MAX3085EESA+T

Overview

The MAX3085EESA+T is a half-duplex RS-485/RS-422 transceiver manufactured by Analog Devices Inc./Maxim Integrated. It operates from a single +5V supply (4.75V to 5.25V) and supports data rates up to 500kbps with slew-rate-limited drivers. The device features ±15kV ESD protection on all I/O pins, fail-safe receiver circuitry guaranteeing a logic-high output when inputs are open or shorted, and low quiescent current of 375µA typical. It includes thermal shutdown and short-circuit current limiting for driver protection. Packaged in an 8-pin SOIC, it operates within a temperature range of -40°C to +85°C.

Feature Summary

• Enhanced ESD protection rated at ±15kV Human Body Model for all transmitter outputs and receiver inputs.
• Fail-safe receiver design ensures a logic-high output state during bus idle conditions or input faults.
• Slew-rate-limited driver architecture minimizes electromagnetic interference and signal reflections.
• Integrated thermal shutdown and short-circuit current limiting protect the driver under fault conditions.

Applications

• RS-422 and RS-485 communication networks
• Industrial control local area networks
• Transceivers for EMI-sensitive applications

Procurement Notes

Verify the component authenticity through official manufacturer channels or authorized distributors. Confirm that the ordering suffix matches the required package type and temperature grade. Ensure compliance with RoHS directives if applicable to the specific production batch. Cross-reference the datasheet revision to confirm pinout and electrical characteristics align with system requirements before procurement.

Selection Notes

Select this component for applications requiring reliable half-duplex communication over twisted-pair lines. The MAX3085E is suitable where moderate data speeds up to 500kbps are sufficient. Consider the enhanced ESD protection for environments prone to electrostatic discharge. Verify that the 8-pin SOIC package fits the available PCB footprint and that the operating temperature range meets environmental constraints.

Part Context

This part belongs to the MAX3080E–MAX3089E family of high-speed transceivers. It shares pin compatibility with industry-standard devices like the 75180 but offers improved ESD protection and fail-safe features. The 'E' suffix indicates an extended industrial temperature range, while '+T' denotes tape-and-reel packaging. It is designed as a drop-in replacement for legacy RS-485 interfaces with enhanced robustness.

Replacement Considerations

Pin-compatible alternatives include the MAX3485E and MAX485E series. Verify that substitute parts support the required 500kbps data rate and ±15kV ESD protection levels. Check if the alternative maintains the same fail-safe threshold and half-duplex configuration to ensure functional equivalence in existing designs.