Winbond Electronics Corporation W9864G2JH-6

Overview

W9864G2JH-6 from Winbond is a 512K × 4 banks × 32-bit synchronous DRAM (SDRAM) operating at 166 MHz with CAS Latency 3, 3.3V ±0.3V supply, and TSOP II-86 package. It delivers 166M words/sec bandwidth and supports auto-precharge, burst lengths of 1/2/4/8/full-page, and interleaved bank access for high-throughput memory subsystems in embedded controllers and industrial HMIs.

For engineers reviewing the W9864G2JH-6 datasheet, W9864G2JH-6 pinout, W9864G2JH-6 application, or W9864G2JH-6 equivalent, key selection criteria include its 166 MHz/CL3 timing grade, TSOP II-86 mechanical compatibility, DQM-controlled byte masking, LVTTL interface compliance, and self-refresh current of 2 mA - all critical for legacy SDRAM-based designs requiring drop-in replacement and long-term availability.

Technical Context

This SDRAM implements four independent 512K-word banks with shared address/command bus and separate DQ/DQM I/O paths. Its operation relies on precise command sequencing-bank activation (tRCD ≥ 20 ns), read/write with programmable burst mode (sequential or interleave), and mandatory precharge before bank reactivation (tRP ≥ 20 ns).

Internal timing is fully synchronous to CLK rising edge; CKE controls clock enable/disable for power-down and self-refresh entry/exit. Mode Register configuration sets burst length, CAS latency, and burst type, while A10 controls auto-precharge activation during read/write commands - enabling efficient page-mode access across banks without external refresh management.

Key Specifications

Pinout & Package

W9864G2JH-6 is housed in a RoHS-compliant, lead-free TSOP II-86 package with 86 pins arranged in two rows. The package supports standard surface-mount assembly and thermal performance suitable for industrial ambient temperatures (0°C to 70°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with W9864G2JH-5, the W9864G2JH-6 trades 34 MHz bandwidth for relaxed timing margins and broader design reuse; compared with W9864G2JH-6I, it offers identical functionality at lower cost for commercial-temperature applications - making it optimal for cost-sensitive, volume-manufactured embedded systems with controlled thermal environments.

Availability

W9864G2JH-6 is available at Aetrix Electronics and suitable for industrial HMIs, legacy FPGA-based data acquisition systems, and medical device boot memory requiring stable component supply, long-lifecycle support, and TSOP II-86 footprint compatibility.

Supply support for W9864G2JH-6 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 SPI NOR Flash, PSRAM, and SDR/DDR SDRAM for industrial, automotive, and consumer applications.

The W9864G2JH series belongs to Winbond's legacy SDRAM product line designed for cost-sensitive, non-graphics embedded systems requiring reliable, pin-compatible memory with long-term manufacturing continuity and industrial temperature support.

FAQ

What is the maximum operating frequency and CAS latency of the W9864G2JH-6?

The W9864G2JH-6 is rated for a maximum clock frequency of 166 MHz with a fixed CAS latency of 3 (CL3). This means the first valid data appears on DQ three clock cycles after the column address is latched. The timing is guaranteed across the commercial temperature range (0°C to 70°C), and all AC parameters-including tRCD, tRP, and tRC-are specified accordingly in the datasheet revision A03.

Does the W9864G2JH-6 support both sequential and interleaved burst modes?

Yes, the W9864G2JH-6 supports both sequential and interleaved burst addressing modes. The mode is selected via the Mode Register Set (MRS) command, where bit M3 configures burst type. Sequential mode increments column address linearly (e.g., n, n+1, n+2); interleaved mode toggles LSBs per burst cycle. Both modes are supported for burst lengths of 1, 2, 4, 8, and full-page, and are functionally identical in the W9864G2JH-6 datasheet.

What is the purpose of the DQM0–DQM3 pins on the W9864G2JH-6?

The DQM0–DQM3 pins on the W9864G2JH-6 provide per-byte masking control for the 32-bit DQ bus. During write operations, asserting a DQM pin high blocks data transfer to the corresponding 8-bit byte lane with zero latency. During read operations, asserting DQM high places the associated DQ byte in high-impedance state after CL+2 clocks - preventing bus contention when partial reads are needed. This enables efficient 8-/16-bit data transfers without external logic.

Can the W9864G2JH-6 enter self-refresh mode, and what is its typical current draw?

Yes, the W9864G2JH-6 supports self-refresh mode, entered via the Self Refresh Command (CS=RAS=CAS=WE=low, CKE=low at CLK rise). In this mode, the device internally manages row refresh without external clock or command input. The datasheet specifies a typical self-refresh current of 2 mA at VDD = 3.3V and TA = 25°C - enabling low-power data retention during system sleep states while maintaining full memory integrity.

Is the W9864G2JH-6 pin-compatible with other speed grades in the same family?

Yes, the W9864G2JH-6 is fully pin-compatible with W9864G2JH-5, W9864G2JH-6I, and W9864G2JH-7. All variants share identical TSOP II-86 pinout, signal definitions, and DC/AC electrical characteristics except for speed-grade-specific timing parameters (e.g., tAC, tRC, tRCD). No PCB redesign is required when substituting between these grades - only timing configuration in the memory controller must be updated to match the selected speed bin.