With the campaign now having drawn to a close, we’d like to take this opportunity to thank everyone who backed LimeSDR XTRX. When the campaign launched, we promised we’d provide details of some of the many improvements we made to XTRX as part of its transition to the LimeSDR family. So here you go!

Schematic

There were quite a few changes to the schematic, ranging from general optimisations to make the design a bit more intuitive, to adding extra decoupling capacitors and replacing end-of-life and very long lead time components. Some notable improvements include implementing FPGA control of the GNSS receiver power mode and connecting its fix status output to the FPGA.

However, it’s important to note that none of the changes implemented should effect existing functionality and that all connector designators were left unchanged.

Layout

There were similarly quite a few layout changes, but again none which should affect existing functionality. Improvements include a more informative silkscreen, reduced number of vias and routing layers, and making L5 a ground plane, with L6 now isolated from both sides. Also, we reduced the number of layer changes in RF routing. We also made some footprint changes for wider device compatibility, which should help reduce potential future component sourcing issues.

Gateware

By far the biggest change from a user perspective is a complete rewrite of the FPGA gateware, enabling XTRX to become a full-fledged member of the LimeSDR family, fully supported by the Lime Suite driver stack and APIs, alongside existing boards. This should greatly increase compatibility with existing applications which already support LMS API.

The Fairwaves gateware and driver will both remain available for use with applications that require them, but they will no longer be developed or supported, so we recommend migrating to the new gateware and Lime Suite in order to receive updates and support.

Stay Tuned

We’ll be providing updates between now and when boards ship at the end of November, so keep a look out as we share details of how to get up and running with LimeSDR XTRX, demos, and manufacturing updates!