Simple adapter to install up to 2 dual Coral TPU modules in m.2 E key format to m.2 M key 2280 nvme slot. Single E key Coral modules and a combination of single and dual ones should work as well. The idea was to create a simple and affordable adapter on a two-layer PCB that can be soldered without any special equipment and professional soldering skills. The drawback is that it relies on some specific hardware and components, but they are still relatively easy to purchase. Also, it goes out of m.2 2280 slot dimensions by 8 mm on the side of the secure screw.

The main part is m.2 M key expansion board based on the ASM1184E chip. It splits 1 PCIE lane into 4 single ones. It affects the speed, but for this specific application, the PCIE speed affects only a little. The adapter is connected to this board with 4 USB-3 Type A male connectors. The adapter has its power supply and needs an external power source of 5-12V. The adapter's PCB is installed above the expansion board as a sandwich, having an overall height of about 25 mm without Coral heat sink. The dimensions allow installation into the Dell Micro 50XX/70XX case, but without a heatsink, so it may have issues with heat dissipation there. The author used a Chatreey iT12 mini-pc which is available on Aliexpress without its bottom cover. The adapter hangs over m.2 2280 secure screw by around 8 mm. But in most cases, it should not be an issue.

See the detailed description in the GitHub repo