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CH340G

USB to serial chip

The CH340G is a usb to serial chip from WCH. View the full CH340G datasheet below including pinout.

Manufacturer

WCH

Category

USB to serial chip

Package

SOP-16, SSOP-20

Overview

Part: WCH CH340

Type: USB to Serial Converter

Description: USB V2.0 compatible device interface that emulates a standard UART, supporting baud rates from 50bps to 2Mbps, with variants offering built-in crystal and EEPROM for configuration.

Operating Conditions:

  • Supply voltage: 2.8–5.3 V
  • Operating temperature: -40 to +85 °C
  • UART baud rate: 50bps to 2Mbps
  • Input clock frequency: 11.98–12.02 MHz (for variants requiring external crystal)

Absolute Maximum Ratings:

  • Max supply voltage: 6.0 V
  • Max continuous current: null
  • Max junction/storage temperature: 125 °C

Key Specs:

  • Operating Supply Current (CH340G/C/E/T/R, Normal Operation): 7 mA (Typ), 20 mA (Max)
  • Operating Supply Current (CH340B, Normal Operation): 6 mA (Typ), 15 mA (Max)
  • Suspend Supply Current (VCC=5V): 0.1 mA (Typ), 0.2 mA (Max)
  • Low-level Input Voltage (VIL): -0.5 V (Min), 0.7 V (Max)
  • High-level Input Voltage (VIH): 2.0 V (Min), VCC+0.5 V (Max)
  • Low-level Output Voltage (VOL, 4mA draw current): 0.5 V (Max)
  • High-level Output Voltage (VOH, 3mA output current): VCC-0.5 V (Min)

Features:

  • Full speed USB device interface, compatible with USB V2.0.
  • Emulates standard UART interface, supports 50bps to 2Mbps baud rate.
  • Supports common MODEM liaison signals (RTS, DTR, DCD, RI, DSR, CTS).
  • Supports 5V, 3.3V, and 3V power supply.
  • CH340C, CH340E, CH340B have built-in crystal, no external crystal required.
  • CH340B integrates EEPROM for configuring serial number and other information.
  • CH340R supports IrDA criterion SIR infrared communication.

Applications:

  • USB to RS232 Converter
  • USB to TTL Converter
  • USB to Infrared Adapter
  • USB to RS485 Converter

Package:

  • SOP-16
  • MSOP-10
  • SSOP-20

Features

  • Full speed USB device interface, compatible with USB V2.0.
  • Emulate standard UART interface, used to upgrade the serial peripherals, or expand UART interface via USB bus.
  • Original serial applications are totally compatible, without any modification in Windows operation system.
  • Hardware full duplex serial UART interface, built-in transmit-receive buffer, supports communication baud rate varies from 50bps to 2Mbps.
  • Supports common MODEM liaison signal RTS, DTR, DCD, RI, DSR and CTS.
  • Through external level conversion chip provide further RS232, RS485, RS422 interface, etc.
  • CH340R supports IrDA criterion SIR infrared communication, supports baud rate varies from 2400bps to 115200bps.
  • Software compatible with CH341, use driver of CH341 directly.
  • Support 5V and 3.3V power supply even 3V.
  • CH340C, CH340E and CH340B have built-in crystal, no external crystal, CH340B also integrates EEPROM used to configure the serial number, etc.
  • SOP-16 and SSOP-20 and MSOP-10 lead-free RoHS compliant package.

Pin Configuration

PinNameTypeDescription
1GNDPOWERPublic ground, ground connection for USB
2TXDOUTTransmit asynchronous data output(reverse output for CH340R)
3RXDINReceive asynchronous data input, built-in configurable pull-up and pull-down resistor
4V3POWERConnect toVCC to input external power when 3.3V power supply, connect to 0.1μF decoupling capacitor when 5V power supply
5UD+USB signalDirectly connect to D+ data wire of USB bus
6UD-USB signalDirectly connect to D- data wire of USB bus
7XIINCH340T/R/G: Input of crystal oscillator, connect to crystal and capacitor
8XOOUTCH340T/R/G: Output of crystal oscillator, connect to crystal and capacitor
9CTS#INMODEMliaison input signal, clear to send, active low(high)
10DSR#INMODEMliaison input signal, data set ready, active low(high)
11RI#INMODEMliaison input signal, ring indicator , active low(high)
12DCD#INMODEMliaison input signal, data carrier detect, active low(high)
13DTR#OUTMODEMliaison output signal, data terminal ready, active low(high)
14RTS#OUTMODEM liaison output signal, request to send, active low(high)
15R232INCH340T/R/G/C: Assistant RS232 enable, active high, built-in pull-down resistor
16VCCPOWERPositive power input port, requires an external 0.1μF power decoupling capacitor

Related Variants

The following components are covered by the same datasheet.

Part NumberManufacturerPackage
CH340WCHSOP-16
CH340BWCHSOP-16
CH340CWCHSOP-16
CH340C/BWCH
CH340C/E/BWCH
CH340DS2WCH
CH340EWCHMSOP-10
CH340G/C/B/TWCH
CH340G/C/E/TWCH
CH340G/C/T/RWCH
CH340G/T/RWCH
CH340HWCH
CH340H/SWCH
CH340NWCHSOP-8
CH340RWCH
CH340TWCHSSOP-20-209mil
CH340T/E/BWCH
CH340T/R/GWCH
CH340T/R/G/CWCH
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