u-blox Migration Path to Crystal-Based Solutions

On October 20, 2020, Asahi Kasei reported a fire in one of their foundries in Nobeoka, Myazaki Prefecture, Japan. This was a force majeure event. Asahi Kasei is a chip supplier for several of our TCXO suppliers. Since AKM is providing about 80% of the world market with oscillators, including several TCXO manufacturers that supply u-blox some of their components, u-blox has been working tirelessly to find different solutions to different products affected by this crisis. One such effort has been the recognition of equivalent product using alternative approaches.

u-blox offers great products that are crystal-based rather than TCXO solutions. The crystal-based options have the same footprint as their correlating TCXO counterpart. The parts do have some minor functional performance differences, but u-blox has outlined these changes in their app notes, which can be viewed at the following links: EVA-M8 TCXO-to-crystal migration guide MAX TCXO-to-crystal migration guide, CAM-TCXO-to-Crystal-Migration-Guide, and NEO TCXO-to-crystal migration guide. The most notable difference is crystal-based receivers need to search over a wider range of frequencies which extends the Time-To-First-Fix (TTFF), especially in weak signal conditions. With proper adjustments and design guidelines, crystal-based u-blox GNSS receivers can achieve very similar performance to a TCXO-based solution.

See the below chart for part number conversions from TCXO to crystal-based.

TCXO Part Number Crystal Alternate Option 1 Crystal Alternate Option 2
MAX-M8Q-0 MAX-M8C-0  
MAX-8Q-0 MAX-8C-0 MAX-M8C-0
NEO-8Q-0 NEO-M8J-0 NEO-M8M-0
EVA-M8Q-0 EVA-M8M-0  
CAM-M8Q-0 CAM-M8C-0  
MAX-7Q-0 MAX-7C-0 MAX-8C-0
NEO-7N-0 NEO-7M-0 NEO-M8M-0
NEO-6G-0 NEO-7M-0 NEO-M8M-0
NEO-6Q-0 NEO-7M-0 NEO-M8M-0