UCC5621MWP

Overview

The UCC5621MWP is a 27-line active SCSI terminator designed for high-performance 5V systems. It operates within a supply voltage range of 4V to 7V and provides 110-ohm termination impedance trimmed to 5% accuracy. The device features split reverse disconnect logic, allowing independent control of lines 1–9 via DISCNCT2 and lines 10–27 via DISCNCT1. In disconnect mode, the supply current drops to approximately 100µA. Electrical characteristics include a maximum sourcing current of -900mA and a sinking current capability of +500mA. The package is a 44-pin QSOP (MWP).

Feature Summary

• Complies with SCSI, SCSI-2, SCSI-3, SPI, and FAST-20 standards.
• Features low channel capacitance of 2.5pF during disconnect to preserve signal integrity.
• Supports completely hot-pluggable operation with high impedance appearance when powered down.
• Includes internal thermal shutdown and current limit protection.

Applications

• High performance 5V SCSI parallel bus systems.
• FAST-20 (Ultra) SCSI implementations requiring optimized noise margins.
• Wide SCSI bus configurations utilizing split termination control.

Procurement Notes

Verify the specific MWP package variant against the latest Texas Instruments documentation before integration. Confirm that the application environment remains within the specified 0°C to 70°C operating temperature range. Ensure power supply rails strictly adhere to the 4V to 7V limits to prevent exceeding absolute maximum ratings. Validate that disconnect logic thresholds align with system control voltages.

Selection Notes

Select this component for designs requiring precise 110-ohm termination across 27 channels. The split disconnect feature is essential for managing power consumption in multi-node buses. Verify compatibility with SCSI-3 specifications regarding output current trimming. Consider the thermal resistance of the QSOP-44 package for heat dissipation requirements under full load conditions.

Part Context

This device belongs to the Unitrode family of terminators manufactured by Texas Instruments. It serves as an active termination solution replacing passive resistor networks. The MWP suffix indicates the 44-pin wide body QSOP package format. It addresses signal integrity issues common in high-speed parallel SCSI interfaces.

Replacement Considerations

UCC5631AMWP