Flash memory controller

Some part of the spare cells is also used to hold the firmware which operates the controller and other special features for a particular storage device.

A directory structure is created to allow the controller to convert requests for logical sectors into the physical locations on the actual flash memory chips.

[citation needed] Flash memory can withstand a limited number of program-erase cycles.

[6] As the FTL metadata takes up its own flash space, it needs protection in case of power loss.

In addition, it is possible for the mapping table to wear out before other parts of the flash memory has, prematurely ending the life of a storage device.

This is usually avoided in enterprise devices by allocating an oversized space for spares, although more durable forms of storage like MRAM has been proposed for FTL too.

All SSDs, CF Cards, and other flash storage devices will include some level of garbage collection.