Winbond Electronics Corporation W949D2DBJX5I TR

Overview

W949D2DBJX5I from Winbond is a 512Mb mobile LPDDR SDRAM with x32 data bus, 200MHz clock rate, 1.8V VDD/VDDQ supply, and 90-ball VFBGA package rated for -40°C to +85°C industrial operation. It delivers burst-oriented random-access memory for mobile SoC subsystems requiring low-power, high-bandwidth data buffering in smartphones, tablets, and portable embedded systems.

For engineers reviewing the W949D2DBJX5I datasheet, W949D2DBJX5I pinout, W949D2DBJX5I application, or W949D2DBJX5I equivalent, key selection criteria include CAS latency (CL=2/3), partial array self-refresh (PASR), automatic temperature-compensated self-refresh (ATCSR), deep power-down mode, and differential clock interface compatibility with LPDDR controllers.

Technical Context

This LPDDR SDRAM implements four independent internal banks supporting bank interleaving to hide precharge latency. It uses differential CK/CK inputs and bidirectional DQS strobes (DQS0–DQS3) aligned with x32 data lanes (DQ0–DQ31), enabling double-data-rate transfers synchronized to both clock edges.

Initialization requires strict sequencing: power ramp with CKE high, ≥200μs stable clocks, PRECHARGE ALL, two AUTO REFRESH commands, then Mode Register and Extended Mode Register programming. Supported low-power states include Power Down, Deep Power Down, Clock Stop, and Self Refresh with ATCSR and PASR for dynamic power optimization.

Key Specifications

Pinout & Package

W949D2DBJX5I uses a 90-ball Very Fine Pitch Ball Grid Array (VFBGA) package measuring 10.5mm × 12.5mm × 0.6mm (JEDEC MO-247AC), optimized for space-constrained mobile PCBs with fine-pitch routing.

Key Features

Applications

Equivalent & Alternatives

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

Compared with W949D2DBJX5I, MT52L256M32D1PF-107 WT:A offers automotive qualification but demands 1.2V I/O and tighter timing margins, while K4E6E304EC-EGCF provides identical speed and density without industrial temperature range or adaptive refresh - making W949D2DBJX5I the optimal choice for thermally demanding, battery-constrained industrial mobile designs.

Availability

W949D2DBJX5I is available at Aetrix Electronics and suitable for smartphone application processor memory, tablet GPU frame buffers, industrial handheld terminal RAM, automotive infotainment systems, and portable medical device data logging requiring stable component supply across long production lifecycles.

Supply support for W949D2DBJX5I 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, LPDDR SDRAM, and TrustME® secure flash.

The W949D2DBJX5I belongs to Winbond's mobile LPDDR SDRAM product line, engineered specifically for ultra-low-power, high-density memory in space- and energy-constrained portable electronics.

FAQ

What is the exact memory organization of the W949D2DBJX5I?

The W949D2DBJX5I is a 512Mb LPDDR SDRAM organized as 4 banks × 8,192 rows × 256 columns × 32 bits. This yields 64MB total capacity with x32 data width. Row address A0–A12 and column address A0–A8 are used in x32 configuration, with BA0/BA1 selecting among the four internal banks. The W949D2DBJX5I does not support x16 operation - it is exclusively a 90-ball x32 device.

Does the W949D2DBJX5I support LPDDR3 protocol or an earlier generation?

The W949D2DBJX5I implements the JEDEC LPDDR2 standard, not LPDDR3. Its datasheet specifies CAS latencies of CL=2 and CL=3, 200MHz/166MHz clock options, and features such as Partial Array Self Refresh (PASR) and Automatic Temperature Compensated Self Refresh (ATCSR) consistent with LPDDR2. It is not electrically or protocol-compatible with LPDDR3 controllers due to differences in command encoding, timing parameters, and voltage thresholds.

What are the critical timing requirements for initializing the W949D2DBJX5I?

Initialization of the W949D2DBJX5I requires strict adherence to sequence and timing: (1) VDD/VDDQ ramp with CKE held HIGH; (2) ≥200μs of stable clocks before first command; (3) PRECHARGE ALL; (4) tRP delay; (5) two AUTO REFRESH commands each followed by ≥tRFC delay; (6) Mode Register Set; (7) ≥tMRD delay; (8) Extended Mode Register Set; (9) ≥tMRD delay. Skipping or shortening any step risks undefined behavior or initialization failure.

How does the Deep Power Down (DPD) mode function in the W949D2DBJX5I?

In Deep Power Down mode, the W949D2DBJX5I shuts down all internal circuitry except retention logic, drawing <10μA typical current while preserving memory contents. Entry requires CKE LOW, CS LOW, and specific command sequences; exit is initiated by driving CKE HIGH and waiting ≥100μs before issuing valid commands. DPD is ideal for long idle periods in battery-powered devices where zero-refresh standby is mandatory.

Can the W949D2DBJX5I be used with a 1.2V I/O interface?

No - the W949D2DBJX5I requires VDDQ = 1.8V ±5% and is not compatible with 1.2V interfaces. Its input thresholds, output drive strength, and LVCMOS signaling are specified only for 1.8V operation. Interfacing with a 1.2V controller would require level-shifting circuitry and invalidate timing margins, potentially causing data corruption or initialization failure. Always use a 1.8V-compatible memory controller.