LTC1685IS8#TRPBF

Drivers, Receivers, Transceivers Overview

The LTC1685IS8#TRPBF is a high-speed, precision delay RS485/RS422 transceiver operating at data rates up to 52Mbps. It features tightly controlled propagation delays of 13ns to 25ns and low skew of 500ps over the industrial temperature range (-40°C to 85°C). The device operates from a single 5V supply with a typical current draw of 7mA. It includes fail-safe receiver operation across a -7V to 12V common mode range, short-circuit protection, and thermal shutdown. Packaged in an 8-lead plastic SO (S8) surface-mount format.

Drivers, Receivers, Transceivers Feature Summary

• Precision timing architecture ensures stable propagation delay and minimal skew across wide temperature and common mode voltage ranges.
• Integrated fail-safe mechanism guarantees a logic high output when inputs are open or shorted within the full common mode range.
• Robust protection features include driver and receiver short-circuit detection with current limiting, plus thermal shutdown circuitry.

Drivers, Receivers, Transceivers Applications

• High-speed backplane point-to-point transceivers
• Fast-20 and Fast-40 High Voltage Differential SCSI systems
• STS-1/OC-1 data transmission links

Drivers, Receivers, Transceivers Procurement Notes

Verify that the specific suffix #TRPBF corresponds to tape and reel packaging as indicated by standard Analog Devices conventions for this part number. Confirm the 'I' grade designation matches the required -40°C to 85°C operating temperature range for your application environment before finalizing orders.

Drivers, Receivers, Transceivers Selection Notes

Select this component when precise timing synchronization is critical for high-speed differential signaling. It serves as a pin-compatible alternative to the LTC485 while offering significantly higher data rate capabilities. Ensure the system design accommodates the 5V supply requirement and utilizes proper series termination for backplane applications.

Drivers, Receivers, Transceivers Part Context

This part belongs to the Linear Technology family of high-speed RS485 transceivers. It is designed to meet RS422 requirements alongside RS485 standards. The device is functionally compatible with legacy parts like the LTC485 but provides enhanced speed and timing precision suitable for demanding industrial and communication interfaces.

Drivers, Receivers, Transceivers Replacement Considerations

The datasheet lists the LTC1485 as a pin-compatible alternative with lower 10Mbps speed. For quad-channel configurations, consider the LTC1518/LTC1519 receivers or LTC1688/LTC1689 drivers. Full-duplex requirements may necessitate the LTC1686 or LTC1687 models instead.

Drivers, Receivers, Transceivers FAQ

How does the device handle input faults?

The receiver features a fail-safe design that guarantees a logic high output state when the A and B inputs are left open or shorted together, preventing false data pulses during line faults.

What is the impact of power-up on short-circuit protection?

If powered up with outputs enabled into DC-biased terminations, the device may enter short-circuit mode. The DE pin must be held low for at least 200ns after power-up or fault removal to resume normal operation.

Can the DI input accept CMOS levels?

Yes, the Driver Input (DI) can be driven by 0V to 5V CMOS levels while maintaining operation up to 40Mbps, though duty cycle distortion may slightly increase compared to lower voltage swings.