MAX485ESA+T

• Single Transmitter and Single Receiver RS-422/RS-485 Transceiver
• Half-Duplex Operation at Up to 2.5 Megabits per Second
• 4.75V to 5.25V supply, 500 uA Nominal Supply Current
• Differential Multi-Drop Bus Interface
• 8-Pin SOIC package, 5mm by 4mm, 1.75mm Height
• -40C to 85C Operating range, Lead-Free and RoHS Compliant

The Analog Devices MAX485ESA+T is a single transmitter and single receiver RS-422/RS-485 transceiver in an 8-pin SOIC measuring 5mm by 4mm with a 1.75mm height. It operates half duplex at up to 2.5 Mbps from a 4.75V to 5.25V supply drawing 500 uA. RS-485 is a differential multi-drop bus standard, and that differential signalling is what gives it the noise immunity and cable reach a single-ended interface such as RS-232 cannot approach. The device is specified from -40C to 85C, is lead-free and RoHS compliant and supplied in tape and reel; note the record's REACH SVHC status is Unknown, so a substance declaration should be requested if REACH documentation is required.

RS-485 transceivers are the physical layer of industrial fieldbus and building-automation networks: Modbus RTU and PROFIBUS links between PLCs, drives and sensors, DMX512 lighting control, BACnet and HVAC building networks, energy and utility meter buses, and the multi-drop links inside elevators, gates and access control systems. The differential pair is what allows a bus to run hundreds of metres through electrically noisy plant where a single-ended line would not survive. Half duplex with one driver and one receiver on two wires is the classic two-wire RS-485 topology, which is what the majority of installed field networks actually use. Design and maintenance teams keep this part in stock because its footprint and pinout have become the de facto standard for the function, making it a straightforward drop-in across many products.