MAX481ECSA+

Overview

The MAX481ECSA+ is a low-power, half-duplex RS-485 and RS-422 transceiver manufactured by Analog Devices Inc./Maxim Integrated. It integrates one driver and one receiver within an 8-pin SOIC package. The device operates from a single +5V supply (4.75V to 5.25V) and supports data rates up to 2.5Mbps with unrestricted slew rates. Key electrical specifications include ±15kV ESD protection on all pins, a typical no-load supply current of 300µA, and a shutdown mode consuming only 0.5µA. It features thermal shutdown and short-circuit current limiting for the driver, along with fail-safe receiver inputs that guarantee a logic-high output when open.

Feature Summary

• Provides ±15kV electrostatic discharge (ESD) protection on driver outputs and receiver inputs without latchup.
• Features a low-current shutdown mode that reduces supply consumption to 0.5µA when both driver and receiver are disabled.
• Includes driver protection against excessive power dissipation via thermal shutdown circuitry and short-circuit current limiting.
• Receiver input incorporates a fail-safe feature that ensures a logic-high output state if the differential input terminals are left open.

Applications

• Low-Power RS-485 Transceivers
• Low-Power RS-422 Transceivers
• Level Translators
• Transceivers for EMI-Sensitive Applications
• Industrial-Control Local Area Networks

Procurement Notes

Verify the specific ordering suffix to confirm the package type and temperature range. The 'C' suffix indicates commercial operating temperature, while 'S' denotes the SOIC package. Confirm RoHS compliance status through official manufacturer documentation or authorized distributors before finalizing procurement decisions.

Selection Notes

Select this component for applications requiring high-speed transmission up to 2.5Mbps where unrestricted slew rates are necessary. It is suitable for harsh environments due to robust ESD protection. Ensure the system design accommodates the 5V supply requirement and utilizes the shutdown capability if ultra-low standby power is critical for the application.

Part Context

This device belongs to the MAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E family of low-power transceivers designed for RS-485 and RS-422 communications. The 'E' designation signifies enhanced ESD protection compared to standard versions. The MAX481E specifically offers unrestricted slew rates for higher data throughput compared to slew-rate-limited variants in the same series.

Replacement Considerations

Pin-compatible alternatives within the same series include the MAX481EEPA (Plastic DIP) and MAX481EESA (SOIC, Extended Temperature). Verify that replacement parts match the required operating temperature range and package dimensions for the specific board layout.

FAQ

How is the low-power shutdown mode activated?

Shutdown is initiated by bringing the Receiver Enable (-RE-) pin high and the Driver Enable (DE) pin low simultaneously. The device will not enter shutdown unless both conditions are met for at least 600ns.

What is the maximum data rate supported by the MAX481E?

The MAX481E supports data rates up to 2.5Mbps because its driver slew rate is not limited, unlike other members of the family such as the MAX483E which are limited to 250kbps.

Does the receiver have a fail-safe feature?

Yes, the receiver input has a fail-safe feature that guarantees a logic-high output if the input is open circuit.