DS21S07AE+T&R

Overview

The DS21S07AE+T&R is a SCSI terminator IC compliant with SCSI-1, Fast SCSI, and Ultra SCSI standards. It integrates a low-dropout voltage regulator and nine laser-trimmed 110Ω termination resistors with 2% tolerance into a monolithic device. The component operates within a 4.0V to 5.5V TERMPWR range and features an active-low power-down mode for bus isolation. It utilizes a 20-pin TSSOP package and supports hot-plug operations without affecting the SCSI bus.

Feature Summary

• Provides active termination for nine signal lines with enhanced noise immunity
• Integrates a low-dropout voltage regulator and precise switched termination resistors
• Supports actively negated SCSI signals and includes on-board thermal shutdown circuitry
• Enables electrical isolation from the SCSI bus via power-down mode

Applications

• Termination for single-ended drivers and receivers in SCSI systems
• Disk drive and RAID system components requiring hot-plug compatibility
• Peripheral devices acting as targets on a SCSI bus

Procurement Notes

Verify the specific suffix 'T&R' indicates tape-and-reel packaging when sourcing. Confirm lead-free status through the '+' designation. Check manufacturer documentation for current lifecycle status, as this component may be discontinued or subject to supply constraints. Ensure the 20-pin TSSOP footprint matches the target PCB design requirements.

Selection Notes

Select this component for designs requiring compliance with SCSI-1, Fast SCSI, and Ultra SCSI standards. It is suitable for applications needing active termination for nine signal lines with low quiescent current consumption. Consider the 20-pin TSSOP package size and the requirement for external decoupling capacitors on VREF and TERMPWR pins during integration.

Part Context

This part belongs to the DS21S07A family of SCSI terminators manufactured by Analog Devices Inc./Maxim Integrated. The family includes variants such as the DS21S07AS in a 16-pin SO package. These devices are designed to replace older passive termination methods, offering better performance in high-speed data transfer environments.

Replacement Considerations

The datasheet notes backward compatibility with the DS2107 and DS2107A. Designers should verify pinout and functional equivalence before substituting these legacy parts. No other direct substitute part numbers are explicitly confirmed in the provided documentation.