USB 2.0 multi-functional expansion dock based on CH339F

The CH339 is a 7-port multi-functional USB hub controller chip compliant with the USB 2.0 protocol specification. A single chip integrates a 7-port USB hub, USB 100Mbps Ethernet, USB high-speed SD card reader, USB PD, and USB-to-SPI, USB-to-JTAG, USB-to-UART, and USB-to-I2C interfaces. The CH339's upstream ports support USB 2.0 high-speed and full-speed, while its downstream ports support USB 2.0 high-speed 480Mbps, full-speed 12Mbps, and low-speed 1.5Mbps. It also includes multiple internal direct-access channels such as a USB network adapter, USB high-speed card reader, and USB-to-JTAG. The CH339 supports high-performance concurrent processing in MTT mode, adopts an industrial-grade design, and features a streamlined peripheral system. It can be applied to computer and industrial control motherboards, docking stations, peripherals, embedded systems, and other scenarios.
The above information is copied from the datasheet, highlighting typical applications.
Cost: JLCPCB surface mount resistors and capacitors *5 20, USB female connectors (20+20+80) 17, RJ45 100Mbps connectors 1.2 each, CH213K 0.25*20, CH217K 0.38*20, CH339F 9.5*5 (excluding shipping); totaling approximately 16 per board.
USB 2.0 flash drives test normal.
100Mbps Ethernet port recognition normal.
The current problem seems to be that it cannot expand to 4 USB 2.0 ports! (Cause found).
According to the jumper settings in the datasheet, only one flash drive is recognized. The USB isolation extension mode is selected. The default mode cannot recognize USB devices. I don't know if it's due to insufficient power supply or some other reason; the keyboard and mouse are not recognized either. It may be because when the USB device is hot-plugged on the downstream port, the dynamic load may cause the VBUS and 5V voltages to drop momentarily, which may cause LVR low voltage reset, resulting in the entire HUB disconnecting and reconnecting. I'll see how things go after soldering the electrolytic capacitor and SD card slot on.
I can't slack off right now, I'll investigate the cause when I have time.
Experts are welcome to offer guidance and suggestions.
It's currently renamed to a USB 2.0 isolation module with network port (dogo)
. It's recognized once it's plugged in. The
issue was a sudden drop in power supply voltage, causing the chip to reset upon insertion and preventing recognition. Adding the capacitor later fixed it.
There's an unknown issue on 20240710, still investigating the cause!