ADM1485ARMZ

Overview

The ADM1485ARMZ is a differential line transceiver designed for high-speed bidirectional data communication on multipoint bus transmission lines. It complies with EIA RS-485 and RS-422 standards, featuring a single driver and receiver within an 8-lead MSOP package. The device operates from a single 5 V supply and supports typical data rates of 30 Mbps. It provides a bus common-mode range from –7 V to +12 V. Key electrical parameters include a driver propagation delay of 10 ns and a receiver propagation delay of 15 ns. The component functions in half-duplex mode with three-state outputs and draws 2.2 mA during operation. It is rated for the industrial temperature range of -40°C to +85°C.

Feature Summary

• Thermal shutdown protection prevents damage by disabling driver outputs when internal die temperature reaches 150°C.
• Fail-safe receiver design ensures a logic high output state when inputs are unconnected or floating.
• High output impedance is maintained when disabled or powered down to minimize bus loading effects.
• BiCMOS fabrication process combines low power CMOS with fast switching bipolar technology.

Applications

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

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type and temperature rating. The 'ARMZ' designation indicates an 8-lead Mini Small Outline Package (MSOP) compliant with RoHS standards. Confirm that the required operating temperature range matches the industrial specification (-40°C to +85°C). Ensure compatibility with existing PCB footprints for the RM-8 package option before finalizing procurement.

Selection Notes

Select this component for applications requiring high-speed data transmission up to 30 Mbps on multipoint buses. It serves as a direct upgrade for legacy LTC1485 designs. Consider the MSOP package if space constraints exist on the printed circuit board. Verify that the system voltage aligns with the single 5 V supply requirement. Evaluate the need for thermal management given the short-circuit protection features.

Part Context

The ADM1485 belongs to the Analog Devices ADM1485 series of RS-485 transceivers. This family includes variants such as the ADM1486 for PROFIBUS applications and the ADM1487 with enhanced ESD protection. The ARMZ variant specifically utilizes the compact MSOP footprint, distinguishing it from the SOIC or PDIP options available in the broader product line.

Replacement Considerations

The datasheet identifies the ADM1485 as a superior upgrade for the LTC1485. No other specific substitute part numbers are documented in the provided source material.