XB3-24Z8xx can I interchange RM - CM - UM modules without degradation to signal?

I have a PCB designed to host an XB3-24Z8RM with RF pad to SMA via PCB. The PCB was designed with all considerations from page 37 of the XB3 Hardware Reference Manual for RF Pad design

Due to the recent shortage and distant restock of these devices, I’d like to swap for similar modules with different antenna designs. Particularly, XB3-24Z8UM or XB3-24Z8CM are identical with the exception of the antenna design/placement. I would still use pin 36 to my PCB RF pad antenna, but I’m worried the UM or CM models have internal antenna connections that could interfere and degrade signal performance if I attempt to use them with an RF pad.

Please advice.


You can’t swap out the different antenna options and still use the RF pad lines as they are not connected on the different options. What you can do is use the different firmware options instead. That is, purchase the Digi Mesh or 802.15.4 versions and then change the firmware to the desired version and function set.

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Thanks for the help. After blasting the forum with this question and arrived and the same result through tech support as well.

The real issue with various antenna designs is that pin 36 is disabled on boards not meant for the RF pad antenna.

Furthermore, PCB design restrictions are very different for the RF pad antenna vs. other versions built into the radio module itself.

My solution is as you mentioned, purchase other software versions and migrate the firmware to what I need.