AWR2243: 20GHz Wilkinson Power Divider of the LO signal

Hi,

Please give us some time to review this question

We will get back to you by end of next week

thank you

Cesar

Hi,

        IN the 4-Chip EVM, the wilkinson splitter was used to branch out the primary device's 20GHz LO to feed to all the secondary devices. As there were more than one secondary device, the splitter became essential.

The second design which you are referring is not yet released on ti.com, however, in that only one secondary device is cascaded, hence the splitter was not essential from the sourcing perspective.

However, the point to kept in mind, design, SIMs and calculations is that the 20GHz LO signal should be from primary device only and with the amplitude power lying in the range mentioned in datasheet.

Regards

Thanks for your reply!

I know what you mean, but I still have some questions,

1. In the 4-Chip EVM, why you choose Wilkinson Power Divider, if high isolation is not necessary, I think T shaped power divider is also OK.

2. In the second design, LO signal cames from two different ports ( syncout and clkout ),  does the signal can be definitely same?  if the LO cames from one port ( syncout or clkout ),then splitted to two branches, is there any help for signal consistency?

3. AWR2243 datasheet gives the min power limit of LO signal , does it have max limit?

Most welcome!

1. Wilkinson power divider is one of the most commonly used splitters. If you intend to use anyother please have all the SIMs validate it before fab.

2. Yes, it would be same. That is what happens in EVM.

3. Yes, please refer the table notes. Also refer the Sync_IN max power limits too.

Regards

Thanks!

Question 3: Sorry, I can't find the Sync_IN max power limits, if you can, please let me know.

Hi,

 Please see below.

Thank you~

I see, so the Sync_IN power shoulu between -6 and 7 dbm , does there exist a most recommended Sync_IN power? 

HI,

       If you intend to configure for the entire temperature band of operation, then I would recommend to keep it between 3dbm to -6dbm.

Regards

Thanks~

so,what would happen if the Sync_IN power was too high.

Hi,

  From the RF Spec, I see the max output power is 10dBm, and the max input power is 7dBm, so I think the LO design should make the loss greater than 3dB, is that right?