• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 64 subscribers
  • Views 205 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPSM63603: TPSM63603RDHR killed on power on

Martin v KA
Prodigy 70 points
Part Number: TPSM63603

Tool/software:

Hello,

We are using the TPSM63603RDHR to generate a 5V output from a battery supply ranging between 18V and 25V. Unfortunately, we have experienced a high number of board failures during power-on. Some of these boards show a direct short between ground and the power input, while others have no current draw and no output.

We would appreciate it if you could review our schematic and provide any guidance or recommendations to address these issues.

Thank you

  • 0
    TI__Genius 9700 points

    Hi,

    I did not find anything obviously wrong about your schematic. Can you send me your layout as well for review?

    Regards,

    Niranjan

  • 0 in reply to Niranjan Nair
    Prodigy 50 points

    Hi Nair,

    Thanks for your reply.

    I’ve attached two pictures:

    • The first shows GNDA and PGND connected through a resistor, which I believe may have caused the issue.

    • The second shows the same connection made through a net tie Same as the devkit, which we consider the optimized version.

    Could you please review both layouts and let us know if there’s anything wrong with the old or the optimized design?

    Optimised Version :

    Orignal version : 

    Thanks, I appreciate it.

  • 0 in reply to Firas Bannour
    TI__Genius 9700 points

    Hi,

    I would recommend going with the optimised version. The connection between the two grounds is sensitive, hence it is better to go with the layout mentioned in the datasheet. This would most probably be the cause of the issue. Make sure that the connection is only at that single point.

    One other suggestion is to flip the VCC cap (so that it is still close to VCC pin) and move the FB resistors closer to the FB pin. Using long routings can cause an error at FB and hence an error in VOUT. The AGND pin close to FB can also be utilised to make the overall loop smaller.

    Regards,

    Niranjan