TLC or MLC on iPhone 6 and iPhone 6 Plus Which one is Faster?

Since iPhone 6 and iPhone 6 Plus was released, there are a lot of complaints from the user saying that the devices will reboot suddenly or freeze suddenly. However, fortunately, this does not happen to all the devices released in the market but only to some units out there in the market.

One of the reasons of this is that certain iPhone 6 and iPhone 6 Pluses is using TLC NAND flash whereas the rest is using MLC NAND flash. The difference is that TLC (Triple Level Cell) is generally slower than MLC (Multi Level Cell) but it can store 1.5 times as much data as MLC. This makes TLC cheaper to produce.

However, some guys over at KBench in Korea recently benchmarked 64GB iPhone 6 with TLC and MLC in quest to determine their behavior difference.  The first test that they did is Zero Filling. It is basically a way to overwrite all the data on the storage device with null values (0x00). This will permanently remove data stored in the device and it cannot be retrieved. The data amount that is being written is of 3.4GB. It turns out that MLC NAND flash maintained the transfer rate at 75MB/s for most part of the benchmark whereas the TLC has a higher transfer rate at 200MB/s but until around 26MB mark, it started to drop to about 49MB/s when the data amount being transferred reached about 800 MB.

The end result is that MLC is superior to TLC and Apple should have used MLC to product iPhone 6 and iPhone 6 Plus in order to eliminate these inconveniences.  However, rumors have it that Apple will discontinue the use of TLC NAND flash and hopefully it will improve the performance of iPhone 6 and iPhone 6 Plus.

TLC or MLC on iPhone 6 and iPhone 6 Plus Which one is Faster?

Apple to Stop Using TLC NAND Flash for iPhone 6 and iPhone 6 Plus

We had heard news about iPhone 6 and iPhone 6 plus issues ever since it has been released earlier this year. For unknown reasons, the handsets would just freeze up on their owners, or even worse, enter a boot loop. After checking on the issue thoroughly, it was found out that the culprit is might be TLC NAND flash memory.

TLC NAND flash is a solid state type of 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). MLC is a solid state flash memory that stores two bits of data. This makes TLC flash more affordable. However, TLC is also slower than SLC or MLC in reading and writing data.

Apparently, Apple has decided to stop using the TLC NAND and replacing it with MLC NAND. MLC NAND is used in 16GB version of iPhone 6 and iPhone 6 Plus and some 64GB models but the LC NAND was used in all of the 128GB models. TLC NAND was used apparently to reduce costs. To our surprise, some iPads previously is also using TLC NAND.

As the complaints from iPhone 6 and iPhone 6 plus is increasing, some users posts in online communities on possible requests to replace the product due to slow speeds.  Therefore, it is getting popular among user to find out whether their device is using MLC and TLC NAND through speed measurement. There is also speculation to a potential recall of iPhone 6 plus since there is technical defects which mainly occur in 128GB version of iPhone 6 Plus as there might be issue in triple-level cell (TLC) NAND flash.

Apple to Stop Using TLC NAND Flash for iPhone 6 and iPhone 6 Plus