Waveshare TTL to RS485 (C) Galvanic Isolated Converter Half-Duplex Communication Module

The Waveshare TTL to RS485 (C) is a compact, high-reliability module that converts TTL-level signals (3.3V or 5V) to RS485 differential signals with full galvanic isolation. Designed for industrial and embedded applications, it ensures robust communication over long distances while protecting connected devices from electrical surges and interference.

Pinout Overview

Right Side (TTL Interface):

• VCC: Power Input (3.3V ~ 5V DC)
• TXD: TTL Transmit Data
• RXD: TTL Receive Data
• GND: Ground / TTL Signal Ground

Left Side (RS485 Interface):

• A+: RS485 Differential Signal Positive
• B-: RS485 Differential Signal Negative
• PE: RS485 Signal Ground

Features

• TTL to RS485 Conversion: Converts TTL signals to differential RS485, supporting half-duplex communication
• Wide Voltage Compatibility: Accepts 3.3V to 5V TTL input levels
• Galvanic Isolation: Built-in power and digital isolation enhances safety and signal integrity without requiring an external isolated power supply
• Multi-Layer Protection:
• Onboard TVS (Transient Voltage Suppressor) for surge and spike suppression
• Self-recovery fuse and protection diodes for over-current and over-voltage protection
• 200W lightning-proof and 6KV ESD protection for RS485 interface
• 120 Terminal Resistor: Optional onboard resistor can be enabled via soldering for impedance matching
• Compact Design: Castellated holes with black immersion gold finish for easy PCB integration

Applications

• Industrial automation and control systems
• RS485 sensor networks and data acquisition systems
• Long-distance UART communication
• Embedded systems requiring robust serial communication

Specification