RS485/USB-B Serial Converter Module

The RS485/USB-V Serial Converter Module is an industrial-grade USB-to-RS485 interface designed to provide reliable serial communication between a host computer and RS485-compatible devices. Built around the CH340B USB-to-UART bridge and MAX487 RS485 transceiver, the module offers a compact and reliable solution for industrial automation, embedded systems, instrumentation, and other industrial communication applications.

Designed for dependable operation in demanding environments, the module incorporates industrial-grade protection circuitry and an optimized PCB layout to improve reliability and noise immunity. A USB Type-B connector enables convenient plug-and-play operation, while onboard Power, TX, and RX LEDs provide communication status indication. Field connections are made through a four-position screw terminal exposing 5 V, GND, RS485 A, and RS485 B signals.

  Features: 

• CH340B USB-to-UART Bridge.
• 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.

• USB Type-B Female Connector:

 USB Powered (5V).

UART Baud Rate up to 2 Mbps (Limited to 250 Kbps by MAX487).

• On-board 120 Ω bus termination resistor.
• Supports Windows 7, 8, 10, and 11 (32-bit & 64-bit).
• Industrial Protection Circuitry.

Resettable PTC Fuse.

Ferrite Bead for EMI/ESD Suppression.

Reverse-Polarity Protection.

• Optimized PCB Grounding for Improved Noise Immunity.
• Isolated USB Shield Ground Connection.
• Onboard Status LEDs:

GREEN:  Power Indicator.

YELLOW: TX and RX Activity Indicator.

• Four-Pin Screw Terminal (5V, 0V, A, B).
• Compact, Plug-and-Play Design.
• Dimensions: 45.7 X 2.8mm.