Twonkie: Open Source USB-PD Sniff, a USB-PD sniffer based on Google Twinkie

Twonkie is a USB-PD sniffer/injector/receiver based on Google's Twinkie project, redesigned to be mass-produced in one-off batches by the average person. Twinkie is an excellent and fairly low-cost solution, and it's open source so anyone can make it themselves, but unfortunately the Twinkie design uses a six-layer PCB and all BGA/wafer-level parts - both of which are not usually available to the average hobbyist. So the author designed Twonkie, a slightly weirder brother of the Twinkie. It uses a four-layer PCB, which can be made cheaply by many service bureaus such as OSHPark, and it only uses leaded parts for easier soldering (although the main microcontroller can also be selected as a QFN via dual packaging). The most difficult part was probably the passive components, which are all 0402, and the USB-C connector used in an unconventional way, namely misusing the 90° upright connector as a 1.6mm jumper mount (in line with the unstable concept). Supports data monitoring and PD packet injection on CC1, CC2 lines, voltage and current detection on VBUS and VCONN.