USB to 4-way ttl serial port

Sometimes for testing, you need to connect several serial ports at the same time, which takes up a lot of the USB port of the computer. Even using USBhub is relatively cumbersome. In view of this, we specially designed the USB to 4-channel ttl serial port test of the USBHUB chip HS8836A + 4-channel CH340N. module. The input uses USB type B interface. Firstly, it is sturdy. Secondly, I have a lot of B port cables that I can’t use hahaha~~~

The input has a self-restoring fuse to prevent overload, 1117 to 3.3 voltage stabilization, supports 5V and 3.3V output, and can be used for external power supply. The jumper cap allows CH340 to be connected to a 5V or 3.3V power supply.

There are two switches in front of the serial port output. One is to cut off the RX and TX of the serial port, which is equivalent to unplugging the serial port cable. The other is to interchange RX and TX. This function is redundant but practical. If you plug in reverse wires, you only need to press the switch. , you can change it~~~