Winbond Electronics Corporation W631GU8KB-12

Overview

W631GU8KB-12 from Winbond Electronics is a 1 Gb (128 MB) DDR3L SDRAM organized as 16M × 8 banks × 8 bits, operating at 1.35 V nominal supply with DDR3L-1600 (11-11-11) timing, supporting CAS Latency 6–11 and programmable CWL 5–8. It delivers 1600 MT/s data rates per pin and is used in embedded computing, industrial HMIs, and network edge devices requiring low-voltage memory with JEDEC-compliant refresh and power-down modes.

For engineers reviewing the W631GU8KB-12 datasheet, W631GU8KB-12 pinout, W631GU8KB-12 application, or W631GU8KB-12 equivalent, key selection criteria include its -12 speed grade compliance with DDR3L-1600 (11-11-11), 78-ball WBGA package, support for ZQ calibration and dynamic ODT, and industrial temperature capability when ordered as -12I variant.

Technical Context

This DDR3L SDRAM implements an 8-bit prefetch architecture with eight internal banks enabling concurrent row activation and interleaved burst access. Its DLL-aligned DQS/DQ timing supports source-synchronous read/write operations, while posted CAS with additive latency (AL = 0, CL−1, CL−2) improves command bus efficiency.

The device integrates asynchronous RESET# for power-up initialization, programmable mode registers (MR0–MR3) for CAS latency, CWL, PASR, ASR, and ODT configuration, and supports write leveling, MPR-based timing calibration, and dual-voltage operation (1.35 V DDR3L or 1.5 V DDR3 backward compatibility).

Key Specifications

Pinout & Package

W631GU8KB-12 uses a 78-ball Wafer-Level Ball Grid Array (WBGA) package measuring 8 mm × 10.5 mm with 0.8 mm ball pitch. The package supports fine-pitch routing and compact layout in space-constrained embedded designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MT41K128M8RH-125:E and IS43TR16128B-125KBL, the W631GU8KB-12 offers broader voltage tolerance, integrated RESET#, and industrial temperature support in the -12I variant - making it preferable for ruggedized embedded systems where power sequencing control and thermal resilience are critical.

Availability

W631GU8KB-12 is available at Aetrix Electronics and suitable for industrial HMIs, network edge routers, and medical diagnostic terminals requiring stable component supply, long-term lifecycle assurance, and JEDEC-compliant DDR3L performance.

Supply support for W631GU8KB-12 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 W631GU8KB series belongs to Winbond's DDR3L SDRAM product line, designed specifically for cost-sensitive, thermally constrained embedded systems needing JEDEC-compliant low-voltage memory with robust initialization and power management features.

FAQ

What is the maximum operating frequency supported by W631GU8KB-12?

The W631GU8KB-12 is rated for DDR3L-1600 operation, supporting a maximum clock frequency of 800 MHz (1600 MT/s data rate). This is confirmed in the datasheet's Key Parameters table under fCKMAX = 800 MHz for the -12 speed grade. The device achieves this using CL=11, tRCD=11 ns, and tRP=11 ns timing, with actual achievable frequency dependent on system-level signal integrity and controller capabilities.

Does W631GU8KB-12 support both DDR3L and standard DDR3 voltage levels?

Yes, W631GU8KB-12 supports dual-voltage operation: it is fully compliant with DDR3L specifications at 1.35 V (VDD/VDDQ = 1.283 V to 1.45 V) and backward compatible with standard DDR3 at 1.5 V (±0.075 V). This allows seamless integration into legacy 1.5 V systems without hardware modification, though full DDR3L power savings are realized only at 1.35 V operation.

How does the RESET# pin function in W631GU8KB-12 initialization?

The RESET# pin in W631GU8KB-12 provides asynchronous reset control independent of power sequencing. When asserted low, it forces the device into a known state and initiates the power-up initialization sequence - including DLL locking and mode register loading - before any commands are accepted. This eliminates reliance on precise VDD ramp timing, simplifying system-level power management for the W631GU8KB-12.

What termination options does W631GU8KB-12 provide for signal integrity?

W631GU8KB-12 supports multiple termination schemes: programmable on-die termination (ODT) with RTT_NOM (60/120/240 Ω) and RTT_WR (60/120 Ω) values, dynamic ODT activation during writes, and ZQ calibration using an external 240 Ω resistor. These features collectively minimize reflections on DQ/DQS/DM lines, enabling reliable 1600 MT/s operation in dense PCB layouts without external resistors.

Can W631GU8KB-12 operate in extended temperature ranges?

The W631GU8KB-12 variant is specified for 0°C ≤ TCASE ≤ 95°C, but full JEDEC AC/DC specifications apply only from 0°C to 85°C. For operation up to 95°C, the device requires either Manual Self-Refresh with Extended Temperature Range mode (MR2[7:6] = 01b) or Auto Self-Refresh (ASR) enabled (MR2[6] = 1b), doubling refresh rate to 3.9 µS intervals. The industrial-grade W631GU8KB12I variant guarantees full specification compliance across -40°C to 95°C.