This is an open-source KiCAD design files for a four-channel isolated USB-to-Serial adapter based on CH344Q IC from WCH.
This adapter is convenient when you want to connect multiple serial devices to your computer simultaneously, while also provides isolation between your computer and those devices.
- Four USB-to-Serial channels
- CH344Q IC: Only one USB required to communicate with all fours channels at the same time at maximum speed of 6Mbps.
- 1024 bytes of RX FIFO buffer and 512 bytes of TX FIFO buffer per channel.
- Configured as 2x RS485, 1x RS232, and 1x 5V UART channels.
- Modem flow control signals for RS232 and UART.
- Auto direction control for RS485.
- RS485 120 Ohms termination resistors (on/off)
- Full Isolation
- All power and data signals are fully isolated between the USB and the serial side.
- ADM2483 dedicated RS485 isolation IC.
- ADM3251 dedicated RS232 isolated IC.
- Digital Isolator ICs for other signals.
- 1W 5V isolated DC/DC converter.
- Other Protection
- TVS diodes on all signals line, including the USB.
- Intuitive Interfaces
- USB Type-C Connector
- Degson 3.5mm terminal blocks for serial channels
- Pin header breakout for modem signals
- RX/TX indicators
- USB connection good indicator
- Power indicators on both side of the isolation
- USB reset and flow control mode buttons
- Design to fit a Futurebox FB17 project box
We are currently at Revision 1. Changelog is below:
Revision 1 (November 2022)
- Initial Design
- U9 has wrong footprint (could still be soldered with some difficulties)
The goal of this repository is to enable you to build this on your own as easy as possible. The schematics, PCB design, and an interactive BOM is provided.
Hardware is licensed under SPDX-License-Identifier: CERN-OHL-S-2.0
Contains no software
Documentation is licensed under SPDX-License-Identifier: CC-BY-SA-4.0
You can export gerbers from this project and order the board yourself. You can also use the link below to directly order from Aisler.