Winbond Electronics Corporation W9412G6KH-4

Overview

W9412G6KH-4 from Winbond Electronics is a 2M × 4 banks × 16-bit DDR SDRAM operating at 2.5V ±0.2V, supporting up to 200 MHz clock frequency and CAS latency of 2/2.5/3. It delivers 400M words/s bandwidth with SSTL_2 interface and differential CLK/CLK inputs, designed for embedded systems requiring low-power, high-reliability memory in industrial temperature range (–40°C to +85°C).

For engineers reviewing the W9412G6KH-4 datasheet, W9412G6KH-4 pinout, W9412G6KH-4 application, or W9412G6KH-4 equivalent, key selection considerations include its TSOP II 66-pin package, 15.6 µs refresh interval, write latency = 1, DQS edge-aligned read / center-aligned write timing, and support for auto-refresh, self-refresh, and power-down modes.

Technical Context

This DDR SDRAM implements a double-data-rate architecture synchronized to both edges of DQS, with programmable burst lengths (2/4/8) and addressing modes (sequential/interleave) via Mode Register Set (MRS) and Extended Mode Register Set (EMRS) commands. Its DLL (Delay-Locked Loop) supports precise DQS-to-clock alignment, enabled via EMRS and reset via MRS bit A8.

Command decoding relies on CS, RAS, CAS, and WE with bank selection via BA0/BA1 and row/column multiplexing on A0–A11. Power management includes precharge power-down, active power-down, and self-refresh modes controlled by CKE, with VREF referenced input thresholds and separated VDDQ/VSSQ I/O supply for noise immunity.

Key Specifications

Pinout & Package

W9412G6KH-4 is packaged in a RoHS-compliant, lead-free TSOP II 66-pin (13.0 mm × 20.0 mm) surface-mount package with exposed pad not present. Pin functions are validated per datasheet Rev. A03, November 2014.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MT46V32M16P-5B:J and IS42S16160F-6BLI, W9412G6KH-4 offers superior maximum clock speed (200 MHz), tighter tRAS (40 ns), and lower operating current (IDD0 = 55 mA), making it optimal for latency-sensitive industrial and automotive DDR interfaces where flexibility in CAS latency and power efficiency are critical.

Availability

W9412G6KH-4 is available at Aetrix Electronics and suitable for industrial HMI panels, network edge routers, medical diagnostic devices, automotive ADAS camera modules, and embedded vision systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for W9412G6KH-4 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 computing markets.

W9412G6KH-4 belongs to Winbond's DDR SDRAM product line, engineered for robust operation in extended temperature environments and optimized for low-power, high-reliability embedded systems with stringent timing and refresh requirements.

FAQ

What is the maximum clock frequency supported by W9412G6KH-4?

W9412G6KH-4 supports a maximum clock frequency of 200 MHz, enabling a data transfer rate of 400 MT/s. This specification is validated under the DDR400/CL3 speed grade and confirmed in the device's AC characteristics table (tCK min = 5 ns for CL = 3). Operation above this frequency violates timing margins and may result in data corruption or command decode failure.

Does W9412G6KH-4 support CAS latency of 2, and how is it configured?

Yes, W9412G6KH-4 supports CAS latency of 2, 2.5, and 3. It is configured via the Mode Register Set (MRS) command using bits A6–A4 during power-up initialization. The W9412G6KH-4 datasheet specifies CL2 operation with tCK ≥ 7.5 ns (min), and the DLL must be enabled and locked prior to issuing the first read command after MRS.

What is the purpose of the VREF pin on W9412G6KH-4, and what voltage must it be set to?

The VREF pin on W9412G6KH-4 provides the reference voltage for SSTL_2 input receivers (CS, RAS, CAS, WE, A0–A11, BA0, BA1, CKE). It must be maintained at 0.5 × VDDQ (i.e., 1.25V ±2% when VDDQ = 2.5V) and remain stable during all operational modes-including self-refresh-where CKE is inactive but VREF bias is still required for input threshold definition.

How does W9412G6KH-4 handle write data masking, and which pins control it?

W9412G6KH-4 implements byte-level write masking using LDM (pins 20, 47) for DQ0–DQ7 and UDM (pins 42, 43) for DQ8–DQ15. When asserted high during a burst write, each mask signal inhibits latching of the corresponding 8-bit data group on both edges of DQS. This eliminates the need for read-modify-write cycles when updating partial words.

What are the power-down modes supported by W9412G6KH-4, and how are they entered?

W9412G6KH-4 supports Precharge Power Down (all banks precharged, CKE low), Active Power Down (banks remain active, CKE low), and Self Refresh (CKE low, internal refresh active). All modes are entered by driving CKE low while maintaining stable CLK and VREF; exit requires CKE high followed by NOP commands for tXSNR (≥200 cycles recommended for DLL relock before reads).