MAX3491ECPD

Overview

The MAX3491ECPD is a full-duplex RS-485/RS-422 transceiver operating from a single +3.0V to +3.6V supply without a charge pump. It supports data rates up to 12Mbps with a typical propagation delay of 22ns and driver skew of ±8ns. The device features ±15kV ESD protection (HBM, IEC Air-Gap) and ±8kV contact discharge. It includes a low-power shutdown mode drawing 2nA typical current. Operating temperature range is 0°C to +70°C in a 14-pin Plastic DIP package.

Feature Summary

• Full-duplex communication capability with independent driver and receiver control
• Robust ±15kV electrostatic discharge protection on all I/O pins
• Low-power shutdown mode for significant energy savings
• Fail-safe receiver guarantees high output when inputs are open

Applications

• Telecommunications systems
• Industrial-control local area networks
• EMI-sensitive applications requiring reduced reflections
• Integrated Services Digital Networks (ISDN)
• Packet switching environments

Procurement Notes

Verify the specific suffix 'CPD' corresponds to the Plastic DIP package and commercial temperature grade (0°C to +70°C). Confirm RoHS compliance status via the manufacturer's official documentation or ordering information section, as suffixes may indicate lead-free variants. Cross-reference the part number against the latest Analog Devices/Maxim Integrated selector guide to ensure availability and correct pinout compatibility.

Selection Notes

Select this component for full-duplex RS-485/RS-422 applications requiring 12Mbps transmission speeds. Ensure the design environment operates within the 0°C to +70°C temperature range. Verify that the system requires separate transmit and receive lines, as this differs from half-duplex alternatives like the MAX3485E. Check power supply constraints to confirm compatibility with the 3.0V to 3.6V input range.

Part Context

The MAX3491E belongs to the MAX3483E family of 3.3V low-power transceivers. Unlike the half-duplex MAX3485E, it provides full-duplex operation using a 14-pin package. It shares core features such as ±15kV ESD protection and fail-safe receivers with the broader family, offering a specialized solution for bidirectional communication needs in industrial and telecommunications sectors.

Replacement Considerations

MAX3490ESA: Full-duplex alternative in SO-14 package with identical electrical performance but different thermal characteristics and packaging.

FAQ

Does the MAX3491E require a charge pump for operation?

No, the device operates directly from a single +3.3V supply without requiring an internal or external charge pump.

What is the fail-safe feature of the receiver?

The receiver guarantees a logic-high output if both the A and B inputs are left open-circuit.

How does the MAX3491E differ from the MAX3485E?

The MAX3491E is a full-duplex transceiver with 14 pins, whereas the MAX3485E is a half-duplex transceiver with 8 pins.