MBM29DL640E Fujitsu Microelectronics, Inc., MBM29DL640E Datasheet - Page 26

• Manufacturer Part Number: MBM29DL640E
• Description: Flash Memory 64 M 8 M X 8/4 M X 16 Bit Dual Operation
• Manufacturer: Fujitsu Microelectronics, Inc.

26
MBM29DL640E
Sector Group Protection
Temporary Sector Group Unprotection
Extended Sector Group Protection
The device features hardware sector group protection. This feature will disable both program and erase opera-
tions in any combination of forty eight sector groups of memory. (See Table 7) . The user‘s side can use the
sector group protection using programming equipment. The device is shipped with all sector groups that are
unprotected.
To activate this mode, the programming equipment must force V
V
A
hundred forty-two (142) individual sectors, and Table 7 defines the sector group address for each of the forty
eight (48) individual group sectors. Programming of the protection circuitry begins on the falling edge of the WE
pulse and is terminated with the rising edge of the same. Sector group addresses must be held constant during
the WE pulse. See Figures 18 and 26 for sector group protection waveforms and algorithms.
To verify programming of the protection circuitry, the programming equipment must force V
with CE and OE at V
A
protected sector. Otherwise the device will produce “0” for unprotected sectors. In this mode, the lower order
addresses, except for A
Autoselect manufacturer and device codes. A
Whether the sector group is protected in the system can be determined by writing an Autoselect command.
Performing a read operation at the address location (BA) XX02h, where the higher order addresses (A
A
for a protected sector group. Note that the bank addresses (A
during the third write bus cycle of the Autoselect command. Then the Autoselect data can be read from that
bank while array data can still be read from the other bank. To read Autoselect data from the other bank, it must
be reset to read mode and then write the Autoselect command to the other bank. See Tables 5.1 and 5.2 for
Autoselect codes.
This feature allows temporary unprotection of previously protected sector groups of the device in order to change
data. The Sector Group Unprotection mode is activated by setting the RESET pin to high voltage (V
this mode, formerly protected sector groups can be programmed or erased by selecting the sector group ad-
dresses. Once the V
protected again. Refer to Figures 19 and 27.
In addition to normal sector group protection, the device has Extended Sector Group Protection as extended
function. This function enables protection of the sector group by forcing V
sequence. Unlike conventional procedures, it is not necessary to force V
The only RESET pin requires V
requires V
the command register. Then the sector group addresses pins (A
and (A
addresses pins is recommended) , and an extended sector group protection command (60h) should be written.
A sector group is typically protected in 250 s. To verify programming of the protection circuitry, the sector group
addresses pins (A
be set a command (40h) should be written. Following the command write, a logical “1” at device output DQ
produce a protected sector in the read operation. If the output is logical “0”, write the extended sector group
protection command (60h) again. To terminate the operation, it is necessary to set RESET pin to V
Figures 20 and 28.)
IL
12
13
19
) should be set to the sector to be protected. Tables 6.1 to 6.4 define the sector address for each of the one
, A
and A
and A
18
6
, A
, A
6
12
3
17
ID
, A
) while (A
, A
on RESET pin. With this condition the operation is initiated by writing the set-up command (60h) in
A
2
3
, A
16
, A
1
A
, A
21
2
15
, A
, A
0
6
IL
ID
)
, A
A
and WE at V
20
0
14
is taken away from the RESET pin, all the previously protected sector groups will be
0
3
, A
, A
, A
, A
(0, 0, 0, 1, 0) should be set to the sector group to be protected (setting V
V
19
1
13
2
, A
IL
, A
, A
, A
, and A
80/90/12
2
ID
18
1
, A
1
, A
, A
for sector group protection in this mode. The extended sector group protection
3
0
V
IH
17
)
and A
12
IH
. Scanning the sector group addresses (A
, A
. The sector group addresses (A
) are the desired sector group address, will produce a logical “1” at DQ
16
(0, 0, 0, 1, 0) will produce a logical “1” code at device output DQ
, A
6
are DON’T CARES. Address locations with A
15
-1
, A
requires applying to V
14
, A
13
and A
12
) and (A
21
, A
ID
21
, A
on address pin A
20
, A
20
IL
21
6
, A
on byte mode.
, A
ID
19
, A
) must be pointing to a specific bank
on RESET pin and writes a command
ID
19
3
20
, A
, A
and control timing for control pins.
, A
2
18
21
, A
19
, A
, A
, A
1
, A
17
20
18
9
, A
, A
, A
0
and control pin OE, CE
)
16
19
17
1
, A
, A
, A
(0, 0, 0, 1, 0) should
ID
18
15
V
16
on address pin A
, A
IL
, A
, A
are reserved for
17
14
15
IL
, A
, A
, A
for the other
IH
ID
16
13
14
. (Refer to
) . During
, A
, A
and A
21
15
13
0
, A
, A
for a
0
and
will
12
14
20
9
0
)
,
,