參數(shù)資料
型號: HY29F400BT-90
廠商: HYNIX SEMICONDUCTOR INC
元件分類: DRAM
英文描述: x8/x16 Flash EEPROM
中文描述: 256K X 16 FLASH 5V PROM, 90 ns, PDSO48
封裝: TSOP-48
文件頁數(shù): 9/40頁
文件大小: 509K
代理商: HY29F400BT-90
9
Rev. 5.2/May 01
HY29F400
The procedure for sector unprotection is illustrated
in the flow chart in Figure 2, and timing specifica-
tions and waveforms are given at the end of this
document.
Note that to unprotect any sector, all
unprotected sectors must first be protected prior
to the first unprotect write cycle.
Sectors can also be
temporarily
unprotected as
described in the next section.
Temporary Sector Unprotect Operation
This feature allows temporary unprotection of pre-
viously protected sectors to allow changing the
data in-system. Temporary Sector Unprotect
mode is activated by setting the RESET# pin to
V
ID
. While in this mode, formerly protected sec-
tors can be programmed or erased by invoking
the appropriate commands (see Device Com-
mands section). Once V
ID
is removed from RE-
SET#, all the previously protected sectors are pro-
tected again. Figure 3 illustrates the algorithm.
START
NOTE: All sectors must be
previously protected.
Set: TRYCNT = 1
Set: A[9] = CE# = OE# = V
ID
Set: RESET# = V
IH
WE# = V
IL
Wait t
WPP2
Set:
A[9] = V
OE# = CE# = V
IL
Read Data
Data = 0x00
NSEC = 10
YES
TRYCNT = 1000
NO
Increment TRYCNT
NO
YES
DEVICE FAILURE
NO
YES
Remove V
ID
from A[9]
SECTOR UNPROTECT
COMPLETE
APPLY V
CC
Set Sector Address:
A[17:12] = Sector NSEC
A[0] = A[6] = V
A[1] = V
IH
IL
NSEC = NSEC + 1
Set: NSEC = 0
WE# = V
IH
Figure 2. Sector Unprotect Procedure
START
RESET# = V
(All protected sector groups
become unprotected)
Perform Program or Erase
Operations
RESET# = V
(All previously protected
sector groups return to
protected state)
TEMPORARY SECTOR
UNPROTECT COMPLETE
Figure 3. Temporary Sector Unprotect
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HY29F400TG45 制造商:HYNIX 制造商全稱:Hynix Semiconductor 功能描述:4 Megabit (512Kx8/256Kx16) 5 Volt-only Flash Memory
HY29F400TG-45 制造商:HYNIX 制造商全稱:Hynix Semiconductor 功能描述:x8/x16 Flash EEPROM
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HY29F400TG-55 制造商:HYNIX 制造商全稱:Hynix Semiconductor 功能描述:x8/x16 Flash EEPROM
HY29F400TG70 制造商:HYNIX 制造商全稱:Hynix Semiconductor 功能描述:4 Megabit (512Kx8/256Kx16) 5 Volt-only Flash Memory