• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 63 subscribers
  • Views 598 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.

LM3150: Inductor size limitation - Need Recommendation

Andy Snawerdt
Intellectual 2260 points
Part Number: LM3150

Hi team,

I am currently working with a design that has the following specs:

  • Vin = 12V
  • Vout = 6V
  • Iout_max = 15A

Based on the datasheet, I have come to the conclusion that in order to follow the restraint of t_off  > 725 ns, I require a switching frequency that is less than 690 kHz. With this in mind, I was able to calculate ET for varying switching frequencies, and determined that my inductor of choice would fall in the range of L43, L44, or L45 (depending upon the switching frequency I end up going with). The datasheet recommends the following inductors for this case:

  • HA3778-AL from Coilcraft for a 1.5 uH solution
  • B82477-G4102-M from EPCOS for a 1 uH solution

However, both of these are too tall for my design. Therefore, are there any recommendations for a shorter inductor that can still work for this design? I did some research myself and landed across the XAL7020. However, this is so small, I was worried it may have other negative effects that I am not considering.

Let me know if there are any other inductors that would fit this criteria, or whether the XAL7020 will work and I am just being to cautious.

Thanks!

Andy

  • 0
    TI__Mastermind 23845 points
    Hi,

    Have you checked your design parameters with webench? You can enter the design parameter and see what the value that webench recommend. The inductance value will be inversely proportional to the frequency that you choose. Therefore a larger inductance is needed if you operate at lower frequency. As for XAL7020, i believe as long as it can handle the current, it should be ok. Keep in mind that the inductor has to be able to handle the current limit that you set.

    Thanks
    -Arief