CH340C
USB to serial chipThe CH340C is a usb to serial chip from WCH. View the full CH340C datasheet below including key specifications, absolute maximum ratings.
CH340C shares its datasheet with CH340B, whose page lists every part number it covers.
Official CH340C datasheet (PDF) — the source this page was extracted from.
CH340C Key Specifications
| Parameter | Value |
|---|---|
| Clock | Built-in, no external crystal required |
| USB Interface | Full-speed, USB 2.0 compatible |
| Baud Rate Range | 50bps to 2Mbps |
| Serial Interface | Hardware full-duplex UART with transceiver buffer |
| Handshake Signals | RTS, DTR, DCD, RI, DSR, CTS |
| Storage Temperature | -55°C to 125°C |
| Operating Temperature | -20°C to 70°C |
| Operating Supply Current | 7mA typ, 20mA max |
| Supply Voltage (5V Mode) | 4.0V to 5.3V |
| Transmit Baud Rate Error | <1.8% |
| Supply Voltage (3.3V Mode) | 3.3V (VCC connected to V3) |
| Absolute Max Supply Voltage | -0.5V to 6.0V |
| Receive Baud Rate Tolerance | approx. 2% |
CH340C 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
CH340C 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.
CH340C Absolute Maximum Ratings
| Name | Parameter Description | Parameter Description | Min | Max | Unit |
|---|---|---|---|---|---|
| TA | Operating | CH340G/T/R | -40 | 85 | °C |
| TA | Ambient Temperature | CH340C/N/K/E/X/B | -20 | 70 | °C |
| TS | Storage Ambient Temperature | Storage Ambient Temperature | -55 | 125 | °C |
| VCC | Power Supply Voltage | (VCC connected to power, GND connected to ground) | -0.5 | 6.0 | V |
| VIO | Voltage on Input or Output Pin | Voltage on Input or Output Pin | -0.5 | VCC+0.5 | V |
- 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)
| Name | Parameter Description | Parameter Description | Min | Typ | Max | Unit |
|---|---|---|---|---|---|---|
| VCC | Power Supply Voltage | V3 pin only external capacitor, not connected to VCC | 4.0 | 5 | 5.3 | V |
| ICC | Operating CH340G/C/N/K/E/X/T/R | Operating CH340G/C/N/K/E/X/T/R | 7 | 20 | mA | |
| ICC | Total Supply Current CH340B | Total Supply Current CH340B | 6 | 15 | mA | |
| ISLP | USB Suspend CH340G/K/T/R/B | USB Suspend CH340G/K/T/R/B | 0.09 | 0.2 | mA | |
| ISLP | Total Supply Current CH340C/N/E/X | Total Supply Current CH340C/N/E/X | 0.05 | 0.15 | mA | |
| VIL | Low-Level Input Voltage | Low-Level Input Voltage | 0 | 0.9 | V | |
| VIH | High-Level Input Voltage | High-Level Input Voltage | 2.3 | VCC | V | |
| VOL | Low-Level Output Voltage (6mA sink current) | Low-Level Output Voltage (6mA sink current) | 0.5 | V | ||
| VOH | High-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-0.6 | V | ||
| IUP | Input Current of Input Pin with Built-in Pull-up Resistor | Input Current of Input Pin with Built-in Pull-up Resistor | 3 | 150 | 300 | μA |
| IDN | Input Current of Input Pin with Built-in Pull-down Resistor | Input Current of Input Pin with Built-in Pull-down Resistor | -40 | -100 | -300 | μA |
| VR | Power-on Reset Voltage Threshold | Power-on Reset Voltage Threshold | 2.4 | 2.6 | 2.8 | V |
| Name | Parameter Description | Parameter Description | Parameter Description | Min | Typ | Max | Unit |
|---|---|---|---|---|---|---|---|
| VCC | Power Supply V3 Pin Connection | Power Supply V3 Pin Connection | CH340G/T/R | 2.9 | 3.3 | 3.6 | V |
| VCC | Voltage | VCC Pin CH340C/N/K/E/X/B | VCC Pin CH340C/N/K/E/X/B | 3.1 | 3.3 | 3.6 | V |
| ICC | Operating | Operating | CH340G/C/N/K/E/X/T/R | 4 | 12 | mA | |
| ICC | Total Supply Current | Total Supply Current | CH340B | 3 | 9 | mA | |
| ISLP | USB Suspend | USB Suspend | CH340G/K/T/R/B | 0.08 | 0.2 | mA | |
| ISLP | Total Supply Current | Total Supply Current | CH340C/N/E/X | 0.04 | 0.15 | mA | |
| VIL | Low-Level Input Voltage | Low-Level Input Voltage | Low-Level Input Voltage | 0 | 0.8 | V | |
| VIH | High-Level Input Voltage | High-Level Input Voltage | High-Level Input Voltage | 1.9 | VCC | V | |
| VOL | Low-Level Output Voltage (4mA sink current) | Low-Level Output Voltage (4mA sink current) | Low-Level Output Voltage (4mA sink current) | 0.5 | V | ||
| VOH | 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) | High-Level Output Voltage (2mA source current) (Chip reset period only 40μA source current) | VCC-0.6 | V | ||
| IUP | Input Current of Input Pin with Built-in Pull-up Resistor | Input Current of Input Pin with Built-in Pull-up Resistor | Input Current of Input Pin with Built-in Pull-up Resistor | 3 | 70 | 200 | μA |
| IDN | Input Current of Input Pin with Built-in Pull-down Resistor | Input Current of Input Pin with Built-in Pull-down Resistor | Input Current of Input Pin with Built-in Pull-down Resistor | -30 | -70 | -200 | μA |
| VR | Power-on Reset Voltage Threshold | Power-on Reset Voltage Threshold | Power-on Reset Voltage Threshold | 2.4 | 2.6 | 2.8 | V |
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.
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