• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 135 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.

LM5158-Q1: Variable 20-48V low ripple power supply

danielb
Intellectual 270 points
Part Number: LM5158-Q1
Other Parts Discussed in Thread: LM5158, LM51581, OPA596

Tool/software:

I am designing a variable 20-48V low ripple power supply using the LM5158-Q1 in the Webench tool to bias an optical sensor. I have a few questions regarding this design:

1. I understand that the primary difference between the LM51581 and LM5158 is the peak current. Will the ripple be the same when using either of these ICs?
2. Should I enable the spread spectrum feature to achieve better ripple performance?
3. Is it advisable to use the Hiccup and UVLO features? Do these features affect the ripple?
4. Can I use an LC filter at the output to improve ripple performance?
5. Should I include an input EMI filter as recommended in Webench?
6. Will I achieve better ripple performance if I use the designed power supply to provide Vcc to the OPA596 (currently under preview) and use the op amp output to bias the sensor?

Regards,

 

  • 0
    TI__Genius 15545 points

    Hi Daniel,

    Thanks for reaching out.

    1. Regarding the ripple, there is no difference between these 2 ICs

    2. This feature is meant for better EMI performance and will not affect the output ripple

    3. They will not have an effect as long as they are not triggered

    4. Yes

    5.If you want to pass an EMI test with this design, i would recommend it.

    6. I am not sure if i understand this right. If you use the OPA596 to build a LDO at the output of the boost, the you will have the lowest ripple, yes.

    In the product folder on ti.com, you will find a PSPICE model of this device as well as a testbench that is ready to simulate. With this you could check under which conditions the device bahaves the best. https://www.ti.com/product/de-de/LM5158#design-development

    Best regards

    Moritz