DS21T07E+

Overview

The DS21T07E+ is a SCSI terminator integrated circuit manufactured by Analog Devices Inc./Maxim Integrated, housed in a 20-pin TSSOP package. It provides active termination for nine signal lines compliant with SCSI-1, Fast SCSI, and Ultra SCSI standards. The device integrates laser-trimmed 110 ohms termination resistors with 2% tolerance and a low dropout voltage regulator. Operating conditions specify a TERMPWR voltage range of 4.00V to 5.50V and an operating temperature range of 0°C to 70°C. In power-down mode, the current consumption drops to approximately 150 µA.

Feature Summary

• Fully compliant with SCSI-1, Fast SCSI, and Ultra SCSI standards
• Integrates nine precise switched 110 ohms termination resistors
• Includes onboard thermal shutdown circuitry
• Supports SCSI bus hot-plug operations via power-down isolation

Applications

• Active termination for SCSI cable segments
• Termination for disk drives in RAID systems
• Peripheral target devices on SCSI buses

Procurement Notes

Verify component authenticity through authorized distributors or direct manufacturer channels. Confirm RoHS compliance status and check for specific environmental declarations such as REACH material reports. Ensure the ordering suffix matches the required package type and that the part meets all applicable regulatory standards for the intended deployment region.

Selection Notes

Select the DS21T07E+ variant specifically for designs requiring a 20-pin Thin Shrink Small Outline Package (TSSOP). Verify that the system architecture utilizes single-ended drivers and receivers compatible with this active termination solution. Ensure adequate decoupling capacitors are included in the design to support the internal regulator and maintain signal integrity across the SCSI bus.

Part Context

This component belongs to the DS21T07 family of SCSI terminators produced by Analog Devices Inc./Maxim Integrated. It serves as a successor to earlier models like the DS2107 and DS21S07, offering backward compatibility while supporting modern high-speed SCSI standards. The E suffix denotes the 20-pin TSSOP package configuration.

Replacement Considerations

The datasheet confirms electrical compatibility with the DS2107, DS2107A, and DS21S07. Designers may consider these parts as functional substitutes if package constraints allow, provided the pinout differences between SOIC and TSSOP formats are addressed in the PCB layout.