ADM1485ARZ-REEL7

Overview

The ADM1485ARZ-REEL7 is a 5 V low power EIA RS-485 transceiver fabricated on high-speed, low power BiCMOS technology. It features one driver and one receiver with independent enable controls. The device supports data rates up to 30 Mbps and operates from a single 5 V supply. It provides a bus common-mode range of -7 V to +12 V. Driver propagation delay is typically 10 ns, while receiver propagation delay is typically 15 ns. Operating temperature range is -40°C to +85°C. Supply current is 2.2 mA when enabled and 1 mA when disabled. The component is housed in an 8-lead SOIC package.

Feature Summary

• Thermal shutdown protection prevents damage during excessive power dissipation or output shorting by forcing the driver into a high impedance state.
• Fail-safe receiver design ensures a logic high output state when inputs are unconnected or floating.
• High output impedance is maintained for both driver and receiver outputs when powered down or disabled, minimizing bus loading effects.

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 temperature rating. Confirm RoHS compliance status through manufacturer datasheets. Ensure the procurement channel sources directly from authorized distributors to guarantee component authenticity and traceability.

Selection Notes

Select this component for multipoint bus transmission lines requiring bidirectional data communication. It is suitable for applications needing high-speed data rates up to 30 Mbps with low power consumption. Verify that the system voltage matches the required 5 V supply and that the environmental conditions fall within the specified industrial temperature range.

Part Context

This part belongs to the ADM1485 series of differential line transceivers designed for balanced data transmission. It complies with RS-485 and RS-422 EIA standards. The series includes variants with different packaging options such as PDIP and MSOP, catering to various board space and thermal requirements.

Replacement Considerations

The datasheet identifies the LTC1485 as a predecessor. Verify pin compatibility and electrical specifications before substituting with other RS-485 transceivers from different manufacturers.

FAQ

What happens if the driver outputs are shorted?

The thermal shutdown circuitry detects increased die temperature and disables the driver outputs to prevent damage. The drivers re-enable once the temperature drops below the threshold.

How many transceivers can be connected on a single bus?

Up to 32 transceivers may be connected simultaneously on a bus, provided only one driver is enabled at any given time.

What is the fail-safe feature of the receiver?

The receiver guarantees a logic high output state if the inputs are open circuit or floating, ensuring a defined state during idle conditions.