I am happy to say that I’m finally done with the hardware design of the URU Key device.

It took a few months and number of iterations to complete it but now I have the device I wanted to have.

The size of the PCB is only 40x15mm, it’s comparable to a regular fitness tracker.

Main features are:

• ESP32 Pico D4 system on a chip. Two cores, up to 240MHz, 4Mb of flash memory.
• ATECC508A security co-processor. The complete solution for the cryptographic algorithms and key management.
• FPC1020AP capacitive fingerprint scanner.
• Rechargeable LiPol battery and USB Type C for charging.

I understand that I’m not a hardware engineer and the design, probably, has a lot of mistakes. But for hobbyist, it is definitely good. It definitely solves the problem I wanted to solve - to create small wearable authenticator device with the biometric scanner and wireless connection.

The remaining challenges have to be solved on the software side where I am a bit more experienced than in hardware. That means it will be more of a just work than research and I can say I am very optimistic about the result of the project now.

Oh, and case. The device needs case.