1.8” SATA SSD 3SE
15
Rev. 1.1 TPS, Jan. 2015
detection during read operation, is implemented on the fly without any decrease in performance.
3.4 Wear-Leveling
Flash memory can be only be erased a limited number of times. This number is called the
erase
cycle limit
or
write endurance
limit
and is defined by the NAND flash memory vendor. The
erase cycle limit applies to each individual block in the flash device.
Innodisk 1.8” SATA SSD 3SE uses a static wear-leveling algorithm to ensure that consecutive
writes of a specific sector are not written physically to the same page/block in the flash. This
spreads data usage evenly across all blocks while prolonging the lifecycle of the NAND flash
memory.
3.5 Bad Blocks Management
Bad Blocks are blocks that contain one or more invalid bits whose reliability are not guaranteed.
Bad Blocks may be present when the SSD is shipped, and may also develop over the lifetime of the
SSD. When Bad Blocks are detected, it will be flagged so that block will not be used anymore.
Bad Block management, Bad Block replacement, and Error Correcting Code are implemented to
avoid storing/accessing data errors. These functions are enabled automatically to transfer data
from Bad Blocks to spare blocks, and also correct error bits.
3.6 Power Cycling
Innodisk’s power cycling management is a complete data protection system that functions before
and after a sudden loss of power to Innodisk’s SSD. A Low-power detection circuit terminates
data writes before an abnormal power cycle. Once power is restored, table-remapping deletes
corrupted data to maintain data integrity. Innodisk’s power cycling management also prevents
data stored in flash from degrading overtime.
3.7 Garbage Collection/TRIM
Garbage collection and TRIM technology is used to maintain performance consistency by
continuously cleaning blocks marked for deletion on SSDs. The garbage collection runs as a
background process to have a minimal impact on the controller’s resources while combining valid
data into available blocks, and erasing blocks marked for deletion. This process also significantly
reduces write operations to the drive, thereby increasing the SSD’s lifespan.
