## Product Overview The UIC321H is a highly reliable USB-to-RS232 adapter featuring full isolation between the RS232 port and the USB interface. Built around the Silicon Labs CP2102N chipset — one of the most robust and compatible serial conversion chips available — it ensures broad operating system compatibility, including with Windows, Linux (kernel 3.0.0-19 and above), macOS 8 and above, and Android. This adapter provides **3000 VDC isolation** for both power and data lines, supporting data rates up to 120 kbps. It also includes strong ESD protection on the TX and RX pins: **±8 kV** for contact discharge and **±15 kV** for air gap discharge. This makes it an excellent safeguard for both your USB port and connected serial devices against voltage spikes, static discharge, and transient surges. Designed for industrial environments, this adapter performs reliably in electrically noisy conditions and where RS232 cables are frequently connected and disconnected. The durable cast metal enclosure offers added mechanical protection, and the unit draws power directly from the USB port — no external power supply required. --- ## Features :::grid{cols=2 style=card} **Isolated RS232 Interface** - 3000 VDC full isolation (power + signal) - DB9 Male connector - Isolated TX, RX and GND signals - Baud rates up to 115200 bps **ESD Protection** - TX/RX: ±8 kV (contact) - IEC 61000-4-2: 15 kV (Level 4) - MIL-STD-883 3015.7: 15 kV ::: :::grid{cols=2 style=card} **USB Interface** - USB 2.0 full-speed (12 Mbps) - USB-powered, no external power needed - Emulates standard COM port - Broad OS support (Win/Linux/macOS/Android) **Industrial Design** - Cast aluminum alloy enclosure - Cable length: 3 ft (100 cm) - Operating temp: -40°C to +85°C - Weight: 75 g ::: --- ## Specifications ### General Information | Parameter | Specification | |-----------|---------------| | Part Number | UIC321H | | Operating System | Windows (32/64-bit), Linux (kernel 3.0.0-19+), macOS 8+, Android | | USB Connector | Type A, Cast Aluminum Alloy | | USB Compliance | USB 1.1 / 2.0 | | Power | From USB port (no external power required) | ### RS232 Interface | Parameter | Specification | |-----------|---------------| | Connector | DB9 Male, Metal Case | | Isolation | 3000 VDC (power + signal) | | Signals | Isolated TX, RX and GND | | Baud Rates | 300, 600, 1200, 1800, 2400, 4000, 4800, 7200, 9600, 14400, 16000, 19200, 28800, 38400, 51200, 56000, 57600, 64000, 76800, 115200 bps | | Data Bits | 5, 6, 7, 8 | | Stop Bits | 1, 1.5, 2 | | Parity | None, Odd, Even, Mark, Space | ### ESD Protection | Parameter | Specification | |-----------|---------------| | TX / RX Pins | ±8 kV (contact) | | IEC 61000-4-2 (Direct discharge) | 15 kV (Level 4) | | IEC 61000-4-2 (Air discharge) | 15 kV (Level 4) | | MIL-STD-883, Method 3015.7 | 15 kV | ### Mechanical & Environmental | Parameter | Specification | |-----------|---------------| | Enclosure | Aluminum | | Cable Length | 3 ft (100 cm) | | Weight | 75 g | | Operating Temperature | -40°C to +85°C | | Operating Humidity | 5% to 85% RH | | Warranty | 1-year limited warranty | --- ## Pinout ### DB9 Male Connector | Pin | Signal | Direction | Description | |-----|--------|-----------|-------------| | 2 | TX | Output | Transmit data to RS232 device | | 3 | RX | Input | Receive data from RS232 device | | 5 | GND | — | Signal ground | > **Note**: The UIC321H uses a 3-wire RS232 interface (TX, RX, GND). Hardware flow control signals (RTS/CTS) are not supported. --- ## Quick Start 1. Connect the UIC321H to your computer via USB 2. Install the CP2102N driver (if not automatically recognized) 3. Connect the DB9 connector to your RS232 device 4. Open a serial terminal (e.g., PuTTY, Serial Monitor) 5. Select the correct COM port and baud rate 6. Communication is ready --- ## Safety Precautions ### Electrical Safety | Hazard | Precaution | |--------|------------| | Isolation Voltage | Do not exceed 3000 VDC isolation rating. Ensure proper grounding. | | ESD | Use anti-static precautions when handling. Discharge static before touching connectors. | | Power Supply | The device is USB-powered. Ensure the USB port can supply sufficient current. | ### Operational Safety | Hazard | Precaution | |--------|------------| | Operating Temperature | Use within -40°C to +85°C range. | | Humidity | Keep within 5% to 85% RH. Do not use in condensing environments. | | Cable Strain | Avoid sharp bends or pulling on the USB cable. | --- ## Video Tutorial :::video[Universal USB to RS232 Serial Converter Adapter, Industrial Grade 3000V Fully Isolated, Silicon Labs](https://www.youtube.com/watch?v=w3OdJKVyuWU) ::: --- ## Downloads - 📖 [UIC321H Datasheet V5.10 (PDF)](https://www.uirobot.com/uploads/files/Manual_UIC321H%20V5.10.pdf) - 💻 [CP2102N USB Driver](https://www.silabs.com/developers/usb-to-uart-bridge-vcp-drivers) --- ## Related Documents - [UIC320A USB to UART (TTL) Adapter](/docs/uic320a) - [Quick Start Guide](/docs/quick-start) - [Python CAN Bus Examples](/docs/python-examples) --- *Last updated: 2026-06-25 | Based on Datasheet V5.10*