CH340N SOP8 USB to serial port IC SOP-8

CH340N SOP8 USB to Serial Port IC SOP-8 is a highly cost-effective and compact solution that efficiently implements USB communication for standard UART serial ports. This integrated circuit provides the necessary interface logic, thus allowing microcontrollers and digital systems to establish communication with a PC over a USB connection seamlessly. Furthermore, its small SOP-8 package drastically reduces the required PCB space compared to larger alternatives. Consequently, designers frequently choose the CH340N for mass-produced embedded systems and IoT devices where both component cost and footprint are critical design factors. You can use this chip to upgrade legacy serial devices or embed USB connectivity directly onto new development boards, simplifying driver installation and ensuring broad operating system compatibility.

Key Features:

• Integrated Clock: The CH340N includes an internal clock generator, eliminating the need for an external crystal or resonator and minimizing component count.
• USB 2.0 Full-Speed: Supports USB 2.0 full-speed (12 Mbps), providing fast and reliable data transfer for serial communication.
• Wide Baud Rate Support: Handles common asynchronous serial port baud rates ranging from 50 bps up to 2 Mbps.
• Low External Component Count: Requires only minimal external components (typically two capacitors) to function, greatly simplifying the schematic and PCB layout.
• Driver Compatibility: Features built-in driver support for major operating systems, including Windows, macOS, and Linux, ensuring easy plug-and-play functionality.

Technical Specifications:

• Communication Standard: USB 2.0 Full Speed (12 Mbps)
• Serial Interface: Asynchronous Serial Port (UART)
• Baud Rate Range: 50 bps to 2,000,000 bps (≈ 2 Mbps)
• Operating Voltage (V_CC): 3.3 V or 5 V (Internally regulated logic levels)
• Operating Temperature Range: −40°C to +85°C (Industrial Grade)
• External Components: Typically requires two 10 nF capacitors on the USB data lines (V3 and GND).

Mechanical Specifications:

• Package Type: SOP-8 (Small Outline Package, 8-Pin)
• Mounting: Surface Mount Technology (SMT)
• Lead Style: Gull-wing leads
• Moisture Sensitivity Level (MSL): MSL 3 (Suitable for standard assembly processes)

Dimensions:

• Body Length: ≈ 4.9 mm
• Body Width: ≈ 3.9 mm
• Pin Pitch: 1.27 mm (Standard SOP pitch)
• Height: ≈ 1.75 mm
• Weight: ≈ 0.05 g (Extremely lightweight)

Pinout and Wiring:

• Pin 1 (V3): External capacitor connection (typically 10 nF to GND) for internal 3.3V power node.
• Pin 2 (GND): Connect to the circuit ground (0 V).
• Pin 3 (D+): Connect to the USB positive data line.
• Pin 4 (D−): Connect to the USB negative data line.
• Pin 5 (RXD): Serial data output pin (Receiving data from the PC). Connects to the host microcontroller’s TX pin.
• Pin 6 (TXD): Serial data input pin (Transmitting data to the PC). Connects to the host microcontroller’s RX pin.
• Pin 7 (VCC): Power supply input (3.3 V or 5 V).
• Pin 8 (RTS): Request-to-Send control signal (Optional).
• Wiring Note: Crucially, ensure decoupling capacitors are placed close to the VCC and V3 pins for stable operation.

Datasheet Reference:

• Download WCH CH340N Datasheet (Chinese/English)

Commonly Used in:

• Microcontroller Programming Boards: Providing the primary USB interface for uploading code to Arduino, ESP8266, and other MCU development platforms.
• USB-to-TTL Adapters: Forming the core logic for miniature serial debug and programming dongles.
• Embedded Systems: Integrated directly into custom hardware to offer a USB configuration and data logging port.

Applications:

• Serial Debugging and Diagnostics: Allowing developers to monitor and control embedded systems via a standard terminal application on a PC.
• Firmware Updates: Facilitating bootloader communication for in-field updates and programming.
• Data Logging: Hence, it enables the transfer of sensed data from an MCU to a computer for analysis and storage.
• USB Peripherals: Adding a virtual COM port to simple USB peripherals for configuration.

Equivalent Models:

• CP2102 (Silicon Labs): A popular alternative USB-to-UART bridge IC, though typically larger and more complex to implement.
• FT232RL (FTDI): The industry standard USB-to-serial converter, however, the CH340N offers a more economical BOM cost.
• PL2303 (Prolific): Another common bridge controller, often used in consumer-grade adapter cables.

Package Includes:

• 1 x CH340N SOP8 USB to serial port IC SOP-8