• State TI Thinks Resolved
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 64 subscribers
  • Views 18 views
  • Users 0 members are here
Support feedback
Options
Options
Related

LM5149-Q1: EMI request

Tommy Tzeng
Genius 5780 points
Part Number: LM5149-Q1
Other Parts Discussed in Thread: LM5149, LM5148, LM706A0

Tool/software:

Hi Sir,

may we understand some the quesiton? current customer specification as below:

Vin=+48v, Vout=+5.3v/10A(max). customer want to optimize the current solution, this power supply is use in a TDD system, provide the main power to the DC/DC and RF, and to improve the following points:

1. the goals are to reduce output capacitance and minimize generated EMI interference,

2. while maintaining fast load transient response and keeping ripple within 1%, at the smae time, efficiency must be preserved.

we found comparsion table between LM5148 and LM5149, can the DRSS and AEF function help improve the above issue?

  • 0
    TI__Expert 5805 points

    Thanks for your question. 

    We will look into it and get back to you. 

    Thanks and Regards,

    Naresh

  • 0
    TI__Guru 73742 points

    Hi Tommy,

    The LM5148 and LM5149 are similar (both have DRSS), but the LM5149 also has AEF. I would go with the LM5148 here, as the AEF is more helpful for EMI filter inductor reduction at Vin = ~12V than at 48V.

    Please follow the data sheet and EVM PCB layout guidelines. Also, see app note SNVA803 for input cap placement relative to the FETs, which is important for a buck regulator.

    PS: Take a look a the LM706A0 65V/10A converter with integrated FETs and likely better EMI than a controller-based solution.

    Regards,

    Tim