Winbond Electronics Corporation W972GG8JB-3

Overview

W972GG8JB-3 from Winbond is a 2G-bit DDR2 SDRAM organized as 32M words × 8 banks × 8 bits, operating at DDR2-667 speed (5-5-5 timing), with 1.8 V ±0.1 V supply, SSTL_18 interface, and WBGA-60 package. It delivers 533 MT/s data rate per pin and supports CAS latencies of 3–7, burst lengths of 4/8, and on-die termination for signal integrity in memory subsystems of industrial embedded controllers.

For engineers reviewing the W972GG8JB-3 datasheet, W972GG8JB-3 pinout, W972GG8JB-3 application, or W972GG8JB-3 equivalent, this device requires attention to tRCD/tRP = 15 ns, ODT control via dedicated ball, OCD calibration sequence, and differential clock (CLK/CLK) synchronization - all critical for stable initialization and high-speed read/write timing compliance in DDR2 memory interfaces.

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 I/O referenced to both edges of DQS. It supports posted CAS (AL = 0–2), auto-precharge, and programmable write latency (WL = RL − 1).

Functional operation relies on mode register (MR) and extended mode registers (EMR1–EMR3) for configuring burst type, CAS latency, OCD impedance, ODT enable/disable, and DLL reset. Initialization mandates strict sequencing: stable power → 200 µs clock → CKE high → precharge all → EMRS(2)/EMRS(3)/DLL enable → MRS → OCD calibration.

Key Specifications

Pinout & Package

W972GG8JB-3 uses a 60-ball WBGA package (11 mm × 11.5 mm, RoHS-compliant, lead-free). Ball pitch is 0.8 mm; balls are arranged in a 9×7 staggered grid with corner blanks (NC) and dual-purpose pins (e.g., A10/AP, DM/RDQS).

Key Features

Applications

Equivalent & Alternatives

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

Compared with W972GG8JB-3, MT47H64M8CB-37E:H offers higher bandwidth but demands more stringent PCB layout and timing closure, while IS42S16400F-3BL trades density and advanced signal integrity features for lower gate count and legacy compatibility - making W972GG8JB-3 optimal for new industrial designs needing 2 G-bit capacity with integrated termination and calibration.

Availability

W972GG8JB-3 is available at Aetrix Electronics and suitable for industrial automation, network infrastructure, medical imaging, and automotive ADAS applications requiring stable component supply, long-lifecycle support, and guaranteed DDR2-667 timing compliance.

Supply support for W972GG8JB-3 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, flash, and logic ICs, with over 30 years of DRAM design heritage and ISO/TS 16949-certified manufacturing.

The W972GG8JB series belongs to Winbond's industrial-grade DDR2 SDRAM product line, engineered specifically for reliability-critical embedded systems requiring extended temperature tolerance, low-power refresh, and robust signal integrity features like ODT and OCD.

FAQ

What is the maximum supported CAS latency for W972GG8JB-3?

W972GG8JB-3 supports programmable CAS latency values of 3, 4, 5, 6, and 7. At its rated DDR2-667 speed grade (-3), CL=5 is the default and most commonly used setting, delivering optimal balance between access latency and timing margin. CL=3 is usable for lowest-latency applications but requires careful board-level signal integrity validation. All CL settings are configured via the Mode Register Set (MRS) command during initialization.

Does W972GG8JB-3 require external termination resistors?

No, W972GG8JB-3 does not require external termination resistors due to its integrated On-Die Termination (ODT) feature. The ODT function is controlled via the dedicated ODT ball and can be enabled to provide 75 Ω or 150 Ω termination on DQ and DQS lines. This eliminates the need for discrete parallel termination, reduces PCB component count, and improves signal integrity in point-to-point or fly-by DDR2 topologies.

What is the purpose of the DM/RDQS ball on W972GG8JB-3?

The DM/RDQS ball on W972GG8JB-3 serves a dual function: as DM (Data Mask) during write operations to suppress individual byte writes, or as RDQS (Read Data Strobe) when enabled via EMR(1)[A11]=1. When used as DM, it masks corresponding DQ bytes on both edges of DQS. When configured as RDQS, it provides an additional differential strobe for read data - improving timing margin in high-noise environments. Its mode is selected at initialization and cannot be changed dynamically.

Can W972GG8JB-3 operate with a single-ended clock instead of differential CLK/CLK?

No, W972GG8JB-3 requires differential CLK and CLK inputs as specified in JEDEC DDR2 standards. All command inputs are sampled at the crossing of CLK rising and CLK falling edges, and output data is referenced to both clock transitions. Using a single-ended clock violates the device's timing architecture and will result in undefined behavior or initialization failure. A differential clock generator or transformer is mandatory for compliant operation.

What is the minimum initialization sequence duration for W972GG8JB-3 before normal operation?

The minimum initialization sequence for W972GG8JB-3 requires ≥200 µs of stable clock after power stabilization, followed by ≥400 ns after CKE goes high before issuing the first PRECHARGE ALL command. Full initialization - including EMRS(2), EMRS(3), DLL enable, MRS, and OCD calibration - takes at least 200 clock cycles after DLL reset. Total elapsed time depends on clock frequency but typically exceeds 10 µs at 166 MHz; refer to Figure 1 in the datasheet for exact timing dependencies.