MAX14770EESA+T

Drivers, Receivers, Transceivers Overview

The MAX14770EESA+T is a half-duplex RS-485 transceiver designed for PROFIBUS-DP and industrial fieldbus applications. It operates on a single +4.5V to +5.5V supply with a typical no-load supply current of 2.5mA and a shutdown current of 15µA. The device supports data rates up to 20Mbps and features ±35kV HBM ESD protection on the A and B pins, along with ±12kV contact and ±15kV air gap IEC 61000-4-2 protection. It includes true fail-safe receiver circuitry, short-circuit protected outputs, and thermal shutdown. The component is housed in an 8-pin SO package and functions within an operating temperature range of -40°C to +85°C.

Drivers, Receivers, Transceivers Feature Summary

• Integrated high-voltage electrostatic discharge protection on differential signal lines ensures robustness against harsh electrical environments.
• True fail-safe receiver guarantees a logic-high output state when inputs are open or shorted, preventing false transitions.
• Hot-swap input structure prevents bus disturbances during power-up or board insertion by holding enable pins in safe states.
• Low-power shutdown mode significantly reduces supply current consumption when the device is not actively transmitting or receiving.

Drivers, Receivers, Transceivers Applications

• PROFIBUS-DP Networks
• Industrial Fieldbuses
• Motion Controllers
• RS-485 Networks
• Machine Encoders

Drivers, Receivers, Transceivers Procurement Notes

Verify the specific ordering suffix to confirm the package type and temperature rating. The 'ES' suffix indicates an 8-pin Small Outline package with an extended temperature range of -40°C to +85°C. Confirm that the '+T' designation matches the required tape and reel packaging format for automated assembly processes. Ensure compliance with RoHS standards as indicated by the '+' symbol in the part number.

Drivers, Receivers, Transceivers Selection Notes

Select this component for applications requiring high ESD immunity on the communication bus without external protection components. The 1/4 unit load receiver impedance allows for connecting up to 128 devices on a single bus segment. Consider the thermal characteristics if operating near the upper limits of the specified junction temperature range. Verify that the 20Mbps maximum data rate meets the system's throughput requirements.

Drivers, Receivers, Transceivers Part Context

This device belongs to the MAX14770E series of high-ESD protected transceivers manufactured by Analog Devices Inc./Maxim Integrated. It utilizes BiCMOS technology to combine high-speed performance with low power consumption. The series is specifically engineered to meet the stringent requirements of PROFIBUS-DP Class 3 networks while maintaining compatibility with standard RS-485 and RS-422 protocols.

Drivers, Receivers, Transceivers Replacement Considerations

MAX14770EGSA+T offers the same functionality in an 8-pin SO package but with an extended temperature range of -40°C to +105°C.

Drivers, Receivers, Transceivers FAQ

How does the MAX14770E handle hot-swap conditions?

The device features internal pulldown circuits on the DE pin and pullup circuits on the RE pin. These circuits activate during power-up to hold the driver disabled and receiver enabled, preventing data errors caused by floating inputs during board insertion or power sequencing.

What is the receiver threshold behavior in a fail-safe condition?

The receiver is designed with a threshold between -50mV and -200mV. If the differential input voltage (A-B) is greater than or equal to -50mV, the output is logic-high. This ensures a high output when inputs are open, shorted, or terminated with all drivers disabled.

What protections are provided against excessive power dissipation?

The transceiver includes short-circuit foldback current limiting on the driver outputs and a thermal-shutdown circuit. If the junction temperature exceeds approximately +160°C, the driver outputs enter a high-impedance state until the temperature cools by about 15°C.