K9F5608D0D SAMSUNG [Samsung semiconductor], K9F5608D0D Datasheet - Page 15

• Manufacturer Part Number: K9F5608D0D
• Description: 32M x 8 Bit NAND Flash Memory
• Manufacturer: SAMSUNG [Samsung semiconductor]

NAND Flash Technical Notes
Initial Invalid Block(s)
Initial invalid blocks are defined as blocks that contain one or more initial invalid bits whose reliability is not guaranteed by Samsung.
The information regarding the initial invalid block(s) is so called as the initial invalid block information. Devices with initial invalid
block(s) have the same quality level as devices with all valid blocks and have the same AC and DC characteristics. An initial invalid
block(s) does not affect the performance of valid block(s) because it is isolated from the bit line and the common source line by a
select transistor. The system design must be able to mask out the invalid block(s) via address mapping. The 1st block, which is
placed on 00h block address, is guaranteed to be a valid block, does not require Error Correction
Identifying Initial Invalid Block(s)
All device locations are erased(FFh) except locations where the initial invalid block(s) information is written prior to shipping. The
initial invalid block(s) status is defined by the 6th byte in the spare area. Samsung makes sure that either the 1st or 2nd page of every
initial invalid block has non-FFh data at the column address of 517. Since the initial invalid block information is also erasable in most
cases, it is impossible to recover the information once it has been erased. Therefore, the system must be able to recognize the initial
invalid block(s) based on the initial invalid block information and create the initial invalid block table via the following suggested flow
chart(Figure 3). Any intentional erasure of the initial invalid block information is prohibited.
K9F5608R0D
K9F5608U0D
Increment Block Address
Invalid Block(s) Table
Create (or update)
K9F5608D0D
Initial
Figure 3. Flow chart to create initial invalid block table.
No
No
Set Block Address = 0
Check "FFh" ?
Last Block ?
15
Start
End
Yes
Yes
*
Check "FFh" at the column address
517of the 1st and 2nd page in the block
up to 1K Program/Erase cycles.
FLASH MEMORY