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| Winbond Introduces Industry's First Quad-SPI Serial Flash Memory Winbond Electronics has announced the industry's first Serial Flash memory with Quad-SPI (Serial Peripheral Interface). The W25Q16 16-megabit SpiFlash Memory is the first in a family of high-performance memories ranging from 8 to 64 megabits, and features single, dual and quad I/Os in space- and cost-saving 8-pin packaging. The W25Q16's Quad-SPI architecture allows for greater than six times the performance of the current generation of Serial Flash memories and offers a true code-execution alternative to Parallel-NOR Flash. Prior to the introduction of the W25Q family, Serial Flash memories were used primarily for simple non-volatile storage of code that is downloaded to SDRAM at power-up (code-shadowing). With Quad-SPI performance, application-specific controllers can now execute code directly from Serial Flash, minimizing pin-count and SDRAM usage, and significantly reducing system costs. Quad–SPI can also dramatically improve boot time for traditional code-shadow applications. The W25Q16 is suited for a variety of consumer and industrial applications, including Blu-Ray Disc systems, DVD-HD and DVD-W drives, DVD players/recorders, WLAN and DSL equipment, PCs, digital-TV and set-top-boxes, printers, Bluetooth-based products, and FPGAs. Serial Flash offers many benefits over Parallel Flash memories including: reduced controller pin count, smaller and simpler PCBs, reduced switching noise, less power consumption, and lower system cost. As a result, Serial Flash unit volumes have grown by more than 400 percent since 2004 and represent 50 percent of the low-density (one- to 16-megabit) NOR Flash market. The W25Q16 SpiFlash memory builds on the success of Winbond's W25X family of SpiFlash memories (one- through 64-megabit densities). The 25Q16 maintains function- and pin-out compatibility with the 25X, while adding Dual-I/O and Quad-I/O SPI capability for higher performance. The 25Q16 supports clock rates up to 80MHz, enabling an equivalent clock frequency of 320MHz (40 megabytes per second continuous transfer rate) when using Quad-SPI operation. This is more than six times the transfer rate of standard Serial Flash memories that clock at 50MHz. Besides fast data transfer, the 25Q16 reduces "random access" overhead by more than 70 percent by slashing the number of clocks required per read instruction to 12, from 40. Efficient random access is essential for XIP operation. Assuming a typical instruction fetch of 32 bytes, the W25Q16 is capable of random access rates of greater than 32 megabytes per second. This outperforms 16-bit asynchronous Parallel Flash memories (70nS access, 100nS cycle time) by more than 50 percent. Besides its unprecedented performance, the W25Q16 also includes other important features, such as uniform 4K-byte erasable sectors for efficient memory allocation and storage of data. The 4K-byte sectors are commonly required in many Intel-based PC applications. The W25Q16 is also the first Serial Flash memory to offer erase-suspend/-resume capability, commonly found in parallel Flash memories and necessary for interrupt-driven systems that must temporally halt an erase operation to read from Flash memory. Security is also enhanced with lock-down and one-time-programmable write protection, and a 64-bit unique identification number that can be used as a seed for copy-protection schemes. write your comments about the article :: © 2007 Computing News :: home page |