UCC5630AMWPTRG4

Overview

The UCC5630AMWPTRG4 is a multimode SCSI terminator designed for SPI-2, SPI-3, and SPI-4 bus architectures. It automatically senses the bus via the DIFFB pin to switch between single-ended (SE) and low voltage differential (LVD) termination modes. The device operates on a TRMPWR supply ranging from 2.7V to 5.25V. In LVD mode, the REG output provides a typical voltage of 1.25V with a short-circuit source current of -420mA and sink current of 180mA. Differential impedance is typically 105 ohms with a bias voltage of 125mV. SE mode features an impedance of 110 ohms and termination currents between -18mA and -25.4mA depending on signal level. The component is housed in a 36-pin SSOP package.

Feature Summary

• Automatically detects and switches between single-ended and low voltage differential SCSI termination modes based on bus signals.
• Integrated differential failsafe biasing ensures signal integrity across various operating conditions.
• Includes thermal packaging with heat sink ground pins to minimize junction temperature and improve reliability.
• Supports active negation and master/slave input configurations for multi-device bus setups.

Applications

• Termination for Ultra2 (SPI-2), Ultra3 (SPI-3), and Ultra320 (SPI-4) SCSI parallel interfaces
• Multi-mode active termination where single-ended and low voltage differential devices coexist on the same bus
• High-performance storage systems requiring compliant termination for data lines and control lines

Procurement Notes

Verify that the ordering suffix matches the required package type and environmental compliance. The 'MWP' designation indicates a 36-pin SSOP package, while 'TRG4' specifies tape and reel packaging with lead-free and halogen-free materials. Confirm the temperature range requirement aligns with the commercial grade specification of 0°C to 70°C before finalizing procurement orders.

Selection Notes

Select this component when designing SCSI terminators that must support mixed legacy single-ended and modern low voltage differential devices without manual configuration. Ensure the design accommodates the specific capacitance balance requirements of SPI standards. Verify that the power supply voltage remains within the 2.7V to 5.25V range to maintain proper regulator operation and termination accuracy.

Part Context

This part belongs to the UCC5630A family of multimode SCSI terminators manufactured by Texas Instruments. It serves as a critical interface component for maintaining signal integrity in high-speed parallel SCSI environments. The device integrates multiple termination networks into a single monolithic solution, simplifying board layout compared to discrete implementations.

Replacement Considerations

The UCC5630AFQP is a compatible alternative offering the same functionality in a 48-pin LQFP package. When substituting, verify pinout compatibility or implement necessary adapter circuitry due to the different physical footprint and pin assignments between the SSOP and LQFP packages.

FAQ

How does the UCC5630AMWPTRG4 determine which termination mode to use?

The device monitors the DIFSENS line voltage through the DIFFB input pin. If the voltage is below 0.5V, it selects single-ended mode. Between 0.7V and 1.9V, it switches to low voltage differential mode. Above 2.4V, it enters a high impedance state to disconnect from high voltage differential buses.

What is the purpose of the MSTR/SLV pin?

The MSTR/SLV pin controls the DIFSENS driver. When connected to TRMPWR, it enables the driver, allowing the device to act as a master. When grounded, it disables the driver, configuring the device as a slave. This allows multiple terminators to share the bus while only one drives the sense line.

Why are HS/GND pins included in the package?

The HS/GND pins serve as heat sink grounds directly connected to the die mount paddle. They conduct heat away from the die to reduce junction temperature, which is essential for managing power dissipation, particularly in single-ended mode where instantaneous power per line can be significant.