Apple Said to Be Stopping Use of TLC NAND Flash in iPhone 6 and 6 Plus After Reported Issues

Apple will switch from using TLC (triple-level cell) NAND flash to MLC (multi-level cell) NAND flash in the iPhone 6 and iPhone 6 Plus after users have experienced crashing and boot loop issues with the higher capacity versions of both devices, reports BusinessKorea.

Sources have told the paper that flash memory firm Anobit, which Apple acquired in 2011, is to blame for the manufacturing defects. Apple will reportedly switch to MLC NAND flash for the 64GB iPhone 6 and the 128GB iPhone 6 Plus, and will also address crashing and boot loop issues with the release of iOS 8.1.1. Apple has used MLC NAND flash before, in previous-generation iPhones.

TLC NAND flash is a type of solid-state NAND flash memory that stores three bits of data per cell. It can store three times as much data as single-level cell (SLC) that stores one bit of data, and 1.5 times as much as multi-level cell (MLC) solid-state flash memory that stores two bits of data. On top of that, TLC flash is more affordable. However, it is also slower than SLC or MLC in reading and writing data.

Apple released its first iOS 8.1.1 beta to developers earlier this week, although the company did not specify whether the included bug fixes addressed boot loop and crashing issues on the iPhone 6 and iPhone 6 Plus. Users who are experiencing an unusual amount of boot loops and crashes with their iPhone 6 or iPhone 6 Plus are recommended to bring their devices back to an Apple Retail Store for a replacement.