Samsung KFM4GH6Q4M, KFN8GH6Q4M, KFKAGH6Q4M warranty Locked-tight Nand Array Write Protection State

Models: KFN8GH6Q4M KFM4GH6Q4M KFKAGH6Q4M

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Flex-MuxOneNAND4G(KFM4GH6Q4M-DEBx)

 

Flex-MuxOneNAND8G(KFN8GH6Q4M-DEBx)

 

Flex-MuxOneNAND16G(KFKAGH6Q4M-DEBx)

FLASH MEMORY

3.4.3.3 Locked-tight NAND Array Write Protection State

A block that is in a locked-tight state can only be changed to locked state after a Cold or Warm Reset. Unlock and Lock command sequences will not affect its state. This is an added level of write protection security.

A block must first be set to a locked state before it can be changed to locked-tight using the Lock-tight command. locked-tight blocks will revert to a locked state following a Cold or Warm Reset.

When there are Lock-tight blocks in the flash array, All Block Unlock Command will fail and there will be no change in the lock status of the blocks of the Flash array.

Thus, All Block Unlock command succeeds only when there are no tightly-locked blocks in Flash.

Locked-tight

Lock-Tight Command Sequence:

Start block address+Lock-tight block command (002Ch)

3.4.4 NAND Flash Array Write Protection State Diagram

RP pin: High

&

Start block address Lock block Command or

Cold reset or Warm reset

unlock

Lock

unlock

Lock

RP pin: High

&

Start block address (000h) +All Block Unlock Command

RP pin: High

&

Start block address

+Unlock block Command

RP pin: High

&

Start block address +Lock-tight block Command

Lock

 

 

Power On

 

 

 

 

 

Cold reset or

Warm reset

Lock

Lock-tight

Lock

*NOTE : If the 1st Block is set to be OTP, Block 0 will always be Lock Status

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Page 62
Image 62
Samsung KFM4GH6Q4M warranty Locked-tight Nand Array Write Protection State, Nand Flash Array Write Protection State Diagram