MAX3078EESA+

Overview

The MAX3078EESA+ is a half-duplex RS-485 transceiver manufactured by Analog Devices Inc./Maxim Integrated. It operates on a single +3.3V supply and features one driver and one receiver. The device supports data transmission rates up to 16Mbps with unrestricted slew rates. It includes ±15kV ESD protection, fail-safe circuitry ensuring a logic-high output when inputs are open or shorted, and hot-swap capability to prevent false transitions during power-up. The component is housed in an 8-pin SOIC package and functions within an operating temperature range of -40°C to +85°C.

Feature Summary

• Hot-swap input structure on DE and RE pins eliminates false bus transitions during board insertion or power-up sequences.
• Fail-safe receiver guarantees a logic-high output state when differential inputs are open, shorted, or connected to a terminated bus with all drivers disabled.
• Unrestricted driver slew rates enable high-speed data transmission up to 16Mbps without the signal limitations found in lower-speed variants.

Applications

• Industrial Control Systems
• Telecommunications Equipment
• Security Systems
• Instrumentation

Procurement Notes

Verify the specific ordering suffix against official documentation to confirm package type and temperature grade. Confirm RoHS compliance status through manufacturer datasheets. Ensure the source provides valid traceability for the Analog Devices/Maxim Integrated brand. Check for any regional distribution restrictions that may affect availability.

Selection Notes

Select this model specifically for half-duplex RS-485 applications requiring high-speed communication up to 16Mbps. Unlike the MAX3070E series which limits slew rates for EMI reduction at lower speeds, this variant prioritizes maximum throughput. Ensure the design accommodates the lack of internal slew-rate limiting for proper cable termination strategies.

Part Context

This component belongs to the MAX3070E–MAX3079E family of +3.3V, ±15kV ESD-protected RS-485 transceivers. Within this series, the MAX3078E is distinguished by its half-duplex configuration and unrestricted driver slew rates, contrasting with full-duplex models like the MAX3070E or slew-limited variants such as the MAX3072E.

Replacement Considerations

Publicly confirmed substitute part numbers include MAX3078EESA+T (tape and reel packaging) and MAX3078EESA+R (reel packaging). These variants share identical electrical characteristics and pinouts with the MAX3078EESA+.

FAQ

How does the MAX3078E handle bus contention during hot insertion?

The device features hot-swap capability on the Driver Enable (DE) and Receiver Enable (RE) pins. Internal circuitry holds DE low and RE high during power-up, preventing erroneous data transfer while the system processor initializes.

What is the receiver behavior when the bus lines are disconnected?

The MAX3078E incorporates fail-safe circuitry that guarantees a logic-high receiver output if the A and B inputs are open, shorted, or if all transmitters on a terminated bus are disabled.

Is the driver slew rate adjustable on the MAX3078E?

No, the MAX3078E driver slew rates are not limited. This allows for transmit speeds up to 16Mbps, unlike the MAX3070E/MAX3071E/MAX3072E which feature reduced slew rates for lower data rates.