Winbond Electronics Corporation W971GG8KB25I

Overview

W971GG8KB25I from Winbond Electronics is a 1G-bit DDR2 SDRAM organized as 16M × 8 banks × 8 bits, operating at DDR2-800 speed (5-5-5 or 6-6-6 timing), with 1.8 V supply, SSTL_18 interface, and industrial temperature range (−40°C to +95°C). It supports CAS latency 3–7, burst lengths 4/8, on-die termination (ODT), and OCD impedance calibration for high-signal-integrity memory subsystems in embedded controllers and networking equipment.

For engineers reviewing the W971GG8KB25I datasheet, W971GG8KB25I pinout, W971GG8KB25I application, or W971GG8KB25I equivalent, key selection criteria include industrial-grade thermal reliability, DDR2-800 timing compliance, WBGA-60 package compatibility, and ODT/OCD configuration support for impedance-controlled PCB layouts.

Technical Context

This DDR2 SDRAM uses differential clock inputs (CLK/CLK) with input sampling at clock crossings, and source-synchronous DQS/DQS strobes edge-aligned on reads and center-aligned on writes. Its DLL aligns DQ and DQS transitions to the clock, enabling stable data capture at 400 MHz (DDR2-800).

Command decoding relies on synchronous control inputs (CS, RAS, CAS, WE, CKE) sampled on CLK edges, while address and bank select (A0–A13, BA0–BA2) define row/column/bank targeting. Extended Mode Registers (EMR1–EMR3) configure ODT states, OCD calibration, additive latency, and differential strobe modes.

Key Specifications

Pinout & Package

W971GG8KB25I is housed in a 60-ball Wafer-Level Ball Grid Array (WBGA) package measuring 8 mm × 12.5 mm with 0.8 mm ball pitch. The package uses lead-free materials and complies with RoHS directives.

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, W971GG8KB25I offers identical DDR2-800 timing and industrial temperature range in a pin-compatible WBGA-60 footprint, enabling direct substitution where Winbond's qualification and sourcing continuity are preferred.

Availability

W971GG8KB25I is available at Aetrix Electronics and suitable for industrial automation, network infrastructure, medical imaging, and automotive ADAS applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for W971GG8KB25I 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 manufacturer specializing in specialty memory solutions including NOR/NAND Flash, SRAM, and DRAM products for industrial, communications, and consumer markets.

The W971GG8KB series targets cost-sensitive, thermally demanding embedded systems requiring JEDEC-compliant DDR2 memory with industrial-grade reliability and simplified power delivery (single 1.8 V supply for core/I/O/DLL).

FAQ

What is the maximum supported CAS latency for W971GG8KB25I?

W971GG8KB25I supports programmable CAS latency values of 3, 4, 5, 6, and 7. At DDR2-800 speed grade (−25/25I), CL=5 corresponds to a minimum tCK of 2.5 ns, and CL=6 to 2.5 ns minimum - both are fully supported per the device's AC timing specifications and mode register configuration.

Does W971GG8KB25I require external termination resistors?

No, W971GG8KB25I integrates On-Die Termination (ODT) on DQ and DQS pins, configurable via EMR(1). When ODT is enabled (ODT pin HIGH), internal termination resistors eliminate the need for external parallel resistors, simplifying PCB layout and improving signal integrity on high-speed memory buses.

What is the purpose of the DM/RDQS pin on W971GG8KB25I?

The DM/RDQS pin on W971GG8KB25I serves dual functions: as DM (Data Mask) during write operations to suppress individual byte lanes, and as RDQS (Read Data Strobe) when enabled via EMR(1)[A11]. In differential strobe mode, it pairs with DQS to provide enhanced timing margin for read data capture.

Can W971GG8KB25I operate without OCD calibration?

Yes, W971GG8KB25I can operate without OCD calibration by programming EMR(1) with default settings (A9=A8=A7=HIGH then LOW). However, performing OCD calibration during initialization optimizes output driver impedance matching across voltage and temperature, improving signal fidelity in high-density layouts.

Is W971GG8KB25I compatible with standard DDR2-800 controllers?

Yes, W971GG8KB25I is fully JEDEC-compliant for DDR2-800 (5-5-5 and 6-6-6 timing), supports all standard DDR2 commands (ACT, READ, WRITE, PRE, REF, MRS, EMRS), and interfaces using SSTL_18 signaling - ensuring drop-in compatibility with any controller designed for DDR2-800 SDRAM.