MAX33072EASA+T

Overview

The MAX33072EASA+T is a half-duplex RS-485/RS-422 transceiver in an 8-pin SOIC package. It operates on a supply voltage range of 3V to 5.5V with a typical supply current of 6mA. The device supports a maximum data rate of 500kbps and features ±65V fault protection, ±40V common-mode range, and ±40kV ESD protection on the A/B lines. It includes a polarity selection input (POL), true fail-safe receiver, hot-swap protection, and thermal shutdown at +160°C. Operating temperature ranges from -40°C to +125°C.

Feature Summary

• Integrated ±65V fault protection and ±40V common-mode range for robust communication in electrically noisy environments.
• Polarity selection input (POL) allows software correction of cross-wired field cables by swapping A and B data lines.
• True fail-safe feature guarantees a logic-high receiver output when inputs are open or shorted.
• Hot-swap protection safeguards against unwanted driver activation during board insertion into powered backplanes.

Applications

• Industrial automation equipment
• Home and building automation systems
• Agriculture and heavy machinery control
• Power supply and UPS monitoring
• Elevator control networks

Procurement Notes

Verify the specific ordering suffix to confirm packaging format. The 'T' suffix indicates tape and reel packaging, while absence of the suffix denotes tube packaging. Confirm RoHS compliance status via the '+' designation. Ensure the selected variant matches the required data rate specifications for the target application design.

Selection Notes

Select this component for applications requiring high overvoltage tolerance and polarity inversion flexibility. The MAX33072E variant is suitable for speeds up to 500kbps, whereas the MAX33073E supports up to 2Mbps. Consider the 1/8 unit load capability for bus configurations supporting up to 256 devices. Evaluate power dissipation requirements under high common-mode voltage conditions.

Part Context

This part belongs to the MAX33072E/MAX33073E family of fault-protected RS-485 transceivers designed for harsh industrial environments. It shares functional similarities with other Maxim Integrated interface ICs but distinguishes itself through integrated ±65V fault protection and polarity inversion capabilities without external components.

Replacement Considerations

The MAX33073EASA+T serves as a higher-speed alternative within the same family, supporting 2Mbps data rates. Verify pin compatibility and electrical characteristics before substitution. Other standard RS-485 transceivers may lack the integrated ±65V fault protection and polarity inversion features found in this device.

FAQ

How does the POL pin function?

The POL pin allows software control to swap the A and B data lines. Driving POL low enables normal operation, while driving it high swaps the lines to correct miswired field cables.

What is the fail-safe behavior of the receiver?

The device guarantees a logic-high receiver output when the inputs are open, shorted, or connected to a terminated line with all drivers disabled.

What happens during a thermal shutdown event?

When the junction temperature exceeds +160°C, the driver outputs are disabled and RO goes high impedance. Outputs re-enable when the temperature falls below +148°C.