MAX485 RS485 to TTL UART Converter Module with Automatic Flow Control

RS485 to TTL UART Conversion for Serial Communication

The MAX485 RS485 to TTL UART Converter Module connects a TTL-level serial interface to an RS485 bus. With automatic transmit/receive direction control and support for 3.3V and 5V power supplies and logic signals, it simplifies adding RS485 communication to your electronics projects.

When you are building a serial communication link, onboard TXD and RXD indicators make it easier to monitor transmit and receive activity. Automatic direction control removes the need for a separate transmit/receive control signal, helping keep your interface wiring straightforward.

Key Features

• TTL UART to RS485 interface: Connect a UART-based circuit to an RS485 communication bus.
• Automatic flow control: Hardware-controlled transmit/receive switching without a separate direction-control connection.
• 3.3V and 5V support: Compatible with both supply voltages and logic levels, as specified in the existing product documentation.
• TXD and RXD indicators: Check serial transmission and reception activity during setup and testing.
• Selectable 120-ohm termination: Enable the onboard termination resistor by shorting the R0 pads when required by your bus layout.
• Prototype-friendly design: Standard 2.54 mm pitch, semi-hole pads and a thin 0.8 mm PCB for integration into projects.

Specifications

• Listed transceiver: MAX485
• Serial interfaces: TTL UART and RS485
• Supply voltage: 3.3V or 5V
• Supported logic levels: 3.3V and 5V
• TTL-side connections: RX, TX, power and GND
• Termination: 120 ohms, selectable through R0 pads
• Signal indicators: TXD and RXD
• PCB thickness: 0.8 mm
• Listed operating temperature: -40°C to +85°C

Project Applications

Use this converter for UART-to-RS485 interfacing, microcontroller communication experiments and wired serial networking projects. It can provide the physical interface for a Modbus RTU project when your controller and software implement the required protocol; the module itself does not add Modbus functionality.

Connection and Installation Notes

Check the board markings, supply voltage and signal connections before applying power. Configure termination to suit the complete RS485 network rather than enabling it on every module. The original listing describes cable runs of up to 800 metres; actual usable distance depends on cable, baud rate, termination and installation conditions, so test your intended setup before deployment.

Choose this module when you need an RS485 serial interface with automatic direction control and convenient transmit/receive activity indicators.