Domadiya

TI__Expert 7580 points

Hi Milan,

Yes, that one is the major reason for the damage

Regards,

Manish

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TPS56837: TPS56837RPAR-Based Power Supply Board Burns