The Rock 5B RK3588 multiplexes a single USB-C PD port for both power and USB data. For frequent firmware flashing, connecting this port directly to a host is convenient because it directly provides access to MaskROM mode to flash opencca firmware.
Many hosts cannot supply enough current for the board to operate reliably under high load.
This repository provides a custom PCB that de-multiplexes the USB-C PD connection back into
- USB 2.0 data line for flashing
- and a dedicated power input for external power supply.
src contains a KiCad project with the board's schematic and a PCB layout.
src/gen contains pre-generated Gerber and Drill files for printing.
Each board requires these parts:
- 3x GCT USB4105-GF-A: USB-C receptacle, USB 2.0 (16-pin), top-mount horizontal, TH shield legs (Footprint:
Connector_USB:USB_C_Receptacle_GCT_USB4105-xx-A_16P_TopMnt_Horizontal) AliExpress - 2x 5.1kΩ resistor, 0805 (2012 metric), ±1% (Footprint:
Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder) AliExpress
Optionally the board contains 3 mounting holes for 3.2mm M3 screws.
The circuit topology of this board is based on a schematic provided by CentyLab (web archive). It was used as a functional reference only, all schematic and PCB files were drawn independently in KiCad.