MAX3157EAI+T

Overview

The MAX3157EAI+T is a high CMRR RS-485/RS-422 data-communications interface providing ±50V isolation in a hybrid microcircuit. It operates at data rates up to 250kbps with a single +5V supply (4.75V to 5.25V). The device contains one transmitter and one receiver, drawing 25mA typical supply current, which drops to 25µA in shutdown mode. It features thermal shutdown for driver overload protection and fail-safe receiver circuitry. Operating temperature range is -40°C to +85°C.

Feature Summary

• Provides ±50V isolation using external capacitors for power transfer from the logic side.
• Features pin-selectable full-duplex or half-duplex operation modes.
• Includes independently programmable receiver and transmitter output phase controls.
• Offers true fail-safe receiver functionality while maintaining EIA/TIA-485 compliance.

Applications

• Industrial Controls
• Telecommunications
• Local Area Networks

Procurement Notes

Verify the specific suffix requirements against official documentation before procurement. Confirm that the ordering code matches the exact package type and temperature grade required for the design. Ensure compatibility with existing inventory specifications and check for any recent product lifecycle changes or obsolescence notices from the manufacturer.

Selection Notes

Select this component when isolated RS-485 or RS-422 communication is required without optical isolation. Consider the ±50V isolation limit and the need for external charge-pump capacitors. Evaluate the 250kbps maximum data rate against system requirements. Verify that the 28-pin SSOP package fits the PCB layout constraints and thermal management needs.

Part Context

The MAX3157 series serves as a low-cost replacement for opto-isolated transceivers in industrial applications. The 'E' designation indicates an extended temperature range of -40°C to +85°C. The 'AI' suffix specifies the 28-pin SSOP package. This part belongs to the broader family of isolated interface solutions designed for robust data transmission in electrically noisy environments.

Replacement Considerations

Refer to the MAX1480 family data sheet for fully isolated RS-485/RS-422 transceiver alternatives. Check for direct pin-compatible replacements if upgrading isolation levels or data rates are necessary. Verify that any substitute maintains the required ±50V isolation capability and operating temperature range.