• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 62 subscribers
  • Views 689 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.

LP5912: Voltage regulator IC Transient Response Issue, LP5912-1.2DRVR & LP5912-1.1DRVR

user4773176
Prodigy 100 points
Part Number: LP5912
Other Parts Discussed in Thread: LP5907

We use linear voltage regulator IC, LP5912-1.2DRVR & LP5912-1.1DRVR, in our product.

By our customer request, we need to measure the Transient Response.

Vin is 1.8 V, ΔV is much higher than the spec. But the we can’t measure a result as same as your spec.

The image below is our measurement result and TI SPEC.

We need your help to clarify this issue. Thanks.

  • 0
    TI__Mastermind 23361 points

    Hi, 

    The datasheet plot shows a 30mV droop during the load transient while in your test, the droop is around 70mV (correct?).

    One difference I've noticed from your plot is that it contains more rings than the datasheet one. The ringing is normally due to inductance from the cable that carries the load current and the added inductance could result in more droop during load transients. How long is the cable from the output to the load? I would suggest minimizing the cable that connects the load to the output of the LDO. 

    Regards, 
    Jason Song

  • 0 in reply to Jason Song
    TI__Prodigy 100 points

    Yes, we also use LP5907SNX-2.8/NOPB in our device. The load transient result of LP5907SNX-2.8/NOPB meets specifications in the same measurement method.

    Because the cable from the output is really short and the result in different LDO is fine, I think it isn’t the reason.

    This is the load transient result of LP5907SNX-2.8/NOPB.

  • 0 in reply to user4773176
    TI__Mastermind 23361 points

    Hi, 

    It's hard for me to read the slew rate of the load when applying to the LP5907 and LP5912. The plot you shared for LP5907 does not seem to have the same ringing effects on the one in LP5912. Will you be able to share a photo of your setup for me to have an idea on what else could possibly be improved? 

    Regards, 
    Jason