Memory devices provide execute-in-place capability

Silicon Storage Technology (SST) has announced a 1.8V, high-speed quad-bit serial flash memory.

Featuring an 80MHz operating frequency and a specialised instruction set, the 26WF Series Serial Quad I/O (SQI) range of 4-bit multiplexed I/O serial interface devices enables execute-in-place (XIP) capability, allowing programs to be stored and executed directly from the flash memory without the need for code shadowing on an SRAM.

The 26WF Series couples the performance typically associated with parallel flash memory, with the low pin count and space savings of serial flash memory, plus reduced power.

This combination of high performance and low power consumption is suitable for mobile handsets, Bluetooth headsets, GPS devices and other small form factor, portable electronics.

This device builds on SST's 3V SQI flash products, the 26VF Series.

Both 26 Series devices from SST feature a read memory indexing feature that enables the devices to achieve fast random access performance.

Read memory indexing allows the system to jump from one address to another within a 256-Byte page, within a 64-KByte block, or from one block to another using indirect addressing.

This results in a reduction in the number of clock cycles and accelerates data access.

With sustained burst data rates of up to 320Mbit/s, the 26WF Series devices provide serial flash performance exceeding that of typical parallel flash memory, according to SST.

To provide additional system speed and performance while reducing access time, the 26WF devices support 8-, 16-, 32- and 64-Byte burst-mode operation with wrap around.

This feature allows designers to execute code in burst snippets for RAM-less applications, or fill cache line buffers for applications where the system architecture uses pipelining to maximise bus bandwidth.

The 26WF Series SQI devices offer memory write performance enhancements to improve overall device performance, including flexible erase capability to erase small block sectors on the chip in as little as 25ms, or the entire flash memory chip in 50ms.

The devices also support write suspend and resume operation so a program can suspend a write operation to access another block of memory within the same clock cycle.

The 26WF Series SQI devices are built upon SST's native 1.8V Superflash memory cell, providing inherently higher performance when compared to alternative quad-bit devices that would require power-hungry charge pump circuitry for 1.8V operation, resulting in performance limitations.

The 26WF Series products offer a reliability of 100,000 cycles endurance (typical) and greater than 100 years data retention.

The active read current of the devices is 15mA (typical at 80MHz) and standby current is 10uA (typical).

To ensure code security, all 26WF Series devices support software write protection for individual blocks, the upper and lower 64-KBytes of memory are partitioned into smaller 8-KByte sectors that can both read and write lock.

In addition, the devices include a one-time programmable secure ID area, consisting of a 64-bit factory-programmed unique ID and a 192-bit user-programmable block.

All 26WF Series SQI devices are available in both commercial and industrial temperature ranges and are offered in an eight-contact WSON (6mm x 5mm) or eight-lead SOIC (200 mil) package.

In addition to the 1.8V 26WF Series, SST offers 3V SQI devices in 16Mbit and 32Mbit densities.

The first product in the 26WF Series SQI range is the 32Mbit SST26WF032.

Samples of the product are available now to select customers with volume production scheduled for Q1 2010.

Additional products in the series will be announced at a later date.

Back to top