Hi all,
I am trying to identify a MMCX connector 75 vs 50Ω. I am aware the pin section is different to fit the impedance matching, but looks like the connector shape itself is also different? I have this pair. See picture below:
Many thanks in advance!
Hello jordi,
Welcome to the DigiKey TechForum community.
I’m not sure if there is a standard that these can be recognized against and I could not verify the difference between them visually in your photo. There is not a lot to go by here except to compare the data sheets of each connector style. For example, SAMtec provides some pictures on their website of the MMCX connectors here: MMCX RF Cable Assemblies & Connectors, 50 Ohm & 75 Ohm | Samtec
I don’t see a whole lot of difference from that link between the 50 ohm cable terminated one and 75 ohm cable terminated ones.
Our options of MMCX connectors and cables in 75ohm and 50ohm are in below link.
You might be able to find something there that can help you identify which cable connection you have. In general, from what I understand, a 50ohm cable should not be connected to a 75ohm connector and vice versa. If you know you have a 75ohm cable there, then it’s probable that those connectors are also 75ohm.
Thank you so much for your answer.
just note the mmcx outline shape is quite different. I have been checking many products in your website regarding the MMCX connectors, and then, checking the pictures/3D from manufacturers website. And looks like the MMCX 75 or 50ohm are a bit differents. See the screenshot from Samtech 3D cad files. Both connectors are MMCX, but the connector shape is not the excatly the same.
Many thanks in advance!
Hi jordi,
A “standard” MMCX connector is, by definition, a 50Ω part. Only your diagram on the right is a standard MMCX connector. They do not come in a 75Ω option.
Samtech makes a couple connector series that they call “high-vibration” versions of “MMCX” connectors, but they look different and are not compatible with standard MMCX connectors. They make them in both 50Ω and 75Ω, so the different form-factors you noted are not related to impedance, but rather they are a different type of connector altogether. You can find these and standard MMCX series products from them listed on the Samtech website here.
This TechForum post covers more about the 50Ω version.
So, when searching our website for MMCX connectors, make note of the “Connector Style” and select either the standard “MMCX” products or the Samtech-unique MMCX (V) series, as shown below:
Footnote: At the time of this writing, the 75Ω MMCX7 series parts are listed as being “Connector Style” of “MMCX” rather than “MMCX7”. This should be corrected shortly.
