MAX3080EESD+T

Overview

The MAX3080EESD+T is a high-speed RS-485/RS-422 transceiver manufactured by Analog Devices Inc./Maxim Integrated. It contains one driver and one receiver, operating from a single +5V supply (4.75V to 5.25V). The device supports full-duplex communication with a maximum data rate of 115kbps due to slew-rate limiting. It features ±15kV ESD protection on all I/O pins and fail-safe circuitry that guarantees a logic-high receiver output when inputs are open or shorted. The quiescent current is typically 375µA, with a low-current shutdown mode available. It is housed in a 14-pin SOIC package and operates within a temperature range of -40°C to +85°C.

Feature Summary

• Enhanced ESD protection for RS-485 I/O pins rated at ±15kV using the Human Body Model.
• True fail-safe receiver design that maintains EIA/TIA-485 compatibility while ensuring a logic-high output during bus idle or fault conditions.
• Slew-rate-limited drivers minimize electromagnetic interference (EMI) and reduce signal reflections on improperly terminated cables.
• Low-current shutdown mode reduces power consumption significantly when the device is not actively transmitting or receiving.

Applications

• RS-422 and RS-485 communications networks
• Level translators for differential signaling systems
• Transceivers designed for EMI-sensitive industrial applications
• Industrial-control local area networks

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type, temperature range, and tape-and-reel specifications. Ensure the component matches the required RoHS compliance status and lead-free finish requirements for your assembly process. Cross-reference the part number with authorized distributors to confirm availability and authenticity before placing orders.

Selection Notes

Select this component for applications requiring robust ESD protection and fail-safe operation on RS-485/RS-422 buses. The slew-rate limitation makes it suitable for longer cable runs where signal integrity is critical. Verify that the system voltage aligns with the +5V requirement and that the 115kbps data rate meets the application's throughput needs. Consider the 14-pin SOIC package dimensions for PCB layout constraints.

Part Context

The MAX3080E is part of the MAX3080E–MAX3089E family of high-speed transceivers. This family offers various configurations including half-duplex options, higher speed variants up to 10Mbps, and programmable models like the MAX3089E. The MAX3080E specifically provides a fixed full-duplex configuration with reduced slew rates for noise reduction, distinguishing it from the faster, unrestricted slew-rate models in the same series.

Replacement Considerations

The datasheet notes pin compatibility with the industry-standard 75180 transceiver. When substituting, verify that the replacement part supports the same +5V supply, full-duplex operation, and fail-safe thresholds. Ensure the substitute also offers comparable ESD protection levels and thermal characteristics for the intended operating environment.

FAQ

What is the fail-safe behavior of the MAX3080E receiver?

The fail-safe circuitry guarantees a logic-high receiver output when the receiver inputs are open, shorted, or connected to a terminated transmission line with all drivers disabled. This occurs because the receiver threshold is set between -50mV and -200mV, resulting in a logic high when the differential input voltage is pulled to 0V by termination resistors.

How does the slew-rate limiting affect data transmission?

The MAX3080E features reduced slew-rate drivers that minimize electromagnetic interference (EMI) and reduce reflections caused by improperly terminated cables. This allows for error-free data transmission up to 115kbps, making it suitable for noisy environments or longer cable runs compared to unrestricted slew-rate devices.

What is the purpose of the shutdown mode in this transceiver?

The shutdown mode allows the device to enter a low-power state by driving the RE pin high and the DE pin low. In this mode, both the driver and receiver outputs are placed in a high-impedance state, and the supply current drops significantly to approximately 1nA, reducing overall power consumption when the bus is inactive.