Several models of WCH systems from the CH3 series

We offer several models of WCH systems from the CH3 series.

CH315G is a chip used as a USB bus expander. It provides both speeds of the standard USB port version 2.0 (Low-speed and Full-speed), adjustment of the operating mode (downstream or upstream), as well as compatibility with the plug & play standard. The maximum distance that can be achieved using the mentioned system is 300m in Low-speed mode and 75m in Full-speed mode.

CH315H is, in turn, a system that allows the coupling with the bus of isolating circuits. It supports, among other things, a very cheap 6N137 optocoupler from Fairchild, which is also available in our offer. At the same time, the CH315H chip provides support for both speeds of the USB 2.0 standard, two operating modes (downstream and upstream) it also provides built- in activity indicator pin which can be connected to an external LED.

The remaining CH330N and CH340 chips in versions B, C, E, G and T are USB to UART converters. They can be used to connect interfaces of devices such as microcontrollers, printers, electronic meters and all other devices using the UART serial transmission standards as well as RS232 and RS485 after additional conversion of logical levels through the USB serial port. In addition, the CH340C / E / B models do not require an external quartz resonator, as does the CH330N. The CH340C / B / G / T models provide additional modem inputs to be used when working on the USB bus, and the CH340T model has an additional output to which the signal from the internal clock is led, and an input pin to control the sleep function and an output pin indicating the completion of USB port configuration transfer.

A useful function may also be the programmable EEPROM memory attached to the CH340B model, where you can save the serial data of the device on which the system is used. All converter models provide interface speeds between 50bps and 2Mbps.

All of the systems are capable of operating at voltage levels of both 5V and 3.3V which makes them suitable choice in a vast majority of the applications.