SSTU32866EC/G,551

Specialty Logic Overview

The SSTU32866EC/G,551 is a 1.8 V configurable registered buffer designed for DDR2 memory modules requiring parity checking. It supports two topologies: a 25-bit 1:1 mode or a 14-bit 1:2 mode, selectable via configuration pins C0 and C1. In the 1:2 configuration, it functions as Register A or B on the DIMM. The device accepts a parity bit from the memory controller, compares it with data inputs, and indicates errors via an open-drain QERR pin using even parity convention. It operates up to 450 MHz clock frequency with single-bit switching propagation delay of 1.8 ns max and mass-switching delay of 2.0 ns max. Packaged in a 96-ball LFBGA.

Specialty Logic Feature Summary

• Configurable register supporting DDR2 Registered DIMM applications with selectable 25-bit 1:1 or 14-bit 1:2 modes
• Integrated parity checking function that compares input parity bits with data inputs to detect errors
• Controlled output impedance drivers enable optimal signal integrity and speed performance
• Supports differential clock inputs and LVCMOS switching levels on control and reset inputs

Specialty Logic Applications

• DDR2 registered DIMMs desiring parity checking functionality

Specialty Logic Procurement Notes

Verify the specific ordering suffix matches the required solder ball compound. The EC/G suffix indicates Pb-free (SnAgCu) solder balls, while EC denotes SnPb solder balls. Confirm the package version corresponds to SOT536-1. Ensure the operating temperature range meets system requirements, specified as 0 °C to +70 °C. Cross-reference the datasheet revision to ensure compatibility with current design specifications.

Specialty Logic Selection Notes

Select this component when designing DDR2 RDIMMs that require hardware-based parity error detection. Choose the 1:1 configuration for standard single-register setups or the 1:2 configuration for high-density designs requiring cascaded parity processing. Ensure the system provides stable 1.8 V supply and differential clock signals. Verify that the memory controller can supply the necessary parity input bit and handle the active-low error output signaling correctly.

Specialty Logic Part Context

This device is part of NXP's DDR2 registered buffer family, specifically engineered to comply with JEDEC JESD82-7 standards for registered buffers while adding parity capabilities. It serves as a critical interface component between memory controllers and DRAM chips on registered dual in-line memory modules. The inclusion of parity checking enhances data integrity for enterprise and server-grade memory applications where error detection is mandatory.

Specialty Logic Replacement Considerations

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