NovaRay I/O emulates ASIC to front-panel applications. The “ASIC” — in this case, the ZNA 43 — delivers signals to a Samtec NovaRay® Flyover® cable assembly, which then travel through 6″ of Eye Speed® Twinax Low Skew twinax, to a NovaRay I/O connector/cable system. This assembly also includes our NovaRay I/O front panel brackets, and exclusively from Samtec, a NovaRay I/O, front-panel DAC.
In this demonstration, the DAC is two meters long, and it returns to another front-panel NovaRay I/O-to-NovaRay cable system, and then back to the Rohde and Schwarz ZNA 43. The ZNA 43 is rated from 10 MHz to 43.5 GHz, with 2 or 4 ports.
When testing a cable system like NovaRay I/O, it’s essential to be able to de-embed the test fixture from the overall results. We obviously don’t want to be measuring the fixture and the test cable ports.
The De-embedding Assistant on the ZNA 43 helps guide the user to create a balanced input and output model for the fixture. We start by selecting a balanced lead-in and a balanced lead-out in the first step of the De-embedding Assistant. The second step provides the two measurements needed for the de-embedding algorithm. The first measurement is our Coupon Measurement, which is a balanced, symmetric, 2X through coupon (a calibration standard).
The second step makes a measurement of the full structure, which is the Samtec cables plus the fixture. From these two measurements, we can extract the cables’ response.
Once we close the De-embedding Assistant we see a full suite of results, including insertion loss. When looking at the results from 0 to 40 GHz, we see a flat insertion loss response, from 0 to -30 dB, across the entire frequency range.
With a Nyquist at 28 GHz, for 112 Gbps PAM4 performance, we have a clean eye diagram across the entire frequency range. The ZNA 43 measures frequency domain, time domain, and eye diagram parameters.
Here’s a link for more information on the Rohde and Schwarz ZNA 43. And of course, here are links to learn more about the NovaRay I/O front-panel system, and NovaRay mid-board cable system. Check out this demo from DesignCon 2021 with a Rohde and Schwarz VNA 67.