We recently caught up with Dan Birch, global RF engineering manager at Samtec, who showed us the company's latest addition to its Bulls Eye lineup of high-performance test assemblies: the BE90A. It provides usable bandwidth out to 90 GHz.
Such assemblies are critical to accurate characterizations of the serial/deserializer (SerDes) interfaces found in extremely high-speed communication links. The Bulls Eye test assemblies feature a high-density, space-saving design that enables smaller evaluation boards and shorter trace lengths in test and measurement applications (Fig. 1).
The Bulls Eye block mounts to the board directly adjacent to the SerDes being characterized. Its solderless design improves overall cost and is easy to use within a lab setting. End 2 of the cable assembly connects to instrumentation using any of the following connector options: 1.00, 1.85, 2.40, or 2.92 mm.
For near-perfect fidelity for 224-Gb/s PAM4 SerDes characterization, the new BE90A is the assembly of choice. However, as shown in Samtec’s live 224-Gb/s PAM4 demonstration, the 70-GHz BE70A assembly is also capable of handling 224-Gb/s PAM4 when taking certain signal-integrity optimizations into consideration.
These high-speed interfaces have become so prevalent that the need for multichannel, high-speed, compression-mount connectors with very high signal integrity has steadily grown. Samtec’s Bulls Eye assemblies have been adopted for use in clock/data recovery (CDR) for communications, mmWave radar systems, automated test equipment, next-generation FR2 5G networks, and a variety of custom high-density high-performance designs. Single-row options are also now available, supporting smaller board real estate in emerging high-performance, high-density applications.
Here's a transcript of the video (it has been edited for clarity):What we're demonstrating here is the latest in our Bulls Eye test connector system. This is a compression-mount test connector system that allows our customers to make a lot of high-speed connections very quickly on a very-small-area printed circuit board.
The latest generation here is BE90A and the system's got 90 GHz of usable bandwidth. So we have a signal source on the VNA coming in with a 1-mm connector and cable, and that's coming in to this cable on the Bulls Eye 90 system.
A 0.47-mm cable comes into the Bulls Eye connector, goes through about 2 inches of micro strip, and out through a 1.35-mm test port or a vertical launch connector and back to the VNA. We've de-embedded that and the net result is we've got just more than 5 dB of insertion loss all the way out to 90 GHz and almost 15 dB of return loss (Fig. 2) . So, as I mentioned earlier, there's a lot of usable bandwidth here with the system and that's what we're shooting for. So if you have any more questions, feel free to go to our website for more information.