MAX13487EESA+

Drivers, Receivers, Transceivers Overview

The MAX13487EESA+T is a half-duplex, ±15kV ESD-protected RS-485-compatible transceiver featuring one driver and one receiver in an 8-pin SO package. It operates on a +5V supply (4.75V to 5.25V) with a maximum data rate of 500kbps. The device incorporates proprietary AutoDirection control, eliminating the need for external direction pins. Key features include hot-swap capability to prevent bus errors during power-up or live insertion, reduced slew-rate drivers to minimize EMI and reflections, and a 1/4-unit load receiver input impedance supporting up to 128 nodes. It provides ±15kV HBM protection and operates over an extended temperature range of -40°C to +85°C.

Drivers, Receivers, Transceivers Feature Summary

• AutoDirection Control Architecture: Internal state machine automatically manages driver and receiver states based on DI input and bus voltage, removing the requirement for discrete DE/RE control signals.
• Hot-Swap Capability: Integrated circuitry prevents false transitions and protects the bus during board insertion or power-up sequences by holding inputs in a safe state until VCC stabilizes.
• Reduced Slew-Rate Drivers: Controlled signal transition speeds minimize electromagnetic interference (EMI) and reduce signal reflections caused by improperly terminated cables.
• Robust Protection: Includes ±15kV Human Body Model ESD protection on A/B pins, short-circuit output current protection, and fail-safe receiver operation.

Drivers, Receivers, Transceivers Applications

• Isolated RS-485 Interfaces
• Utility Meters
• Industrial Controls
• Automated HVAC Systems

Drivers, Receivers, Transceivers Procurement Notes

Verify the component matches the exact part number MAX13487EESA+T, ensuring the 'E' suffix indicates the slew-rate limited version and 'ES' denotes the SOIC-8 package. Confirm RoHS compliance status as indicated by the '+' suffix. Check manufacturer documentation for lead-free packaging specifications and ensure the supplier provides valid traceability records for industrial-grade components.

Drivers, Receivers, Transceivers Selection Notes

Select this component when designing systems requiring simplified RS-485 interface control without external direction logic. It is suitable for applications needing robust ESD protection and hot-swap functionality. Ensure the application data rate does not exceed 500kbps; for higher speeds, consider the MAX13488E variant. Verify that the 1/4-unit load receiver impedance meets the network node count requirements.

Drivers, Receivers, Transceivers Part Context

The MAX13487E is part of the Maxim Integrated (now Analog Devices) MAX1348x family of high-speed RS-485 transceivers. This series is designed to simplify system design by integrating AutoDirection control, which replaces traditional discrete isolation components. The MAX13487E specifically targets applications where lower data rates and enhanced EMI performance are prioritized over maximum throughput.

Drivers, Receivers, Transceivers Replacement Considerations

MAX13488EESA+T offers identical pinout and features but supports data rates up to 16Mbps without slew-rate limiting. MAX13486EESA+T provides similar functionality with different fault protection characteristics. Standard RS-485 transceivers like MAX485 require external direction control and lack integrated hot-swap capabilities.

Drivers, Receivers, Transceivers FAQ

How does the AutoDirection feature eliminate the need for DE/RE pins?

The internal state machine monitors the DI input and the differential voltage between A and B. When DI goes low, it drives the bus. When DI goes high, it briefly drives then disables the driver, allowing pull-up/pull-down resistors to set the idle state, automatically switching between transmit and receive modes.

What is the purpose of the pull-up and pull-down resistors on the A and B lines?

These resistors are required for proper AutoDirection operation. They hold the bus in the high state (A-B > 200mV) following a low-to-high transition on the DI input, ensuring the receiver correctly identifies the idle state and preventing floating bus conditions.

How does the hot-swap capability protect the bus during power-up?

Upon power-up, internal switches pull the RE and DI pins high for a specific duration (15μs strong pullup, followed by a weak pullup). This ensures the driver remains disabled and the receiver is enabled in AutoDirection mode, preventing erroneous data transmission while the controlling processor initializes.