ADM1485ARZ-REEL

Overview

The ADM1485ARZ-REEL is a high-speed, low-power EIA RS-485 transceiver manufactured by Analog Devices Inc. It operates from a single 5 V power supply and supports data rates up to 30 Mbps. The device features a driver propagation delay of 10 ns and a receiver propagation delay of 15 ns. It provides a bus common-mode range from -7 V to +12 V and includes thermal shutdown protection along with short-circuit protection for the driver outputs. The component is housed in an 8-Lead SOIC package and functions as a half-duplex transceiver.

Feature Summary

• Complies with EIA RS-485 standards for balanced data transmission on multipoint bus lines.
• Incorporates thermal shutdown circuitry that disables driver outputs when die temperature reaches 150°C.
• Features fail-safe receiver inputs that guarantee a logic high output state when inputs are unconnected.
• Maintains high-impedance driver outputs when disabled or powered down to minimize bus loading.

Applications

• Low Power RS-485 Systems
• DTE-DCE Interface
• Packet Switching
• Local Area Networks

Procurement Notes

Verify the specific ordering suffix against official documentation to confirm package type and reel configuration. Confirm RoHS compliance status and ensure the industrial temperature range variant matches system requirements. Cross-reference the manufacturer part number with authorized distributor catalogs to validate authenticity before procurement.

Selection Notes

Select this component for applications requiring bidirectional data communication on multipoint buses with high-speed capabilities. Ensure the design accommodates the single 5 V supply requirement and the specified common-mode voltage range. Verify that the 8-Lead SOIC package dimensions fit the available PCB space and that thermal management aligns with the device's dissipation characteristics.

Part Context

The ADM1485 series represents a line of differential line transceivers designed for robust communication in noisy environments. This specific model utilizes BiCMOS technology to combine low power consumption with fast switching speeds. It serves as a direct upgrade path for legacy components like the LTC1485 while maintaining compatibility with standard RS-485 network architectures.

Replacement Considerations

ADM1485JRZ

FAQ

What happens if the driver outputs are shorted?

The ADM1485 includes short-circuit protection that limits the output current. Additionally, thermal shutdown circuitry will disable the driver outputs if excessive power dissipation causes the die temperature to reach 150°C.

How does the receiver behave when inputs are floating?

The receiver contains a fail-safe feature that guarantees a logic high output state if the A and B inputs are unconnected or floating.

Can multiple ADM1485 devices be connected to the same bus?

Yes, up to 32 transceivers may be connected simultaneously on a bus, provided that only one driver is enabled at any given time to prevent contention.