This PCB is an implementation of four independent nMOS based bi-directional level shifters. The design is based on Sparkfun BOB-12009 and Adafruit #757. The layout is effectively copied from Sparkfun's version, with minor changes for readability and branding, and for a lower price in the very high quantity that we go through.
All designs are based on Phillips AN97055/NXP AN10441. The used MOSFET is a BSS-138. The specific version used on the first production run was LCSC Part C713688 (datasheet)
The released files can be directly uploaded to JLCPCB, as can the assembly data, for large panels to be ordered.
For those in UPenn ESE, the design can be viewed in the University of Pennsylvania (ESE Labs) A365
Otherwise, it can be accessed on the A365 Viewer