Displaced NOR Flash Finds New Uses
Gary Hilson | EE Times
The diminished use of NOR flash really boils down to its inability to scale, said Gregory Wong, principal analyst with Forward Insights, and for applications requiring one gigabyte and above. It’s expensive and there aren’t a lot options vendor-wise. A NAND option with an SPI interface makes a lot of sense for devices such as set-top boxes and televisions as they get even smarter and require more code.
But neither Kioxia’s Wong nor Forward Insights’ Wong sees NOR completely disappearing. The latter noted that as some applications outgrow NOR, others are popping up because the smaller density is enough for their needs. Many Internet of Things (IoT) devices can use it for code storage; and small devices such as wireless earbuds are opting for serial NOR, as are touch screen applications with finger sensors.
When the jump to NAND flash is necessary, SLC is optimal, said Gregory Wong, because it’s still a relatively small density, and as endurance and error corrections are critical for the applications involved, there’s no cost benefit to using MLC or TLC. “You get a lot of performance degradation and endurance degradation if you move to those capacities, so that's why they're sticking with SLC NAND,” added Gregory Wong.