> For the complete documentation index, see [llms.txt](https://jordan-cormack.gitbook.io/stuff/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://jordan-cormack.gitbook.io/stuff/pcbs/m2-usb.md).

# M.2 Cellular Adapter

A breakout board for laptop style M.2 cellular modules, intended to be used in UAVs or similar systems.

## Latest Version (V2)

<mark style="color:red;">Warning!</mark> Ensure bolt heads have sufficient clearance to bottom of installed M.2 module. Standard socket head cap screws **do not fit** in the two lower bolt holes. Use low profile or button head fasteners.

<figure><img src="/files/kRqUrAqz5llBNUmX54m6" alt=""><figcaption></figcaption></figure>

Features:

* Tested with [AirPrime EM7455](https://source.sierrawireless.com/devices/em-series/em7455/) and [Telit LE910Cx](https://techship.com/product/techship-le910c4-wwxd-lte-cat-4-m2/?variant=002) based LTE modules (others may be compatible)
* USB 2.0 connectivity through either:
  * USB-C
  * JST-GH
* Dual physical SIM (only single SIM1 tested so far)
* 30.5mm x 30.5mm M3 mounting holes
* at least 60 Mbps download and 25mbps upload tested

Note: Default SIM detect configuration is SIM1 'open' and SIM2 'closed' (bridged jumper). Depending on the LTE module, the expected SIM detect state may be inverted.

### To do:

* Test SIM slot 2 functionality
* Add USB breakout pads
* Add USB 3.0 support
* SIM detects
* Add diode (maybe LM66200) to separate USB and JST-GH 5V inputs.

## Version History

### V2

Latest version.

### V1

Initial version. Mostly the same as V2 but longer form factor, with a single SIM slot and pads instead of JST-GH connector.