Winbond Electronics Corporation W988D6FBGX7E

Overview

W988D6FBGX7E from Winbond is a 256Mb (4,194,304 × 16) low-power synchronous DRAM IC designed for mobile memory subsystems. It operates at 133MHz with 1.8V VDD/VDDQ supply, CAS latency of 2 or 3, and supports Partial Array Self Refresh (PASR) and Automatic Temperature Compensated Self Refresh (ATCSR) for battery-powered handheld devices.

For engineers reviewing the W988D6FBGX7E datasheet, W988D6FBGX7E pinout, W988D6FBGX7E application, or W988D6FBGX7E equivalent, this device requires attention to its 54-ball VFBGA x16 ball map, LVCMOS interface timing, deep power-down entry/exit sequence, and bank activation/precharge command compatibility in mobile SoC memory controllers.

Technical Context

This LPSDR implements a fully synchronous architecture with four independent banks, row/column address multiplexing via A0–A12 and BA0/BA1, and command decoding synchronized to CLK rising edges. It supports burst lengths of 1, 2, 4, 8, and full page, with auto-precharge triggered by A10 high during read/write commands.

Power management includes three distinct low-power states: Power Down Mode (CKE low), Self Refresh (CKE low + all banks idle), and Deep Power Down Mode (CKE low + /CS low). The device uses separate VDDQ/VSSQ rails for I/O buffers to reduce switching noise and improve signal integrity in dense mobile PCB layouts.

Key Specifications

Pinout & Package

W988D6FBGX7E is housed in a 54-ball Very Thin Fine-Pitch Ball Grid Array (VFBGA) package measuring 8mm × 10.5mm × 0.6mm, optimized for space-constrained mobile PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with W988D6FBGX7E, W988D6FBGX6E offers higher speed and broader temperature tolerance at identical pinout, while MT48LC16M16A2P-75 provides basic SDR functionality in a larger, less power-efficient package without advanced low-power modes.

Availability

W988D6FBGX7E is available at Aetrix Electronics and suitable for smartphone baseband subsystems, digital still camera image pipelines, portable gaming console memory subsystems, and industrial handheld terminal designs requiring stable component supply and long-lifecycle support.

Supply support for W988D6FBGX7E 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 memory solutions, flash storage, and security ICs, with over 30 years of DRAM design heritage and ISO/TS 16949-certified manufacturing.

The W988D6FB series belongs to Winbond's Low Power SDRAM product line, engineered specifically for battery-operated portable electronics demanding high density, sub-2V operation, and multi-tier power-state management.

FAQ

What is the maximum operating frequency of the W988D6FBGX7E?

The W988D6FBGX7E is rated for a maximum clock frequency of 133MHz, corresponding to the "-75" speed grade in Winbond's ordering nomenclature. This frequency defines the upper limit for reliable command execution, data transfer, and timing parameter compliance per the device's AC specifications. Operation above 133MHz is not guaranteed and may violate tAC, tRCD, or tRP timing margins. The W988D6FBGX7E must be configured with appropriate CAS latency (CL=2 or CL=3) and burst length settings to maintain stability at this rate.

Does the W988D6FBGX7E support automatic temperature-compensated self-refresh?

Yes, the W988D6FBGX7E implements Automatic Temperature Compensated Self Refresh (ATCSR), a hardware feature that dynamically reduces self-refresh current as ambient temperature decreases. This function operates without host controller intervention and is enabled by default after power-up. ATCSR lowers typical self-refresh current from ~35μA at 85°C to ≤15μA at 25°C, directly extending battery life in portable applications where thermal conditions vary significantly during use.

What package type and ball count does the W988D6FBGX7E use?

The W988D6FBGX7E uses a 54-ball Very Thin Fine-Pitch Ball Grid Array (VFBGA) package with 0.5mm pitch, measuring 8mm × 10.5mm × 0.6mm. This package supports the x16 data bus configuration and is mechanically and electrically compatible with other members of the W988D6FB family, including W988D6FBGX6E and W988D6FBGX6I. Its compact footprint and low profile make it suitable for thin mobile devices where PCB area and Z-height are constrained.

Can the W988D6FBGX7E operate in Deep Power Down Mode?

Yes, the W988D6FBGX7E supports Deep Power Down Mode (DPD), entered by asserting /CS low while CKE is low. In DPD, core logic and I/O circuits are powered down, reducing standby current to ≤1μA. Exit requires a specific sequence: CKE high for ≥100ns, followed by /CS high and a NOP command. This mode is ideal for applications requiring months-long battery retention, such as IoT sensors or emergency backup systems, and is distinct from standard Power Down or Self Refresh modes.

What is the role of the A10 pin on the W988D6FBGX7E?

On the W988D6FBGX7E, the A10 pin serves as the Auto Precharge Select (AP) signal. When A10 is driven high during a READ or WRITE command, the device automatically issues a precharge command to the accessed bank at the end of the burst. When A10 is low, no auto-precharge occurs, allowing multiple accesses to the same open row. This dual-function pin eliminates the need for explicit PRE commands in many sequential access patterns, simplifying controller logic and improving effective bandwidth in burst-oriented workloads.