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CH340

USB to serial chip

The CH340 is a usb to serial chip from Eaton Electrical. View the full CH340 datasheet below including key specifications.

Official CH340 datasheet (PDF) — the source this page was extracted from.

Manufacturer

Eaton Electrical

Category

USB to serial chip

Package

SOP-16, SSOP-20, MSOP-10

CH340 Key Specifications

ParameterValue
Standard Pack Qty1
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)

CH340 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

CH340 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.

Variants on the same datasheet

These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.

Part NumberManufacturerPackage
CH340GWCHSOP-16

More part numbers on this datasheet

Their pages show this same datasheet. Some are linked through their part family rather than checked part by part, so confirm the exact part in the ordering information.

Data on this page is extracted from publicly available manufacturer datasheets using automated tools including AI. It may contain errors or omissions. Always verify specifications against the official manufacturer datasheet before making design or purchasing decisions. See our Terms of Service. Rights holders can submit a takedown request.

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Then ask: "Can the CH340 run from my 12 V rail? Check it against the datasheet limits."

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