DS21S07AE+

Overview

The DS21S07AE+ 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 die. The device operates on a 5V supply within a 4.00V to 5.50V range and functions in temperatures from 0°C to +70°C. Packaged in a 20-pin TSSOP, it provides active termination for nine signal lines, featuring intrinsic TERMPWR decoupling and a power-down mode that electrically isolates the termination resistors from the bus.

Feature Summary

• Fully compliant with SCSI-1, Fast SCSI, and Ultra SCSI standards
• Integrates a low-dropout voltage regulator and nine precise switched 110Ω termination resistors
• Power-down mode isolates termination resistors from the bus for hot plug compatibility
• Includes on-board thermal shutdown circuitry

Applications

• Termination at both ends of cable segments in SCSI systems with single-ended drivers and receivers
• Embedded disk drives requiring SCSI bus termination
• RAID system components acting as targets on a SCSI bus

Procurement Notes

Verify the component designation against official manufacturer documentation to confirm specifications. Ensure the package type matches the required footprint, specifically the 20-pin TSSOP configuration for this model. Cross-reference the datasheet revision and electrical characteristics to validate compatibility with existing system designs before procurement.

Selection Notes

Select this component for applications requiring active termination compliant with SCSI-1, Fast SCSI, and Ultra SCSI standards. The device supports backward compatibility with earlier models like the DS2107. Consider the 20-pin TSSOP package size and the requirement for external decoupling capacitors when designing the PCB layout for optimal performance.

Part Context

The DS21S07A series belongs to the family of SCSI interface integrated circuits designed by Analog Devices / Maxim Integrated. This specific part number represents the 20-pin Thin Shrink Small Outline Package (TSSOP) variant. The '+' suffix indicates a lead-free package version, which includes a corresponding mark on the top surface of the device.

Replacement Considerations

The DS21S07AS is a pin-compatible alternative available in a 16-pin SO package.