Winbond Electronics Corporation W9751G6NB-25 TR

Overview

W9751G6NB-25 TR from Winbond is a 512Mbit (8M × 4 banks × 16-bit) DDR2 SDRAM compliant with JEDEC DDR2-800 (5-5-5 or 6-6-6) timing, operating at 1.8 V ± 0.1 V supply, supporting CAS Latency 3–7 and burst lengths of 4/8 for embedded memory subsystems in industrial control and networking equipment.

For engineers reviewing the W9751G6NB-25 TR datasheet, W9751G6NB-25 TR pinout, W9751G6NB-25 TR application, or W9751G6NB-25 TR equivalent, this page delivers verified DDR2-800 timing parameters, VFBGA-84 ball mapping, OCD/ODT configuration support, and validated industrial-grade alternatives for stable memory design-in.

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 data strobes (UDQS/LDQS). It supports posted CAS (AL = 0–2), programmable ODT termination per bank, and OCD impedance calibration for signal integrity optimization on high-speed PCB layouts.

Functional operation includes auto-precharge, self-refresh, and power-down modes (precharged/active), with command decoding governed by CS/RAS/CAS/WE and bank addressing via BA0–BA1. Refresh intervals are temperature-compensated (tREFI = 7.8 µs at ≤85°C; 3.9 µs at 95–105°C), and write latency is fixed as WL = RL − 1.

Key Specifications

Pinout & Package

VFBGA-84 package with 8×12.5 mm² footprint, 1.0 mm thickness, and ball pitch of 0.8 mm. Ball layout optimized for DDR2 signal integrity with dedicated VSSQ/VDDQ planes, isolated DLL power/ground (VDDL/VSSDL), and differential clock (CLK/CLK) and data strobe (UDQS/UDQS, LDQS/LDQS) pairs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MT47H64M16HR-25E and IS42S16400F-25BLI, the W9751G6NB-25 TR offers broader voltage tolerance, full EMR register support for advanced signal integrity tuning, and industrial temperature variants-making it optimal for ruggedized embedded systems requiring long-term supply stability and layout flexibility.

Availability

W9751G6NB-25 TR is available at Aetrix Electronics and suitable for industrial PLCs, network switches, medical imaging front-ends, and video surveillance encoders requiring stable component supply across extended product lifecycles.

Supply support for W9751G6NB-25 TR 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 W9751G6NB series belongs to Winbond's industrial-grade DDR2 SDRAM product line, engineered for reliable operation in harsh environments including factory automation, transportation infrastructure, and medical diagnostics equipment.

FAQ

What is the maximum supported CAS Latency for W9751G6NB-25 TR?

The W9751G6NB-25 TR supports programmable CAS Latency values of 3, 4, 5, 6, and 7. At DDR2-800 speed grade (-25), CL=3 and CL=4 are most commonly used to balance timing margin and performance. CL=5–7 are enabled for systems requiring relaxed setup/hold windows or operating under marginal signal integrity conditions. All CL settings are fully JEDEC-compliant and validated across the 0°C to 85°C temperature range.

Does W9751G6NB-25 TR support differential DQS operation?

Yes, the W9751G6NB-25 TR supports differential data strobe operation via UDQS/UDQS and LDQS/LDQS pairs. This mode is enabled by setting bit A10 in the Extended Mode Register 1 (EMR1) using an EMRS command. When enabled, both upper and lower byte strobes operate differentially, improving noise immunity and timing margin compared to single-ended mode-critical for high-density routing in industrial PCBs.

What is the purpose of the VSSDL and VDDL pins on W9751G6NB-25 TR?

VSSDL and VDDL are dedicated ground and power supply pins for the internal DLL (Delay Lock Loop) circuitry in the W9751G6NB-25 TR. Isolating DLL power/ground minimizes switching noise coupling into the timing path, ensuring stable DQ/DQS alignment across voltage and temperature. These pins must be decoupled with low-ESR capacitors close to the package and tied to the same 1.8 V supply as VDD/VDDQ, but routed on separate plane segments per Winbond layout guidelines.

Can W9751G6NB-25 TR operate at 105°C case temperature?

No, the W9751G6NB-25 TR is rated for 0°C ≤ TCASE ≤ 85°C only. For operation up to 105°C, Winbond offers the W9751G6NB-25J variant, which uses the same -25 speed grade but adds extended temperature qualification, doubled refresh rate (tREFI = 3.9 µs), and EMR2 configuration for high-temp self-refresh entry. The standard W9751G6NB-25 TR does not guarantee functionality or reliability beyond 85°C and must not be deployed in such environments.

How is On-Die Termination (ODT) controlled on W9751G6NB-25 TR?

ODT on the W9751G6NB-25 TR is controlled via the dedicated ODT pin (Ball K9), which must be driven HIGH to enable termination resistance on the DQ/DQS lines for the currently active bank. Termination value is configured through Extended Mode Register 1 (EMR1) bits A1–A0. ODT remains active only during reads/writes to the selected bank and automatically disables during precharge or idle states-reducing power consumption while maintaining signal integrity during active bursts.