AS5F Serial Peripheral Interface (SPI) NAND Flash Alliance Memory AS5F Serial Peripheral Interface (SPI) NAND Flash are memory devices with Single-Level Cell (SLC) NAND of the standard parallel NAND. These devices operate from 1.8V to 3V with densities from 1Gb to 8Gb and high-speed clock frequencies up to 120MHz. The AS5F SPI NAND flash devices offer increased reliability, faster boot-up, and more than 60,000 write and erase cycles in a smaller form factor. These devices provide a low-cost and low pin count solution to alternate SPI-NOR in high-density, non-volatile memory storage solutions for embedded systems. The AS5F SPI NAND flash devices feature 64x pages of one-time programmable protection, where each page consists of a data storage region and a spare area. The data storage region stores user-programmed data, and the spare area is typically used for memory management and error correction functions.