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CH340K

The CH340K is an electronic component from WCH. View the full CH340K datasheet below including absolute maximum ratings.

Manufacturer

WCH

Overview

Part: CH340 — WCH Type: USB to Serial Port Adapter Description: The CH340 is a USB bus adapter chip that provides a full-speed USB device interface compatible with USB V2.0, emulating a standard serial port with communication baud rates from 50bps to 2Mbps, and supporting 5V or 3.3V power supply voltages.

Operating Conditions:

  • Supply voltage: 3.1–5.3 V (for 5V operation: 4.0–5.3 V; for 3.3V operation: 3.1–3.6 V)
  • Operating temperature: -40 to 85 °C (for CH340G/T/R); -20 to 70 °C (for CH340C/N/K/E/X/B)
  • Communication baud rate: 50bps – 2Mbps

Absolute Maximum Ratings:

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

Key Specs:

  • Operating supply current (5V, CH340G/C/N/K/E/X/T/R): 7 mA (typ), 20 mA (max)
  • Operating supply current (3.3V, CH340G/C/N/K/E/X/T/R): 4 mA (typ), 12 mA (max)
  • USB Suspend current (5V, CH340C/N/E/X): 0.05 mA (typ), 0.15 mA (max)
  • Low-level input voltage (5V): 0.9 V (max)
  • High-level input voltage (5V): 2.3 V (min)
  • Low-level output voltage (5V, 6mA sink): 0.5 V (max)
  • High-level output voltage (5V, 2mA source): VCC-0.6 V (min)
  • Power-on reset voltage threshold: 2.4 V (min), 2.6 V (typ), 2.8 V (max)

Features:

  • Full-speed USB device interface, compatible with USB V2.0.
  • Emulates standard serial port, compatible with Windows serial port applications.
  • Hardware full-duplex serial port, built-in transceiver buffer.
  • Supports common MODEM handshake signals: RTS, DTR, DCD, RI, DSR, CTS.
  • Provides RS232, RS485, RS422 interfaces through external level conversion.
  • CH340R supports IrDA specification SIR infrared communication.
  • Supports 5V and 3.3V power supply voltages.
  • CH340C/N/K/E/X/B have built-in clock, no external crystal oscillator required.
  • CH340B has built-in EEPROM for configuring serial numbers.

Applications:

  • Upgrading original serial peripheral devices to USB.
  • Adding extra serial ports to computers via USB.
  • Multi-mode MCU download.
  • SIR infrared communication (CH340R).

Package:

  • SOP-16
  • SOP-8
  • ESSOP-10
  • MSOP-10
  • SSOP-20

Features

  • Full-speed USB device interface, compatible with USB V2.0.
  • Emulates standard serial port, used for upgrading original serial peripheral devices, or adding extra serial ports via USB.
  • Serial port applications under Windows operating system on the computer side are fully compatible, no modification required.
  • Hardware full-duplex serial port, built-in transceiver buffer, supports communication baud rate 50bps ~ 2Mbps.
  • Supports common MODEM handshake signals RTS, DTR, DCD, RI, DSR, CTS.
  • Provides RS232, RS485, RS422 and other interfaces through external level conversion devices.
  • CH340R chip supports IrDA specification SIR infrared communication, supports baud rates from 2400bps to 115200bps.
  • Built-in firmware, software compatible with CH341, can directly use CH341's VCP driver.
  • Supports 5V power supply voltage and 3.3V power supply voltage.
  • CH340C/N/K/E/X/B have built-in clock, no external crystal oscillator required, CH340B also has built-in EEPROM for configuring serial numbers, etc.
  • Provides SOP-16, SOP-8 and SSOP-20 as well as ESSOP-10, MSOP-10 lead-free packages, RoHS compliant.

Absolute Maximum Ratings

NameParameter DescriptionParameter DescriptionMinMaxUnit
TAOperatingCH340G/T/R-4085°C
TAAmbient TemperatureCH340C/N/K/E/X/B-2070°C
TSStorage Ambient TemperatureStorage Ambient Temperature-55125°C
VCCPower Supply Voltage(VCC connected to power, GND connected to ground)-0.56.0V
VIOVoltage on Input or Output PinVoltage on Input or Output Pin-0.5VCC+0.5V
  • 6.2. 5V Electrical Parameters (Test conditions: TA=25 °C, VCC=5V, excluding pins connected to USB bus)
  • 6.3. 3.3V Electrical Parameters (Test conditions: TA=25 °C, VCC=V3=3.3V, excluding pins connected to USB bus)
NameParameter DescriptionParameter DescriptionMinTypMaxUnit
VCCPower Supply VoltageV3 pin only external capacitor, not connected to VCC4.055.3V
ICCOperating CH340G/C/N/K/E/X/T/ROperating CH340G/C/N/K/E/X/T/R720mA
ICCTotal Supply Current CH340BTotal Supply Current CH340B615mA
ISLPUSB Suspend CH340G/K/T/R/BUSB Suspend CH340G/K/T/R/B0.090.2mA
ISLPTotal Supply Current CH340C/N/E/XTotal Supply Current CH340C/N/E/X0.050.15mA
VILLow-Level Input VoltageLow-Level Input Voltage00.9V
VIHHigh-Level Input VoltageHigh-Level Input Voltage2.3VCCV
VOLLow-Level Output Voltage (6mA sink current)Low-Level Output Voltage (6mA sink current)0.5V
VOHHigh-Level Output Voltage (2mA source current) (Chip reset period only 100μA source current)High-Level Output Voltage (2mA source current) (Chip reset period only 100μA source current)VCC-0.6V
IUPInput Current of Input Pin with Built-in Pull-up ResistorInput Current of Input Pin with Built-in Pull-up Resistor3150300μA
IDNInput Current of Input Pin with Built-in Pull-down ResistorInput Current of Input Pin with Built-in Pull-down Resistor-40-100-300μA
VRPower-on Reset Voltage ThresholdPower-on Reset Voltage Threshold2.42.62.8V
NameParameter DescriptionParameter DescriptionParameter DescriptionMinTypMaxUnit
VCCPower Supply V3 Pin ConnectionPower Supply V3 Pin ConnectionCH340G/T/R2.93.33.6V
VCCVoltageVCC Pin CH340C/N/K/E/X/BVCC Pin CH340C/N/K/E/X/B3.13.33.6V
ICCOperatingOperatingCH340G/C/N/K/E/X/T/R412mA
ICCTotal Supply CurrentTotal Supply CurrentCH340B39mA
ISLPUSB SuspendUSB SuspendCH340G/K/T/R/B0.080.2mA
ISLPTotal Supply CurrentTotal Supply CurrentCH340C/N/E/X0.040.15mA
VILLow-Level Input VoltageLow-Level Input VoltageLow-Level Input Voltage00.8V
VIHHigh-Level Input VoltageHigh-Level Input VoltageHigh-Level Input Voltage1.9VCCV
VOLLow-Level Output Voltage (4mA sink current)Low-Level Output Voltage (4mA sink current)Low-Level Output Voltage (4mA sink current)0.5V
VOHHigh-Level Output Voltage (2mA source current) (Chip reset period only 40μA source current)High-Level Output Voltage (2mA source current) (Chip reset period only 40μA source current)High-Level Output Voltage (2mA source current) (Chip reset period only 40μA source current)VCC-0.6V
IUPInput Current of Input Pin with Built-in Pull-up ResistorInput Current of Input Pin with Built-in Pull-up ResistorInput Current of Input Pin with Built-in Pull-up Resistor370200μA
IDNInput Current of Input Pin with Built-in Pull-down ResistorInput Current of Input Pin with Built-in Pull-down ResistorInput Current of Input Pin with Built-in Pull-down Resistor-30-70-200μA
VRPower-on Reset Voltage ThresholdPower-on Reset Voltage ThresholdPower-on Reset Voltage Threshold2.42.62.8V

Related Variants

The following components are covered by the same datasheet.

Part NumberManufacturerPackage
C2977777
CH340BWCHSOP-16
CH340CWCHSOP-16
CH340GWCHSOP-16
CH340NWCHSOP-8
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