CC2642R: s-parameter file

Hi Adhithiya,

I am currently checking the availability of the s-parameter file with my team. I will follow-up with your request as soon as possible.

Best regards,

Bun

Hi Adhithiya,

Unfortunately, we do not have any s-parameter files available. However, in section 9 of the swra640 (see picture below) you will find the impedance we match to in order to achieve 50 ohms at the output of the balun. Alternatively, you can refer to our reference design here: https://www.ti.com/lit/zip/SWRC359, assume a 50 ohm match at the balun output, and work backwards to achieve the impedance of the device.

Best regards,

Bun

We are using LFB182G45BG5D920 in combination with CC2642R. What should be the impedance of the differential transmission lines that connects the balanced ports of the balun to the BLE IC? Can you share some rough calculation for this test case or some example calculation?

Assuming you are using the internal biasing, the output of the IC would roughly be 42 +J21 ohm so you would have to match to the conjugate of this. However, the balun BPF you listed is already matched to our cc26xx devices (differential or single-ended) so there is no need for any matching circuits.

Bun

It means that we can differential transmission lines from CC2642R and LFB182G45BG5D920 with the following impedance specs?

1. 50 ohm lines with reference to ground 

2. impedance between the differential lines of 100 ohms

Correct, the LFB182G45BG5D920  can be used in single-ended or differential configuration with no matching circuit needed with the CC2642R device.

Bun