• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 30 subscribers
  • Views 668 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.

IWR6843ISK-ODS: About the PCB material of IWR6843ISK-ODS EVM, Ro3003 or Ro4350b?

hui Chen
Intellectual 450 points
Part Number: IWR6843ISK-ODS
Other Parts Discussed in Thread: IWR6843, , IWR1443, IWR6843ISK

I am developing a new project based on IWR6843, I taking the swrc356a (IWR6843ISK-ODS rev.c) as a reference. This design is working at 60GHZ, the PCB material of TI EVM is Ro3003/5mil. I have designed a project based on IWR1443, which worked at 77GHZ, the PCB material of TI EVM is Ro4350b/4mil.

In general, the performance of Ro3003 is better than Ro4350b. so I wonder why does IWR6843ISK-ODS uses the better material but works at a lower frequency?   Are there any special considerations here? 

I have communicated with lots of PCB factory, they said the Ro3003 was not a regular material, if they are required to use Ro3003, they must prepare it for a very long time, but the Ro4350b is regular material for RF PCB.

So I want to use Ro4350b to produce my new IWR6843 based design. I wonder if the dimension of antenna in current EVM IWR6843ISK-ODS rev.c applies to R04350b directly?  If no, how do I re-design the dimension of antenna? Are there some guidelines available?  

  • 0
    TI__Mastermind 25835 points

    Hello Hui Chen,

        IWR1443 EVM is developed with 4mil RO4835LOPRO material. 

    In general we wanted to give design recommendation at 60GHz on Roger3003 (Higher performance at higher cost)  and RO4835LOPRO (Moderate performance as compared to RO3003 but lower cost and ease of fabrication) designs. 

    Hence for IWR6843ISK design uses 4mil RO4835LOPRO material and IWR6843ISK-OD uses 5mil RO3003 based design. 

    RO4350B material is very close to 4mil RO4835LOPRO design, However RO4835LOPRO material is designed for lower losses at mmWave frequencies.

    Dielectric constant is different between RO3003 and RO4350B hence dimensions of the antenna will not work with IWR6843ISK-ODS. Hence you may look at IWR6843ISK design to start with. 

    However TI EVMs are not developed with RO4350B material, hence you have to tweak the design yourself as per your requirements. currently we do not have any guidelines available. 

    Thanks and regards,

    CHETHAN KUMAR Y.B.