DS2125+

Overview

The DS2125+ is an Ultra3 LVD/SE SCSI terminator manufactured by Dallas Semiconductor. It provides active termination for fifteen signal lines with a nominal impedance of 110 ohms. The device supports both low-voltage differential and single-ended modes, enabling multimode operation within SCSI systems. It features onboard thermal shutdown circuitry and a power-down mode to isolate termination resistors from the bus. The component is designed for high-volume applications and ensures compliance with Ultra SCSI standards.

Feature Summary

• Supports multimode operation for both low-voltage differential and single-ended SCSI signals
• Provides active termination for fifteen signal lines with laser-trimmed 110-ohm resistance
• Includes onboard thermal shutdown circuitry for protection
• Features a power-down mode that isolates termination resistors from the bus

Applications

• Ultra3 LVD SCSI system terminations
• Single-ended SCSI system terminations
• High-volume electronic design applications requiring compliant active termination

Procurement Notes

Verify the manufacturer designation as Dallas Semiconductor or Maxim Integrated Products, as corporate transitions occurred. Confirm the suffix '+' indicates lead-free and RoHS compliance status. Ensure the part number matches the specific 15-line configuration rather than other variants in the family. Cross-reference official datasheets to confirm pinout and package details before procurement.

Selection Notes

Select this component when designing systems requiring simultaneous support for LVD and SE SCSI modes. The 15-line capacity distinguishes it from lower-capacity terminators like the DS2105. Consider the onboard thermal protection and power-down isolation features for robust system reliability. Verify compatibility with Ultra3 standards during the selection process.

Part Context

The DS2125+ belongs to the Dallas Semiconductor SCSI terminator family, which includes parts like the DS2105 and DS21S07A. These components are designed to provide active termination for SCSI cables, offering benefits such as enhanced noise immunity and low quiescent current consumption compared to passive solutions. The series supports various SCSI generations including Fast and Ultra SCSI.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.