SN74SSTUB32864NMJR

Specialty Logic Overview

The SN74SSTUB32864NMJR is a 25-bit configurable register buffer manufactured by Texas Instruments. It operates with a supply voltage range of 1.7V to 1.9V and features SSTL_18 compliant outputs optimized for unterminated DIMM loads. The device supports differential clock inputs (CLK and CLK) and includes LVCMOS control inputs for reset and configuration. It provides low-power standby and active modes via dedicated control signals, ensuring glitch-free operation during power-up and reset transitions.

Specialty Logic Feature Summary

• Configurable as a 25-bit 1:1 or 14-bit 1:2 register buffer to support varying SDRAM load requirements on DIMMs.
• Outputs are edge-controlled and designed to meet SSTL_18 specifications for high-speed memory applications.
• Supports low-power standby mode by disabling differential input receivers when the reset signal is asserted.
• Includes active low-power mode controlled by DCS and CSR inputs to gate output states without stopping the clock.

Specialty Logic Applications

• DDR2 Registered DIMM (RDIMM) designs
• High-density memory module architectures requiring signal buffering
• Systems utilizing SSTL_18 I/O standards

Specialty Logic Procurement Notes

Verify the specific suffix NMJR against the manufacturer's current datasheet to confirm package type and tape-and-reel specifications. Ensure that the operating voltage constraints of 1.7V to 1.9V align with the target system's power delivery network. Confirm that the required reset and configuration pin hardwiring matches the final hardware design before procurement.

Specialty Logic Selection Notes

Select this component when designing DDR2 RDIMMs that require driving up to nine SDRAM loads per device in a 1:1 configuration. Choose the 1:2 configuration if the design requires driving eighteen loads using two devices per DIMM. Ensure the design can accommodate the requirement for differential clock inputs and that the C0 and C1 configuration pins can be hardwired to fixed logic levels.

Specialty Logic Part Context

This device belongs to the SN74SSTV family of buffers and line drivers from Texas Instruments. It is specifically engineered for memory interface applications, providing the necessary buffering and timing control for synchronous DRAM systems. The part integrates both data registration and output driving capabilities into a single compact package.

Specialty Logic Replacement Considerations

Public confirmed substitute part numbers only; omit otherwise.

Specialty Logic FAQ

How does the device handle reset during power-up?

To ensure defined outputs before stable clocks are provided, the RESET input must be held low during power-up. This clears the registers and forces outputs low, preventing glitches until the differential input receivers are fully enabled.

What is the function of the C0 and C1 inputs?

C1 controls the pin configuration between 25-bit 1:1 (low) and 14-bit 1:2 (high). C0 controls the pin configuration between Register A (low) and Register B (high) in the 1:2 arrangement. These should be hardwired and not switched during normal operation.