4-port USB 2.0 expansion dock design based on CH334U

I. Appearance
First, let's talk about the appearance.
 
This project uses a 1.5mm thick transparent acrylic panel as the docking station's outer shell. White or black is recommended for the panel color, as it matches the panel's pattern. (White panels are prone to soldering smudges; black is recommended if cleaning the panel is inconvenient.)
The entire unit is very compact, fitting perfectly in the hand.
 
It uses a Type-C female port for upstream connection. Compared to traditional docking stations, it doesn't require external data cables, allowing for plug-and-play functionality and significantly improving portability.
 
Here are a few more images of the exterior.
 
II. Functionality of this Project
1. A 4-port USB 2.0 docking station design based on CH334U and CH217K chips. CH334U acts as the HUB chip, expanding the USB 2.0 interfaces, while CH217K acts as an overcurrent detection chip, monitoring the current in real time. 1. Ensures safety by checking if the current exceeds the threshold.
2. A master switch for one-button control of all USB ports.
3. A status indicator light that illuminates when a communication interface is connected to a USB port and turns off when there is no communication connection.
 
III. Hardware Circuit Assembly:
The hardware circuit for this project is designed based on the overall overcurrent detection application of the CH334/CH335 datasheet. The CH217K is used as the overcurrent detection chip. When the current is too high, the CH217K pulls the OVCUR# pin of the CH334U low to tell the CH334U that there is an overcurrent and stops working.
1. The core circuit is shown in the figure below, using a 12MHz crystal oscillator as the clock.
 
2. The downstream port circuit is shown in the figure below. Each port is equipped with a 100uF capacitor to ensure power supply stability.
 
3. The overcurrent detection circuit is shown in the figure below, limiting the current Iset = 60kJ/R6 = 2A.
 
4. The status indicator circuit is shown in the figure below. A lit indicator indicates normal operation (Active), while an off indicator indicates the HUB chip
is in sleep mode (Suspend). The "normal operation" indicator is interesting; it means there is data communication. The indicator light will only light up when there is normal data communication. If it is only used as a power supply port, it will not light up.
 
5. The input interface is shown in the figure below.
It uses a TYPE-C interface, which can be plugged in either way. It only requires a TYPE-C data cable to function. It also features a master switch, transient suppression diodes, and a resettable fuse, maximizing safety.
 
IV. Physical Display
 
V. Installation Details:
The screws I bought were too short; I found a longer one and shortened it before installation. I won't post the specifications now; I'll update them when the new parts arrive (if anyone wants to replicate this).
 
VI. Precautions:
1. This project does not involve software development.
2. Although this project has an acrylic casing for protection, the circuitry is still exposed. Please be extremely careful with electricity and avoid liquid spills.
3. For the uplink port connection, please use a data cable that supports data communication. Some data cables only support power connection and cannot achieve data communication.