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hi, i want to know the difference between NOR and NAND

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guwen517

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in flash design , these two type have disadvantage and disadvantage ,can some one show me which is better for flash read and write speed??
thanks very much
 

manitooo

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For basic NAND flash and NOR flash here is a little summary

NOR :
Slow Write and Slow Erase....
Must Erase full block before write any single word into that block

Fast read :
Full asynch (allow radmon read of any single word into the memory)
Page read (asynchronous contiguous word read)
Burst read (synchronous fast read for contiguous words)

Usage : general for Code XIP (Execution in place)

NAND :

Fast write

allow only full page read (generaly 512 bytes)
We can find spare bytes in page (to improve Logical block, wearleveling and ECC)

Usage : generaly used for storage capability (mp3, jpg and so on)
 

ntfreak

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Here is a doc I got from Toshiba a while ago.

Regards
NTFreak
 

carrot

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hi

Nand is very best than Nor Gates Because in nand electron mobility is 2.5 times greater than nor gate
 

joc_06

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2 gate Nand's are the building blocks for pretty much all modern processors so says my professor and so every schematic we draw must be in 2 gate nand. i hate them!!

just my 2 cents
 

alphi

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It is two basic flash version:
Nor mostly use in 0-8Mbyte,and NAND use in 8-....
Nor is faster read speed than nand,but slower in write.
nand falsh almost use in store disk.
 

aegean.chou

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Renesas released AND flash, it's more fast than NAND in write, and it can be used in MP3 or Camera etc.
 

Black Jack

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NAND Flash typically have invalid blocks
(e.g. SAMSUNG K9K2GXXX0M, K9W4GXXU1M - 30 blocks)
and you must exclude them from read/write ops. by
some algorythms.

NAND - main for stream application (music, voice storage, etc.)

NOR Flash havn`t this trouble.
 

sabari

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Nand is very best than Nor Gates Because in nand electron mobility is 2.5 times greater than nor gate
 

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