• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 30 subscribers
  • Views 303 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.

IWR6843: Single or Multiple Antenna Help

Dajon McGill
Expert 6861 points
Part Number: IWR6843

Hey Team,

I am trying to assist a customer that is considering using 1 or 3 IWR6843 antennae for vital monitoring.

They mentioned that the IWR6843 uses the LP87524JRNFRQ1 for its PMIC chip with no LDO but there is another version that uses LP87524BRNFRQ1 but with 2 LDOs (to clean up RF power).

Would any of these 2 configurations (J or B PMIC ICs) provide differing results for 1 antenna and 3 antennae operation? If the customer goes with 1 antenna operation, does each version (J or B) have advantages? 

Thanks for the help!

Best,
Dajon McGill

  • 0
    TI__Mastermind 25835 points

    Dajon,

    Our most of the recent reference design has been with LP87524JRNFRQ1 PMIC. 

    In this reference design, it uses no LDOs, and with this we were able to achieve similar results as that LP87524BRNFRQ1 + 2 LDOs. 

    LDOs offers noise and DCDC ripple filtering. Similar filtering is achieved with the help of LC filters using  LP87524JRNFRQ1 PMIC device. Also this offers lower BOM and lower power dissipation on the board without LDOs. 

    More details on this you could find in the below app-note.

    https://www.ti.com/lit/an/swra577a/swra577a.pdf

    Thanks and regards,

    CHETHAN KUMAR Y.B.

  • 0 in reply to CHETHAN KUMAR Y.B.
    TI__Expert 6861 points

    Hey Chethan,

    Thank you for the answer and collateral. I have a few follow-up questions.

    • Just to verify, having the J part with no LDO won't affect 60GHz RF performance on 1 antenna?
    • Do we have a guide that mentions using 1 antenna vs 3?
    • Lastly, is the LC filter necessary to ensure a clean and stable 60GHz RF signal?

    Best,
    Dajon McGill

  • 0 in reply to Dajon McGill
    TI__Mastermind 25835 points

    Hello Dajon,

      

    Please find my comment below

    • Just to verify, having the J part with no LDO won't affect 60GHz RF performance on 1 antenna?
    • Do we have a guide that mentions using 1 antenna vs 3?

    >>  J part with no LDO and with the LDO there is some difference in the RF performance, In the above collateral this comparison is provided. In nut shell J part without the LDO results are comparable. It would be independent of whether 1 antenna used or 3 antenna used, As long as power supply specs are met it would be fine. 

    • Lastly, is the LC filter necessary to ensure a clean and stable 60GHz RF signal

    >> Yes, LC filters are necessary otherwise it would be very hard to meet the ripple spec on the supply lines. LC filters reduces the DCDC rails residual ripples to acceptable levels.  

    Thanks and regards,

    CHETHAN KUMAR Y.B.