Winbond Electronics Corporation W971GG6SB25I

Overview

W971GG6SB25I from Winbond is a 1G-bit DDR2 SDRAM organized as 8M × 8 banks × 16 bits, supporting DDR2-800 (5-5-5 or 6-6-6) operation at 400 MHz clock frequency with CL=5/6, tRCD=12.5 ns, and industrial temperature range (–40°C to +95°C). It delivers 1.6 Gb/s per pin in memory subsystems for networking processors and industrial controllers.

For engineers reviewing the W971GG6SB25I datasheet, W971GG6SB25I pinout, W971GG6SB25I application, or W971GG6SB25I equivalent, key selection criteria include its SSTL_18 interface compliance, on-die termination (ODT), OCD impedance calibration, differential clock inputs (CLK/CLK), and support for auto-precharge, self-refresh, and power-down modes in embedded memory designs.

Technical Context

This DDR2 SDRAM implements a double-data-rate architecture synchronized to differential CLK/CLK inputs, with bi-directional DQS/DQS strobes edge-aligned on reads and center-aligned on writes. Its DLL aligns DQ and DQS transitions to clock edges, enabling precise timing control at 400 MHz.

The device supports programmable CAS latency (CL=3–7), additive latency (AL=0–2), burst lengths of 4 or 8, and on-die termination controlled via ODT pin and EMR(1). It features off-chip driver (OCD) impedance adjustment using EMR(1) register settings and supports both posted CAS and write data mask (DM) functionality.

Key Specifications

Pinout & Package

W971GG6SB25I is packaged in an 84-ball WBGA (8 mm × 12.5 mm, 0.8 mm pitch), RoHS-compliant and lead-free. Ball layout follows JEDEC-standard DDR2 SDRAM footprint with dedicated VDDQ/VSSQ planes for I/O noise isolation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar DDR2 SDRAM applications.

Compared with MT47H128M8HQ-25E and IS42S16160F-25BLI, W971GG6SB25I uniquely combines industrial temperature rating, WBGA package, ODT control, and OCD calibration-enabling robust DDR2-800 implementation without external termination or layout compromises.

Availability

W971GG6SB25I is available at Aetrix Electronics and suitable for industrial automation, network infrastructure, and medical electronics requiring stable component supply with guaranteed long-term availability and extended temperature performance.

Supply support for W971GG6SB25I includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Winbond Electronics is a Taiwan-based semiconductor company specializing in specialty memory solutions, including NOR/NAND Flash, SRAM, and DRAM products for industrial, automotive, and communications markets.

W971GG6SB25I belongs to Winbond's DDR2 SDRAM product line, designed specifically for cost-sensitive, thermally demanding embedded systems requiring JEDEC-compliant DDR2-800 performance with industrial-grade reliability.

FAQ

What is the maximum operating frequency supported by W971GG6SB25I?

W971GG6SB25I supports DDR2-800 operation at 400 MHz clock frequency (800 MT/s data rate), compliant with JEDEC specification for 5-5-5 or 6-6-6 timing. It achieves this with CL=5 or CL=6, tRCD=12.5 ns, and tRP=12.5 ns under industrial temperature conditions (–40°C to +95°C).

Does W971GG6SB25I support on-die termination (ODT)?

Yes, W971GG6SB25I supports ODT via the dedicated ODT pin and EMR(1) register configuration. When ODT is asserted HIGH, internal termination resistors (typically 75 Ω or 150 Ω, configurable) are enabled on DQ/DQS lines to suppress reflections and improve signal integrity without external resistors.

What package type and ball count does W971GG6SB25I use?

W971GG6SB25I uses an 84-ball WBGA package measuring 8 mm × 12.5 mm with 0.8 mm pitch. This RoHS-compliant, lead-free package provides optimized thermal dissipation and board-level reliability for industrial applications requiring high-density memory placement.

How is the refresh interval managed at elevated temperatures for W971GG6SB25I?

At 85°C < TCASE ≤ 95°C, W971GG6SB25I requires tREFI = 3.9 µS (doubled refresh rate vs. standard 7.8 µS), achieved by setting A7=1 in EMR(2). This ensures data retention integrity across the full industrial temperature range without external controller modification beyond EMR programming.

Can W971GG6SB25I operate with single-ended DQS instead of differential DQS/DQS?

Yes - W971GG6SB25I supports both differential and single-ended DQS modes. Differential mode is enabled via EMR(1) bit A10; when disabled, single-ended DQS operation is used. Both modes maintain edge-aligned read and center-aligned write timing relative to DQS, preserving timing margin at 400 MHz.