Sequential read function in high-speed QspiNAND Flash

Automotive and IoT device manufacturers are increasingly adopting high-performance Single-Level Cell (SLC) NAND Flash as a low-cost alternative at densities of 512Mbits and higher to the NOR Flash traditionally used for code storage.

Previous Winbond innovations in high-performance NAND Flash include the Quad SPI-NAND interface, which shares the same 6-pin signals and QSPI command set as Quad SPI-NOR, and the Continuous Read function, which achieves up to a 52MB/s continuous data transfer rate at a 104MHz clock frequency.

Now Winbond has created another innovation in high-performance NAND Flash with the introduction of the Sequential Read function in its latest high-performance W25NxxxJW QspiNAND Flash devices. In Sequential Read mode, the QspiNAND Flash products achieve the same 52MB/s maximum data rate at 104MHz as in Continuous Read mode, but with new flexibility to configure the chip’s operation. The most important new options are:

• Freedom to apply the user’s own ECC engine. In Continuous Read mode, a Winbond W25N device only supports its own on-chip 1-bit ECC engine. In Sequential Read mode, users can implement 4-bit, 8-bit or any-bit error correction when enabled by an external ECC engine.
• Access to the entire memory array – both the Main Area and the Spare Area - with a single Read command. This is ideal for code shadowing applications in which low latency and fast boot time are particularly important.
• Greater flexibility to configure the data arrangement to suit the user’s application.

“By providing for high-speed operation with its Continuous Read function, Winbond had already made QspiNAND Flash a viable option for use in code storage applications, including for code shadowing and execute-in-place operations,” said Syed S. Hussain, Director Segment Marketing, Winbond Electronics America Flash Business Group. “Now the addition of Sequential Read means that users can benefit from the same high Read speed of up to 52MB/s while implementing their chosen ECC engine and data access arrangements.”

The new 1.8V QspiNAND Flash products are available in densities of 512Mb, 1Gb and 2Gb. The 3.0V versions are available in densities of 2Gb and 4Gb. All are manufactured in the company’s 12-inch wafer fabrication facility in Taichung, Taiwan. Winbond is expanding capacity to meet new demand expected in both the automotive and IoT market segments.

The new W25N QspiNAND Flash devices are offered in compact 8-pin packages – a space-saving format which was not possible for SLC-NAND Flash memory products before Winbond’s development of an effective QspiNAND Flash interface. Clock speeds of 104MHz allow the equivalent of 416MHz (104MHz x 4) speed for Quad I/O performance when using the Fast Read Dual/Quad I/O instructions. To provide better NAND Flash memory manageability, the devices perform on-chip bad block management.

Key features

Wide temperature range

• -40 to +85°C operating range in Industrial GRADE
• -40°C to +105°C operating range in Industrial plus and Automotive GRADE

Unique memory architecture

• Page Read Time with ECC Enabled: 50μs
• Page Program Time: 250μs (typ.)
• Block Erase Time: 2ms (typ.)
• Fast Program/Erase performance
• Supports OTP Memory Area

High-performance QspiNAND Flash

• QSPI implementation in 46nm process technology
• More than 10-years data retention
• 104MHz clock frequency that can support up to 52MB/S continuous data transfer rate

Space efficient packaging

• WSON8 6x8mm
• WSON8 5x6mm
• TFBGA24 6x8mm
• KGD (Known Good Die)