LTC1484IS8#PBF

Drivers, Receivers, Transceivers Overview

The LTC1484IS8#PBF is a low power RS-485 transceiver manufactured by Analog Devices Inc. It operates on a single 5V supply with a voltage range of 4.75V to 5.25V. The device features one driver and one receiver, supporting data rates up to 5 Mbps. Supply current is 900µA maximum when the driver is enabled and 700µA maximum when disabled. Shutdown mode draws 20µA maximum. It includes receiver fail-safe for floating or shorted inputs and withstands –15kV ESD (HBM). Operating temperature ranges from -40°C to 85°C. The component is housed in an 8-lead SOIC package.

Drivers, Receivers, Transceivers Feature Summary

• Fail-safe receiver guarantees a high output state when inputs are open, shorted, or terminated without a signal.
• Enhanced ESD protection withstands –15kV human body model and IEC-1000-4-2 levels without latchup.
• Thermal shutdown circuit forces outputs to high impedance during excessive power dissipation or faults.
• Power-up and power-down glitch-free driver outputs prevent bus contention.

Drivers, Receivers, Transceivers Applications

• Battery-powered RS-485/RS-422 communication systems
• Level translation between different logic families
• Carrier Detect Multiple Access (CDMA) networks

Drivers, Receivers, Transceivers Procurement Notes

Verify the specific suffix #PBF indicates lead-free compliance and RoHS adherence. Confirm the IS8 designation corresponds to the industrial temperature range (-40°C to 85°C) and the SOIC-8 package type. Ensure the source document matches the official Analog Devices datasheet for the LTC1484 series to validate electrical parameters.

Drivers, Receivers, Transceivers Selection Notes

Select this component for applications requiring low quiescent current and robust fault protection on RS-485 buses. The integrated fail-safe feature eliminates the need for external pull-up resistors in many configurations. Verify that the 5V supply requirement aligns with the system design and that the 5 Mbps data rate meets the application's throughput needs.

Drivers, Receivers, Transceivers Part Context

This part belongs to the LTC1484 family of low power RS-485 transceivers. It is pin-compatible with the older LTC485 model, facilitating direct upgrades. The 'I' suffix denotes the industrial temperature grade, while 'S8' specifies the plastic SOIC package variant within the broader product line.

Drivers, Receivers, Transceivers Replacement Considerations

The LTC1484 is explicitly noted as pin compatible with the LTC485. Designers should verify that the replacement maintains the same fail-safe behavior and ESD protection levels required by the original circuit design.

Drivers, Receivers, Transceivers FAQ

How does the receiver fail-safe mechanism function?

The receiver guarantees a high output state when the A and B inputs are left open, shorted together, or terminated with no signal present, eliminating the need for external components to ensure this state.

What is the ESD protection rating for the A and B pins?

The A and B pins withstand –15kV using the Human Body Model, as well as IEC-1000-4-2 Level 4 (–8kV) contact and Level 3 (–8kV) air discharge specifications without damage or latchup.

What triggers the thermal shutdown circuit?

The thermal shutdown circuit activates if the die temperature rises above 150°C due to prolonged shorts at the driver outputs, forcing the outputs into a high impedance state until the temperature cools to approximately 130°C.