UCC5640PW28TR

Overview

The UCC5640PW28TR is an active low-voltage differential (LVD) SCSI terminator manufactured by Texas Instruments. It operates within a TRMPWR voltage range of 2.7 V to 5.25 V and supports Ultra2, Ultra3, Ultra160, and Ultra320 standards. The device provides a differential impedance of 105 Ω and a common-mode impedance of 150 Ω. It features a 1.25 V regulator with source/sink currents up to 100 mA and a 1.3 V regulator for the DIFSENS line. The package is a 28-pin TSSOP (PW), available in tape-and-reel quantities of 2,000.

Feature Summary

• Active Y-terminator design optimized for LVD SCSI bus performance
• Automatic detection and disconnection from SE or HVD drivers
• Low channel capacitance to minimize bus loading

Applications

• SCSI SPI-2 Ultra2 (Fast-40) systems
• SCSI SPI-3 Ultra3 / Ultra160 (Fast-80) systems
• SCSI SPI-4 Ultra320 (Fast-160) systems

Procurement Notes

Verify the specific ordering suffix 'TR' indicates the tape-and-reel packaging format containing 2,000 units per reel. Confirm the package type matches the 28-pin TSSOP designation required for the target application layout. Ensure the operating temperature range aligns with the commercial rating of 0°C to 70°C.

Selection Notes

Select this component specifically for low-voltage differential SCSI implementations requiring automatic mode switching. Do not use in single-ended or high-voltage differential environments as the device will enter a high-impedance state. Consider the 28-pin package availability if additional control pins like LVD status are needed compared to the 24-pin variant.

Part Context

This part belongs to the UCC5640 family of active terminators designed for SCSI bus applications. The 'TR' suffix denotes the tape-and-reel packaging option, while 'PW' identifies the 28-pin TSSOP physical package. It serves as a migration path for improving SCSI system standards while maintaining compatibility with legacy specifications.

Replacement Considerations

The UCC5640PW24TR is the primary alternative within the same family, offering identical electrical characteristics but utilizing a 24-pin TSSOP package instead of the 28-pin version.