• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 63 subscribers
  • Views 424 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.

LM5116 abnormal startup

K.Hamamoto
Guru 12155 points

Hi

An abnormal shutdown behavior was observed in the start-up. (left side picture)

It looks like the VCC UVLO or malfunction of the overcurrent.

Vi=36V,Vo=12V,Io=10A    (Vccx is connected to Vout. CS pin is connected to drain of low side FET for Rds sensing)

It is still under investigation, but does such an operation happens when switching to VCCX from VCC?

(right side picture)

Regards,

Koji Hamamoto

  • 0
    TI__Guru 58171 points

    Hi 

    This happens if VCCX voltage is lower than VCC_UVLO_THRESHOLD when internal 'VCCX to VCC' switch turns on. 

    Please connect VCCX pin to ground and connect VOUT to VCC through a diode. (Anode to VOUT, Cathode to VCC)  

    Regards,