Winbond Electronics Corporation W971GG6SB-25

Overview

W971GG6SB-25 from Winbond Electronics is a 1G-bit DDR2 SDRAM organized as 8M × 8 banks × 16 bits, compliant with DDR2-800 (5-5-5 or 6-6-6) timing, operating at 1.8 V ± 0.1 V supply, and supporting CAS latencies of 3–7 for use in embedded computing, industrial control, and legacy communication baseband systems.

For engineers reviewing the W971GG6SB-25 datasheet, W971GG6SB-25 pinout, W971GG6SB-25 application, or W971GG6SB-25 equivalent, key selection considerations include tRCD = 12.5 ns, tRP = 12.5 ns, ODT programmability, differential clock interface (CLK/CLK), and WBGA-84 package compatibility with JEDEC-compliant DDR2 memory controllers.

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), additive latency (RL = AL + CL), and write latency WL = RL − 1.

Functional operation includes on-die termination (ODT) controlled via dedicated ODT pin, off-chip driver (OCD) impedance calibration, auto-precharge, self-refresh, and power-down modes (precharged and active). All commands are registered on the rising edge of CLK, with address/control latching at CLK/CLK crossing points.

Key Specifications

Pinout & Package

W971GG6SB-25 is packaged in an 8 mm × 12.5 mm, 84-ball fine-pitch WBGA (Wafer-Level Ball Grid Array) with RoHS-compliant lead-free finish and isolated VSSQ/VDDQ planes for signal integrity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MT47H128M8SH-25E and IS42S16160F-25BLI, W971GG6SB-25 offers identical density and timing but prioritizes cost-effective WBGA packaging and optimized IDD performance for commercial-temperature embedded systems with strict layout constraints.

Availability

W971GG6SB-25 is available at Aetrix Electronics and suitable for industrial HMI controllers, legacy telecom baseband modules, and medical diagnostic imaging systems requiring stable component supply, long-term lifecycle assurance, and JEDEC-compliant DDR2 interoperability.

Supply support for W971GG6SB-25 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 products for industrial and communications markets.

W971GG6SB-25 belongs to Winbond's DDR2 SDRAM product line, designed specifically for cost-sensitive, space-constrained embedded systems requiring JEDEC-standard memory with industrial-grade reliability and simplified power delivery.

FAQ

What is the maximum operating frequency supported by W971GG6SB-25?

W971GG6SB-25 supports DDR2-800 operation, meaning it achieves a maximum data transfer rate of 800 Mb/sec per pin. This corresponds to a 400 MHz clock frequency with two data transfers per cycle. The device meets JEDEC timing specifications for tCK(min) = 2.5 ns at CL = 5 and tRCD/tRP = 12.5 ns, validated across 0°C to 85°C case temperature.

Does W971GG6SB-25 support differential DQS operation?

Yes, W971GG6SB-25 supports differential data strobes via UDQS/UDQS and LDQS/LDQS pairs. This mode is enabled through Extended Mode Register Set (EMRS) command to EMR(1) with A10 = HIGH. When active, the strobes operate edge-aligned with read data and center-aligned with write data, improving timing margin over single-ended implementations.

How is On-Die Termination (ODT) controlled on W971GG6SB-25?

ODT on W971GG6SB-25 is controlled by the dedicated ODT pin (Ball K9), which must be driven HIGH to enable internal termination resistors (75 Ω or 150 Ω depending on EMR(1) configuration). ODT is only active during read operations and is disabled automatically during writes or when ODT is LOW. No external resistor network is required when ODT is enabled.

What is the purpose of the VREF pin on W971GG6SB-25?

The VREF pin (Ball J2) provides the reference voltage for all SSTL_18 input receivers (address, command, and control signals). It must be maintained at VDDQ/2 ± 300 mV and is typically generated by a dedicated resistor divider or low-noise reference IC. Stable VREF ensures consistent input threshold levels and prevents setup/hold violations under voltage or temperature variation.

Can W971GG6SB-25 operate in self-refresh mode at 85°C?

Yes, W971GG6SB-25 supports self-refresh mode across its full specified operating temperature range of 0°C ≤ TCASE ≤ 85°C, with maximum IDD6 current of 8 mA. At 85°C, the device maintains data retention using standard tREFI = 7.8 μs refresh intervals without requiring accelerated refresh rates or special register settings.