RS485/TTL Serial Converter Module

RS485/TTL Serial Converter Module is a TTL-to-RS485 interface designed to provide reliable serial communication between microcontrollers, embedded systems, and RS485-compatible devices. Built around the MAX487 RS485 transceiver, the module offers a compact and reliable solution for industrial automation, instrumentation, embedded systems, and other serial communication applications.

A dedicated TTL header provides direct access to RE, DE, RO, and DI signals, while onboard Power, TX, and RX LEDs provide communication status indication. Field connections are made through a four-position screw terminal and compatible header exposing 5 V, GND, RS485 A, and RS485 B signals.

 Features: 

MAX487 half-duplex RS485 transceiver:

• Compliant with TIA/EIA-485 standard.
• Maximum data rate: 250 kbps.
• Multi-drop bus network topology.
• Supports up to 128 nodes.

TTL UART interface:

• Direct access to RE, DE, RO, and DI.
• 5 V TTL logic.
• DI input with on-board 10 kΩ pull-up resistor for a defined logic state.
• UART baud rate up to 2 Mbps (limited to 250 Kbps by MAX487).

RS485 interface:

• On-board 120 Ω bus termination resistor.
• Differential A/B communication lines.

TVS array for ESD/transient protection.

Onboard status LEDs:

• Green: Power Indicator.
• Yellow: TX and RX Activity Indicators.

Interfaces:

• 6-pin TTL header: 5 V, GND, RE, DE, RO, D I.
• 4-pin header and screw terminal: 5 V, GND, A, B.
• Dimensions: 45.6 X 15.2mm.