Winbond Electronics Corporation W631GG8NB-15

Overview

W631GG8NB-15 from Winbond is a 1G-bit DDR3 SDRAM organized as 16M × 8 banks × 8 bits, compliant with DDR3-1333 (9-9-9) timing, operating at 667 MHz with VDD/VDDQ = 1.5 V ± 0.075 V, and packaged in a RoHS-compliant 78-ball VFBGA (8 mm × 10.5 mm). It supports programmable CAS Latency (CL = 5–10), CAS Write Latency (CWL = 5–7), on-die termination (ODT), ZQ calibration, and asynchronous RESET# for power-up initialization in embedded computing and industrial control memory subsystems.

For engineers reviewing the W631GG8NB-15 datasheet, W631GG8NB-15 pinout, W631GG8NB-15 application, or W631GG8NB-15 equivalent, key selection considerations include its DDR3-1333 speed bin, industrial-grade 0°C to 95°C case temperature range, SSTL_15 interface compliance, 8-bank concurrency, and support for dynamic ODT, write leveling, and partial array self-refresh (PASR) in space-constrained, thermally stable memory designs.

Technical Context

This DDR3 SDRAM implements an 8-bit prefetch architecture synchronized to differential CK/CK# 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 at 667 MHz.

The device supports programmable mode registers (MR0–MR3) for configuring burst length (BL8/BC4), read burst ordering (interleaved/nibble), additive latency (AL = 0, CL−1, CL−2), auto-precharge, and dynamic ODT (Rtt_WR). It also integrates ZQ calibration for output driver and ODT impedance tuning using an external 240 Ω reference resistor.

Key Specifications

Pinout & Package

VFBGA-78 package with 8 mm × 10.5 mm footprint, 1.0 mm profile, and ball pitch of 0.8 mm. Ball assignment follows JEDEC-standard DDR3 layout with dedicated VDD, VDDQ, VSS, VSSQ, address/command, data, strobe, and control balls.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar DDR3 SDRAM applications.

Compared with MT41K128M8RH-125:E, W631GG8NB-15 offers native 1.5 V operation and direct compatibility with legacy DDR3 controllers, while K4B1G0846F-BYMA provides identical electrical and mechanical specs with wider temperature coverage-making it suitable for harsher deployments without design revision.

Availability

W631GG8NB-15 is available at Aetrix Electronics and suitable for industrial automation, network infrastructure, medical imaging, and automated test equipment requiring stable component supply, long-lifecycle availability, and RoHS-compliant packaging.

Supply support for W631GG8NB-15 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 DDR SDRAM for industrial, automotive, and communications markets.

The W631GG8NB series belongs to Winbond's industrial-grade DDR3 SDRAM product line, designed specifically for thermally demanding embedded systems requiring JEDEC-compliant timing, robust power sequencing, and long-term supply stability.

FAQ

What is the maximum clock frequency supported by W631GG8NB-15?

W631GG8NB-15 supports a maximum clock frequency of 667 MHz, corresponding to DDR3-1333 (1333 MT/s) data transfer rate. This is confirmed by its speed grade suffix "-15", JEDEC-compliant 9-9-9 timing (tAA/tRCD/tRP = 13.5 ns minimum), and AC specification tables in the datasheet. The device maintains full functionality within its 0°C to 95°C case temperature range at this frequency.

Does W631GG8NB-15 support write leveling?

Yes, W631GG8NB-15 supports write leveling as a mandatory DDR3 feature. The device implements the standard DDR3 write leveling protocol using DQS gating and MPR readback to allow the memory controller to calibrate DQS-to-CK delay. This capability is explicitly documented in Section 8.9 of the datasheet and is essential for maintaining write setup/hold timing margins at 667 MHz on real-world PCB layouts.

What package type and dimensions does W631GG8NB-15 use?

W631GG8NB-15 uses a 78-ball Very Thin Fine-Pitch Ball Grid Array (VFBGA) package measuring 8 mm × 10.5 mm with 0.8 mm ball pitch and 1.0 mm maximum height. It is lead-free and RoHS compliant, matching JEDEC MO-270AC standard. This package is optimized for high-density routing and thermal performance in space-constrained industrial PCBs.

Can W631GG8NB-15 operate with VDDQ = 1.35 V for DDR3L compatibility?

No, W631GG8NB-15 is specified exclusively for VDD/VDDQ = 1.5 V ± 0.075 V and is not rated for DDR3L (1.35 V) operation. Its input thresholds, drive strength, and SSTL_15 interface are calibrated for 1.5 V signaling. Attempting 1.35 V operation may result in timing violations, reduced noise margin, or functional failure. For DDR3L compatibility, consider Winbond's W631GG8NB-L series or alternate vendors' DDR3L parts.

Is W631GG8NB-15 pin-compatible with other Winbond DDR3 parts like W631GG8NB-12?

Yes, all W631GG8NB speed grades-including W631GG8NB-12, W631GG8NB-11, and W631GG8NB-15-share identical 78-ball VFBGA package, pinout, and ball function mapping per JEDEC DDR3 standard. They differ only in AC timing specifications, temperature grading, and internal binning; thus, W631GG8NB-15 can be substituted for slower grades in existing designs without hardware modification, provided timing constraints are met.