MAX3490ESA+T

Overview

The MAX3490ESA+T is a full-duplex RS-485/RS-422 transceiver manufactured by Analog Devices Inc./Maxim Integrated. It operates from a single 3.3V supply (3.0V to 3.6V) and supports data rates up to 10Mbps. The device contains one driver and one receiver in an 8-pin SOIC package. It features fail-safe receiver inputs that guarantee a logic-high output when inputs are open, and drivers with short-circuit current limiting and thermal shutdown protection. The component operates within a temperature range of -40°C to +85°C.

Feature Summary

• Full-duplex communication capability without requiring separate enable pins for the driver or receiver
• Fail-safe receiver input design ensures a high logic state during open-circuit conditions
• Integrated thermal shutdown and current-limiting mechanisms protect against driver overload

Applications

• Telecommunications systems
• Industrial-control local area networks
• Transceivers for EMI-sensitive applications

Procurement Notes

Verify the specific suffix '+T' indicates tape-and-reel packaging configuration rather than a functional deviation. Confirm the 'E' designation corresponds to the industrial temperature range (-40°C to +85°C). Ensure the ordering information matches the exact manufacturer part number to avoid discrepancies in package type or electrical specifications.

Selection Notes

Select this component for applications requiring simultaneous bidirectional data transmission at speeds up to 10Mbps. It is suitable for 3.3V logic environments where charge pumps are undesirable. Consider alternatives like the MAX3485 if half-duplex operation with low-power shutdown is required instead of continuous full-duplex connectivity.

Part Context

This device belongs to the MAX34xx series of low-power transceivers designed for RS-485 and RS-422 communications. Unlike half-duplex variants such as the MAX3485, the MAX3490 provides dedicated transmit and receive paths, enabling true full-duplex operation without the need for external control signals to switch directions.

Replacement Considerations

MAX3490ESA: Identical electrical specifications and pinout; differs only in RoHS compliance status indicated by the '+' suffix.

FAQ

Does the MAX3490 support low-power shutdown mode?

No, the MAX3490 does not include Receiver Enable (RE) or Driver Enable (DE) pins and therefore cannot enter the low-power shutdown mode found in other members of the MAX34xx family.

What is the common-mode input voltage range?

The receiver inputs tolerate a common-mode voltage range from -7V to +12V.

How does the device handle open receiver inputs?

The receiver includes a fail-safe feature that guarantees a logic-high output if both the A and B inputs are left open circuit.