CH340C

The CH340 chip can support RS232, RS485, RS422, and other interfaces through the use of external level conversion devices .

Some features of the CH340 chip mentioned in the document include: - It is a USB bus conversion chip that can convert USB to serial port or USB to printer port. - It provides common MODEM contact signals for expanding asynchronous serial ports on computers or upgrading ordinary serial port devices directly to the USB bus. - It is a full-speed USB device interface that is compatible with USB V2.0. - It emulates a standard serial port for upgrading original serial peripheral devices or adding additional serial ports via USB. - It is a hardware full-duplex serial port with built-in transmit and receive buffers, supporting communication baud rates from 50bps to 2Mbps. - It supports common MODEM contact signals such as RTS, DTR, DCD, RI, DSR, and CTS. - It can provide RS232, RS485, RS422 interfaces through external level conversion devices. - The CH340R chip supports IrDA SIR infrared communication with baud rates from 2400bps to 115200bps. - It has built-in firmware and is software compatible with CH341, allowing the direct use of CH341's VCP driver. - It supports both 5V and 3.3V power supply voltages. - Some variants like CH340C/N/K/E/X/B have built-in clocks and do not require external crystals. CH340B also has an EEPROM for configuring serial numbers. - It offers various lead-free packages such as SOP-16, SOP-8, SSOP-20, ESSOP-10, and MSOP-10, compatible with RoHS. CH340 chip features are detailed in the document.

The main function of the CH340 chip is to serve as a USB bus conversion chip, enabling USB to serial or USB to printer port conversion. It provides common MODEM contact signals for expanding asynchronous serial ports on computers or upgrading ordinary serial port devices directly to the USB bus.