https://blog.hackster.io/the-tomu-an-arm-microcontroller-that-fits-in-your-usb-port-31f60af97471
This looks interesting. There are a fair number of USB stick computers on the market. the Tomu is different because it id so small it fits entirely inside your computer’s USB port.
The board is based around Silicon Labs “Happy Gecko” EFM32HG309 Arm Cortex-M0+ microcontroller. It was inspired by the YubiKey 4 Nano. The project is entirely open source with the hardware under the CC BY-SA 4.0 with documentation available on GitHub.
2 Comments
Tomi Engdahl says:
A USB-C connector on a flex PCB
Let’s use an ATtiny84A as a structural element!
https://hackaday.io/project/183302-a-usb-c-connector-on-a-flex-pcb
Tomi Engdahl says:
Genius Or Cursed, This USB-C Connector Is Flexible
https://hackaday.com/2022/01/01/genius-or-cursed-this-usb-c-connector-is-flexible/
USB connectors have lent themselves to creative interpretations of their mechanical specifications ever since the first experimenter made a PCB fit into a USB-A socket. The USB-C standard with its smaller connector has so far mostly escaped this trend, though this might be about to change thanks to the work of [Sam Ettinger]. His own description of his USB-C connector using a flexible PCB and a BGA-packaged ATTiny84A microcontroller is “cursed”, but we can’t decide whether or not it should also be called “genius”.
Key to this inspired piece of connector fabrication is the realization that the thickness of BGA and flex PCB together comes to the required 0.7 mm. The BGA provides the necessary stiffness, and though it’s a one-sided connector it fits the space perfectly. There are several demo boards as proofs-of-concept, and the whole lot can be found in a GitHub repository.
A USB-C connector on a flex PCB
Let’s use an ATtiny84A as a structural element!
https://hackaday.io/project/183302-a-usb-c-connector-on-a-flex-pcb
https://github.com/settinger/USB-C_PCB_experiments