2022 marks the 35th anniversary of the invention of NAND flash memory. NOR Flash memory was invented by Dr. Fujio Masuoka while working for Toshiba in 1984. NOR-based flash has long erase and write times but has a full address/data (memory) interface that allows random access to any location. This makes it suitable for the storage of program code that needs to be infrequently updated, such as a computer’s BIOS or the firmware of set-top boxes. Its endurance is 10,000 to 1,000,000 erase cycles. NOR-based flash was the basis of early flash-based removable media; Compact Flash was originally based on it, though later cards moved to the cheaper NAND flash.

NAND flash was born out of a joint venture with Samsung and Toshiba and followed shortly thereafter. It has faster erase and write times, higher density, lower cost per bit than NOR flash, and ten times the endurance. However, it is most suitable for mass-storage devices such as PC cards and various memory cards because of its sequential write and is less useful for computer memory.

BPM has been around slightly longer than NAND Flash and has developed solutions for some of the particular challenges of programming flash devices. See the Flash white papers below.

Flash Memory White Papers