Winbond Electronics Corporation W631GU6KB-11 TR

Overview

W631GU6KB-11 TR from Winbond is a 1G-bit DDR3L SDRAM organized as 8M × 8 banks × 16 bits, operating at 1.35V nominal supply with DDR3L-1866 (13-13-13) timing, supporting CAS Latency 13 and CWL 9, and delivering up to 1866 Mb/sec/pin data rates for memory subsystems in industrial and embedded computing platforms.

For engineers reviewing the W631GU6KB-11 TR datasheet, W631GU6KB-11 TR pinout, W631GU6KB-11 TR application, or W631GU6KB-11 TR equivalent, key selection considerations include its -11 speed grade compliance with JEDEC DDR3L-1866, 96-ball WBGA package, asynchronous RESET# support, ZQ calibration capability, and dual-voltage compatibility with legacy 1.5V DDR3 systems.

Technical Context

This DDR3L SDRAM implements an 8-bit prefetch architecture with eight internal banks enabling concurrent access, DLL-aligned DQ/DQS timing for precise source-synchronous I/O, and programmable mode registers (MR0–MR3) for configuring CAS Latency, CWL, ODT, PASR, ASR, and write leveling. It supports posted CAS with additive latency (AL = 0, CL−1, CL−2) and bi-directional differential DQS/DQS# strobes edge-aligned on reads and center-aligned on writes.

The device integrates on-die termination (ODT) with synchronous, dynamic, and asynchronous modes; ZQ calibration using an external 240Ω resistor; and power-down modes including precharged and active variants. Its asynchronous RESET# pin enables deterministic power-up initialization independent of clock stability, and MPR functionality provides system-level timing calibration via predefined read patterns.

Key Specifications

Pinout & Package

W631GU6KB-11 TR uses a 96-ball Wafer-Level Ball Grid Array (WBGA) package with 0.8 mm ball pitch, designed for high-density PCB layouts and thermal performance in space-constrained industrial applications. Pin functions follow JEDEC-standard DDR3L ballout mapping with dedicated VDDQ, VSSQ, VREFCA, VREFDQ, and ZQ balls.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar DDR3L SDRAM applications.

Compared with W631GU6KB-11 TR, both alternatives offer identical density and package but trade peak bandwidth for broader temperature qualification or relaxed timing margins-making them suitable for cost- or thermal-constrained designs where 1866 Mb/sec/pin is not required.

Availability

W631GU6KB-11 TR is available at Aetrix Electronics and suitable for industrial HMI controllers, network edge routers, medical imaging terminals, and ruggedized IoT gateways requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for W631GU6KB-11 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 solutions, including NOR/NAND Flash, SRAM, and DRAM products for industrial, automotive, and communications markets.

The W631GU6KB series belongs to Winbond's DDR3L SDRAM product line, engineered for low-voltage, high-reliability memory subsystems in thermally demanding embedded applications with strict power and timing constraints.

FAQ

What is the maximum operating frequency of the W631GU6KB-11 TR?

The W631GU6KB-11 TR supports a maximum clock frequency of 933 MHz, enabling DDR3L-1866 operation at 1866 Mb/sec/pin. This is validated under JEDEC conditions with CL=13, CWL=9, and tAA/tRCD/tRP = 13-13-13 ns. The device achieves this rate using DLL-aligned DQ/DQS timing and 8-bit prefetch architecture, and it remains stable across its specified 0°C to 95°C case temperature range.

Does the W631GU6KB-11 TR support backward compatibility with standard DDR3 systems?

Yes, the W631GU6KB-11 TR supports full backward compatibility with 1.5V DDR3 systems. Its VDD/VDDQ rails accept 1.5V ± 0.075V, and all command, address, and data timing parameters comply with JEDEC DDR3 standards when operated at that voltage. This allows drop-in replacement in existing DDR3 designs without layout changes, provided the controller supports DDR3L-specific features like ZQ calibration and ODT configuration.

How does the RESET# pin function on the W631GU6KB-11 TR?

The RESET# pin on the W631GU6KB-11 TR is an asynchronous, active-low input that initiates power-up initialization or functional reset independent of clock stability. When asserted, it forces the device into a known state and triggers the mandatory initialization sequence-including ZQ calibration and mode register programming-before normal operation resumes. This ensures deterministic startup behavior in systems with uncontrolled power sequencing.

What is the purpose of the ZQ ball on the W631GU6KB-11 TR?

The ZQ ball on the W631GU6KB-11 TR connects to an external 240Ω ±1% precision resistor to ground and enables on-die calibration of output driver strength and ODT impedance. During ZQ calibration commands, the DRAM measures this reference to adjust internal current sources, ensuring consistent signal integrity across voltage and temperature variations. This calibration must be performed at power-up and periodically during operation to maintain timing margins.

Can the W631GU6KB-11 TR operate in Partial Array Self-Refresh (PASR) mode?

Yes, the W631GU6KB-11 TR supports Partial Array Self-Refresh (PASR) via MR2 configuration (A1–A3 bits). PASR allows selective refresh of only active memory banks, reducing self-refresh current from 14 mA (full array) to proportionally lower values. This feature is especially valuable in battery-powered or thermally constrained industrial devices where minimizing idle power without sacrificing data retention is critical.