• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 62 subscribers
  • Views 169 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

TPS62742: Unable to get the correct output Voltage level

Pradeep HN
Prodigy 90 points
Part Number: TPS62742

Hello,
   I have designed a circuit with TPS62742. VIn = 5V. The VEN, VSET1, VSET2, VSET3 and VSET4 are all tied to VIN. I am expecting Vout to be 3.3V. However, I see that Vout is 2.3 V instead. Please find the details of the circuit and schematics below-

I see that Voltage at PG pin is 2.3 V (same as Vout).

Please let me know what could be the problem.

BOM:
L = 2.2uH (part number -  744025002 , manufacturer - Würth Elektronik)
CIN = 10uF
COUt = 10uF

Schematics:

PCB:

  • 0
    TI__Expert 7585 points

    Hi Pradeep,

    Thanks for your question.

    Could you please upload again schematics and PCB images?

    I think that the system didn't recognize them properly and didn't uploaded them.

    Could you please also sends me the waveforms (both at startup and steady state) of VIN, SW, VOUT and PG?

    Thanks,

    Stefano

    All information in this correspondence and in any related correspondence is provided “as is” and “with all faults”, and is subject to TI’s Important Notice (http://www.ti.com/corp/docs/legal/important-notice.shtml).

  • 0 in reply to Stefano Panaro
    Prodigy 90 points

    Hello Stefano,
     Thanks for the response!
    I have attached Schematics and PCB design here as attachment.

    My doubt is related to L1 (inductor: L = 2.2uH (part number -  744025002 , manufacturer - Würth Elektronik), as the recommended Inductor part in datasheet was not in stock.

    PG pin is at Voltage following Vout.

    Thanks and regards,

    Pradeep

  • 0 in reply to Pradeep HN
    TI__Expert 7585 points

    Hi Pradeep,

    Thanks for your feedback.

    I don't think the inductor should be a problem, since it seems very similar to the one reported in the datasheet.

    Both schematic and layout seem fine too.

    It would be very helpful if you could send me the waveforms  (possibly both at startup and steady state) of VIN, SW, VOUT and, if possible, inductor current.

    Thank you and best regards,

    Stefano

    All information in this correspondence and in any related correspondence is provided “as is” and “with all faults”, and is subject to TI’s Important Notice (http://www.ti.com/corp/docs/legal/important-notice.shtml).