LTC490IN8#PBF

Drivers, Receivers, Transceivers Overview

The LTC490IN8#PBF is a low-power differential bus transceiver designed for multipoint data transmission in RS-485 and RS-422 applications. It operates on a single 5V supply with a typical supply current of 300mA. The device features an extended common mode range from -7V to 12V, allowing up to a -7V ground difference between devices. It includes thermal shutdown protection and glitch-free driver outputs for live insertion. The receiver provides fail-safe functionality with 70mV hysteresis. Driver propagation delays are typically 28ns with 5ns skew, supporting 2.5MB operation. The part is housed in an 8-lead PDIP package.

Drivers, Receivers, Transceivers Feature Summary

• Low power CMOS design offering significant savings over bipolar counterparts while maintaining ruggedness against overload and ESD damage.
• Thermal shutdown circuit prevents excessive power dissipation by forcing driver outputs into a high impedance state during faults.
• Receiver incorporates a fail-safe feature that guarantees a high output state when inputs are left open.
• Power-up and power-down glitch-free driver outputs permit the live insertion or removal of packages without data corruption.

Drivers, Receivers, Transceivers Applications

• Multipoint data transmission systems adhering to RS-485 standards.
• Full-duplex communication links utilizing twisted-pair wiring as defined by RS-422 specifications.
• Line repeater configurations for extending cable lengths beyond standard limits.

Drivers, Receivers, Transceivers Procurement Notes

Verify the specific ordering suffix to confirm the package type and temperature rating. The 'I' designation indicates an industrial temperature range of -40°C to 85°C. Ensure the '#PBF' suffix is present to guarantee lead-free compliance and RoHS adherence. Cross-reference the manufacturer's latest documentation to confirm current production status and any potential pinout variations before finalizing procurement orders.

Drivers, Receivers, Transceivers Selection Notes

Select this component for applications requiring a single 5V supply and extended common mode voltage tolerance. It serves as a direct pin-compatible replacement for the SN75179 in existing designs. Consider the 2.5MB maximum data rate and 32-transceiver bus limit when designing network topologies. Evaluate the need for thermal protection and fail-safe receiver behavior in noisy industrial environments.

Drivers, Receivers, Transceivers Part Context

This device belongs to the LTC490 family of low-power differential transceivers manufactured by Analog Devices Inc. (formerly Linear Technology). The family includes variants such as the LTC490C for commercial temperatures and the LTC491 which adds a shutdown control pin. These components are widely used in industrial automation and building control networks requiring reliable half-duplex communication.

Drivers, Receivers, Transceivers Replacement Considerations

The LTC490 is explicitly documented as pin-compatible with the SN75179. For higher speed requirements, the LTC1686/LTC1687 series offers 52Mbps performance while maintaining pin compatibility. Designers should verify that substitute parts meet the specific -7V to 12V common mode range and thermal shutdown thresholds required by the original application.