Winbond Electronics Corporation W958D8NBYA4I TR

Overview

W958D8NBYA4I TR from Winbond Electronics is a 256Mb HyperRAM device implementing the HyperBus DDR interface for high-speed, low-pin-count memory expansion in resource-constrained embedded systems. It operates at 1.8V, supports up to 250MHz clock frequency (500 MB/s peak throughput), and uses an 8-bit bidirectional data bus with RWDS strobe/mask functionality. It is deployed as external RAM in microcontroller-based HMI displays requiring fast frame buffer access.

For engineers reviewing the W958D8NBYA4I TR datasheet, W958D8NBYA4I TR pinout, W958D8NBYA4I TR application, or W958D8NBYA4I TR equivalent, key selection criteria include HyperBus compatibility, 24-ball TFBGA package footprint, configurable burst modes (wrapped/linear/hybrid), deep power-down support, and -40°C to +85°C industrial temperature operation.

Technical Context

The W958D8NBYA4I TR implements a DDR HyperBus interface with differential (CK/CK#) or single-ended (CK) clocking, using DQ[7:0] for command/address/data multiplexing and RWDS for latency indication, read strobe, and write masking. Its internal architecture includes row/column decoders, data latches, and configurable refresh logic supporting full/partial array refresh.

It supports two distinct burst types per transaction-wrapped (for cache-line fills) and linear (for sequential graphics transfers)-with hybrid burst enabling one wrapped segment followed by linear continuation. Latency is dynamically determined via RWDS during Command/Address phase, and initial latency is programmable via Configuration Register 0.

Key Specifications

Pinout & Package

W958D8NBYA4I TR is housed in a 24-ball TFBGA package (5×5 mm, 0.8 mm pitch, SDP footprint), optimized for space-constrained PCB layouts in portable and automotive displays.

Key Features

Applications

Equivalent & Alternatives

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

Compared with W958D8NBYA5I, the W958D8NBYA4I TR delivers 25% higher bandwidth for graphics-intensive applications; versus IS66WV51216EBLL-15BLI, it reduces interface complexity and power but requires HyperBus-aware firmware and layout discipline for DDR timing closure.

Availability

W958D8NBYA4I TR is available at Aetrix Electronics and suitable for industrial HMI displays, automotive digital clusters, smart home control panels, and medical patient monitors requiring stable component supply and long-term manufacturability.

Supply support for W958D8NBYA4I TR 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, SPI NAND, and HyperRAM products for embedded systems.

The W958D8NBYA4I TR belongs to Winbond's HyperRAM family, designed specifically to replace parallel PSRAM and low-density DDR SDRAM in MCU-based applications where pin count, power, and simplicity are critical.

FAQ

What is the maximum data throughput achievable with the W958D8NBYA4I TR?

The W958D8NBYA4I TR achieves up to 500 MB/s peak read throughput using its 250MHz DDR HyperBus interface (1.8V, 8-bit bus). This assumes linear burst mode with interleaved row access and optimal host controller timing - verified in Winbond's characterization under JEDEC JESD22-A108 conditions at 85°C case temperature. Real-world sustained throughput depends on burst length, latency configuration, and host bus arbitration.

Does the W958D8NBYA4I TR support both differential and single-ended clocking?

Yes, the W958D8NBYA4I TR supports both differential (CK/CK#) and single-ended (CK only) clocking modes. In differential mode, CK# must be driven complementary to CK; in single-ended mode, CK# is unused and may be left unconnected. The device automatically detects clock mode based on CK# voltage level during power-up initialization, as defined in Configuration Register 1, Bit [15].

How does the RWDS signal function during read versus write transactions in the W958D8NBYA4I TR?

In read transactions, RWDS acts first as a latency indicator during Command/Address (CA) phase (High = additional tACC), then as an edge-aligned read data strobe. In write transactions, RWDS serves as a byte-level mask (High = masked, Low = written) during data transfer - enabling unaligned writes and merging of partial-word updates without software overhead. This dual-role behavior is intrinsic to the HyperBus protocol implemented in the W958D8NBYA4I TR.

What package type and footprint does the W958D8NBYA4I TR use?

The W958D8NBYA4I TR uses a 24-ball TFBGA package (5×5 mm, 0.8 mm ball pitch) with SDP (Single Die Package) construction. Its pinout matches JEDEC MO-276AA standard, and the footprint is documented in Winbond's Package Specification document (Rev. A01-002, Section 13). This compact package enables high-density routing in space-constrained applications like portable medical devices and automotive clusters.

Can the W958D8NBYA4I TR operate in deep power-down mode while retaining data?

No, the W958D8NBYA4I TR does not retain memory contents in Deep Power Down mode - it enters a state where the memory array is powered off and all data is lost. Data retention requires at least Interface Standby or Active Clock Stop mode. Deep Power Down is intended for extended idle periods where data persistence is handled externally (e.g., by saving state to flash before entry), and the W958D8NBYA4I TR resumes from reset upon exit.