As many as 2% of the entire block is allowable (including the initial invalid block and the run-time invalid block). The 2% reservoir area of the blocks is set aside for replacement with invalid blocks as NAND. Therefore, the amount of available blocks to the user is all blocks minus the reservoir blocks.

It will lead to device failure. However, SAMSUNG guarantees that the device will operate during a 100K program/erase cycle without device failure caused by an increase of bad blocks.

SAMSUNG guarantees the first block will operate properly during the 100K P/E cycle under normal conditions. On the other hand, other blocks can be invalid as long as the total number of bad blocks doesn't exceed 2% of all blocks.

The first method is to screen out the initial bad block, and our process engineers utilize a complex technical method to guarantee it.

NOP is an acronym for the 'Number Of Partial programs'. It indicates how many times users can program on a single page. SAMSUNG guarantees 'NOP 8' on the 70nm and the 90nm products while 'NOP 4' is guaranteed on later products. NOP depends on the characteristic of the NAND core, and SAMSUNG cannot guarantee the exact value if users program multiple times on a page.

If the power is turned off during operations, the block or page that is in the process of being erased or programmed would be erased or programmed partially. All other blocks that are not in the process of being erased or programmed would be unaffected at all because it is isolated from the bit line and the common source line by a select transistor. Besides, partially programmed or erased blocks are managed by our software.

Erase operations are executed repeatedly until the operation is properly completed. This is handled by a specific algorithm of the SAMSUNG software