this post was submitted on 18 Jul 2023
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I'm curious and am playing around with a new EDA tool and am looking at practicing by designing a PCB which should be roughly 28x26mm footprint (give or take a few mm...).

It should be an LTE cat 4 device, connected by USB type C for the framework laptop and is unlikely to include antennas.

Where I struggle is identifying potential modems to use. The only one even remotely close is the u-blox LARA-L6, which is 24x26mm. What alternatives are there?

I am trying to see what gets sold in these USB dongles but there is little info. The few I have identified seem to make use of the Qualcomm 9207, but its's unclear to me if its a ready chip (which is what the MDM9207 is?) Or if it is an IP core to integrate in one's own chip?

A video I came across seem to indicate it (the MDM version) is tiny:

https://www.youtube.com/watch?v=ToCyUCIoXEM at 2:13

But will probably needadditional things to be integrated and I created an account at Qualcomm but they won't give anything unless I'm certified from a company to be a customer and actually integrate it...

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[โ€“] [email protected] 2 points 1 year ago (1 children)

Sixfab uses the Telit ME910C1-WW chip on some of their USB models and the Quectel EC25-A for others. They are available as M2 form factor inserts, or you can buy just the chip.

[โ€“] TheHobbyist 1 points 1 year ago* (last edited 1 year ago)

Thanks for the input. I had already looked up the EC25 which is based on the same Qualcomm chip and a tad larger than the L6, but am unfamiliar with Sixfab and the telit chip you mentioned. I'll look them up more. Cheers.

Edit: the Telit chip is 28x28mm and is LTE UE Cat-M1 with 1Mbps up/down from what I understand. Does not seem to offer LTE cat 4 speeds.