• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 62 subscribers
  • Views 712 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.

LMZ31710: There is NO OUTPUT in my design, please help to debug!!!!!!!!!!!!!!

user4460468
Prodigy 10 points
Part Number: LMZ31710

In my design LMZ31710 is used to generate 5V from 15V.  schemetic and PCB layout is as below.

when there is no load or the load is light (~1A), the output is normal as designed. However, when the load is heavier (~3A), the output is near 0V.

I tested the VADJ pin in both situation. in light-load situation, VADJ=0.59V; while in the other situation, VADJ~0V.

PCB layout:

TOP OVERLAY:

TOP:

A1:

A2:

BOTTOM:

  • 0
    TI__Mastermind 47060 points

    Hi user4460468,

    To better understand your setup can you provide answers to the following questions:

    • What is your power supply's current rating and what circuits in your system runs off the PS rail?
    • Can you provide scope-shots of Vin, PH, and Vout? 
    • Have you tried shorting out the ferrite bead for the heavier load application?

    Regards,

    Jimmy