Winbond Electronics Corporation W988D2FBJX7E

Overview

W988D2FBJX7E from Winbond is a 256Mb low-power synchronous DRAM (LPSDR) with x32 I/O width, 133MHz max clock frequency, 1.8V VDD/VDDQ supply, and 90-ball VFBGA package. It implements Partial Array Self Refresh (PASR), Automatic Temperature Compensated Self Refresh (ATCSR), and Deep Power Down Mode for battery-constrained mobile applications including 3G/4G handsets and digital still cameras.

For engineers reviewing the W988D2FBJX7E datasheet, W988D2FBJX7E pinout, W988D2FBJX7E application, or W988D2FBJX7E equivalent, this page delivers verified electrical specs, ball assignment mapping, low-power timing behavior, and validated alternative parts for portable memory subsystem design.

Technical Context

This LPSDR operates in fully synchronous mode with data synchronized to positive CLK edges, supports burst lengths of 1, 2, 4, 8, and full-page, and uses BA0/BA1 to select among four internal banks. Addressing uses multiplexed row/column inputs with A10 controlling Auto Precharge.

Command decoding relies on CS, RAS, CAS, and WE sampled at CLK rising edges; CKE enables/disables clock domain entry into Power Down, Clock Suspend, or Self Refresh modes. DQM0–DQM3 provide per-quad write masking and output disable control with zero-latency blocking in write cycles.

Key Specifications

Pinout & Package

W988D2FBJX7E uses a 90-ball Very Thin Fine-Pitch Ball Grid Array (VFBGA) package with 0.5mm ball pitch. Signal balls are arranged in 10×9 grid (A1–J10), with dedicated power/ground distribution across VDD, VDDQ, VSS, and VSSQ banks.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-power mobile SDRAM applications.

Compared with W988D2FBJX7E, W988D2FBJX6E offers higher speed headroom within identical package and thermal envelope, while IS42S32800J-7BLI trades Winbond-specific low-power features for wider temperature qualification and alternate vendor supply chain diversification.

Availability

W988D2FBJX7E is available at Aetrix Electronics and suitable for smartphone baseband memory, digital still camera buffers, and portable gaming console memory requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production lots.

Supply support for W988D2FBJX7E 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, DDR/SDR/LPSDR, and TrustME secure memory products.

The W988D2FB series belongs to Winbond's Low Power SDRAM product line, designed specifically for battery-operated handheld devices demanding high memory density, JEDEC-compliant timing, and multi-layer power management including PASR, ATCSR, and Deep Power Down.

FAQ

What is the maximum operating frequency of the W988D2FBJX7E?

The W988D2FBJX7E is rated for a maximum clock frequency of 133MHz, corresponding to a -75 speed grade. This frequency defines the upper limit for reliable command execution, burst transfer timing, and CAS latency (CL=3) compliance per JEDEC LPSDR specifications. At this speed, the device delivers up to 426MB/s peak bandwidth with x32 interface width. The W988D2FBJX7E datasheet specifies AC timing parameters-including tAC, tRC, and tRCD-exclusively for 133MHz operation.

Does the W988D2FBJX7E support automatic temperature-compensated self-refresh?

Yes, the W988D2FBJX7E implements Automatic Temperature Compensated Self Refresh (ATCSR), a hardware-controlled feature that dynamically adjusts self-refresh current based on die temperature. This ensures data retention across the full −25°C to +85°C operating range while minimizing average power consumption. ATCSR is enabled by default after power-up and requires no software configuration; it operates independently of external thermal sensors or host intervention. The W988D2FBJX7E datasheet details ATCSR current vs. temperature curves in Section 9.5.

What package type and ball count does the W988D2FBJX7E use?

The W988D2FBJX7E uses a 90-ball Very Thin Fine-Pitch Ball Grid Array (VFBGA) package measuring 7.0mm × 9.0mm × 0.65mm with 0.5mm ball pitch. This package supports x32 data width and is mechanically and thermally optimized for space-constrained mobile PCBs. Ball assignments follow JEDEC MO-244AA standard layout, with dedicated VDD/VDDQ/VSS/VSSQ banks and DQM0–DQM3 distributed across quadrants for balanced signal integrity. The W988D2FBJX7E pinout is documented in Section 4.2 of its official datasheet.

How does Partial Array Self Refresh (PASR) function in the W988D2FBJX7E?

Partial Array Self Refresh (PASR) in the W988D2FBJX7E allows selective refresh of only active memory subarrays-such as ¼, ½, or ¾ of total banks-reducing self-refresh current by up to 50% compared to full-array refresh. PASR is configured via Extended Mode Register Set (EMRS) commands using A12/A11 bits. It is particularly valuable in applications like camera preview or UI rendering where only a fraction of memory capacity is actively used. The W988D2FBJX7E implements PASR without requiring host firmware changes beyond standard EMRS writes.

What are the key low-power modes supported by the W988D2FBJX7E?

The W988D2FBJX7E supports three distinct low-power states: Power Down Mode (CKE-driven, ~10µA), Clock Suspend Mode (CKE-driven, lower than Power Down), and Deep Power Down Mode (DPD, ≤1µA). DPD provides the lowest quiescent current but requires longer exit latency (~100µs) and full initialization sequence upon wake. All modes retain data without external refresh. The W988D2FBJX7E enters these states via specific command sequences defined in Sections 7.1.19–7.1.21 and Table 1 of its datasheet, with CKE as the primary control signal.