Winbond Electronics Corporation W971GG6KB25I

Overview

W971GG6KB25I from Winbond Electronics 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 1.8 V supply, with CAS latency options of 3–7 and burst lengths of 4 or 8. It delivers up to 800 Mb/sec/pin data transfer in industrial temperature range (−40°C to +95°C), used in embedded networking and industrial control memory subsystems.

For engineers reviewing the W971GG6KB25I datasheet, W971GG6KB25I pinout, W971GG6KB25I application, or W971GG6KB25I equivalent, key selection considerations include its industrial-grade thermal rating, on-die termination (ODT), off-chip driver (OCD) impedance calibration, differential clock interface (CLK/CLK), and SSTL_18 I/O compatibility for signal integrity in high-speed memory bus designs.

Technical Context

This DDR2 SDRAM implements a double-data-rate architecture synchronized to differential CLK/CLK inputs, with DLL-aligned DQ/DQS timing and source-synchronous read/write strobes (UDQS/LDQS). It supports programmable additive latency (AL = 0–2), enabling posted CAS for improved command bus efficiency.

Functional operation includes auto-precharge, self-refresh, and power-down modes (precharged and active), with ODT configurable via EMR(1) and OCD calibration supported through extended mode register commands. All control/address inputs are sampled on the crossing of CLK rising and CLK falling edges.

Key Specifications

Pinout & Package

W971GG6KB25I is packaged in an 84-ball WBGA (8 mm × 12.5 mm, RoHS-compliant, lead-free).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MT47H128M16HR-25E and IS42S16160F-25BLI, W971GG6KB25I uniquely combines industrial temperature qualification, WBGA packaging for high-density layouts, and full OCD/ODT configurability - making it the preferred choice for ruggedized, thermally demanding DDR2 memory subsystems where long-term reliability and signal fidelity are non-negotiable.

Availability

W971GG6KB25I is available at Aetrix Electronics and suitable for industrial automation, network infrastructure, and medical imaging systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for W971GG6KB25I 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.

W971GG6KB25I belongs to Winbond's DDR2 SDRAM product line, designed specifically for cost-sensitive yet thermally demanding embedded applications requiring JEDEC-compliant 1.8 V memory with robust signal integrity features.

FAQ

What is the maximum clock frequency supported by W971GG6KB25I?

W971GG6KB25I supports DDR2-800 operation, meaning a maximum input clock frequency of 400 MHz. This yields an effective data transfer rate of 800 Mt/s (megatransfers per second) due to double-data-rate architecture. The device meets JEDEC timing specifications for tCK = 2.5 ns (min) at CL = 5 and tCK = 2.5 ns (min) at CL = 6, validated across the full −40°C to +95°C case temperature range.

Does W971GG6KB25I require external termination resistors?

No - W971GG6KB25I integrates On-Die Termination (ODT) controlled via the ODT pin and extended mode registers. When ODT is asserted HIGH, internal termination resistors (typically 75 Ω or 150 Ω, configurable) are enabled on DQ and DQS lines, eliminating the need for discrete parallel termination and reducing PCB routing complexity and signal reflection.

How does the OCD calibration feature improve signal integrity in W971GG6KB25I?

OCD calibration in W971GG6KB25I dynamically adjusts the output driver impedance to match the PCB trace characteristic impedance (e.g., 50 Ω single-ended). By executing OCD calibration during initialization (per datasheet flow), W971GG6KB25I minimizes overshoot/undershoot on write data edges - critical for maintaining eye opening and timing margin at 400 MHz clock rates.

Can W971GG6KB25I operate with a single-ended clock instead of differential CLK/CLK?

No - W971GG6KB25I requires differential clock inputs (CLK and CLK) as specified in JEDEC DDR2 standard. All address and command inputs are sampled at the crossing of CLK rising and CLK falling edges. Using single-ended clocking violates timing specifications and will result in undefined behavior or initialization failure.

What is the purpose of the A10/AP pin on W971GG6KB25I?

On W971GG6KB25I, pin A10 functions as the Auto-Precharge (AP) bit during READ and WRITE commands. When A10 is driven HIGH during a burst access, the memory automatically issues a PRECHARGE command to the accessed bank upon burst completion - eliminating the need for a separate PRECHARGE instruction and improving sequential access efficiency.