AM29LV642D AMD [Advanced Micro Devices], AM29LV642D Datasheet - Page 22

• Manufacturer Part Number: AM29LV642D
• Manufacturer: AMD [Advanced Micro Devices]

Sector Group Protection and
Unprotection
The hardware sector group protection feature disables
both program and erase operations in any sector
group. In this device, a sector group consists of four
adjacent sectors that are protected or unprotected at
the same time (see Table 5). The hardware sector
group unprotection feature re-enables both program
and erase operations in previously protected sector
groups. Sector group protection/unprotection can be
implemented via two methods.
The primary method requires V
only, and can be implemented either in-system or via
programming equipment. Figure 2 shows the algo-
rithms and Figure 22 shows the timing diagram. This
method uses standard microprocessor bus cycle tim-
ing. For sector group unprotect, all unprotected sector
groups must first be protected prior to the first sector
group unprotect write cycle.
Some earlier 3.0 volt-only AMD flash devices used a
sector protection/unprotection method intended only
for programming equipment, and required V
dress pin A9 and OE#. If this earlier method is re-
quired for the intended application, contact AMD for
further details.
The device is shipped with all sector groups unpro-
tected. AMD offers the option of programming and pro-
tecting sector groups at its factory prior to shipping the
device through AMD’s ExpressFlash™ Service. Con-
tact an AMD representative for details.
It is possible to determine whether a sector group is
protected or unprotected. See the Autoselect Mode
section for details.
20
ID
on the RESET# pin
D A T A
ID
on ad-
Am29LV642D
S H E E T
Note: All sector groups are 128 Kwords in size.
Table 5. Sector Group Protection/Unprotection
SA100–SA103
SA104–SA107
SA108–SA111
SA112–SA115
SA116–SA119
SA120–SA123
SA124–SA127
Sector Group
SA12–SA15
SA16–SA19
SA20–SA23
SA24–SA27
SA28–SA31
SA32–SA35
SA36–SA39
SA40–SA43
SA44–SA47
SA48–SA51
SA52–SA55
SA56–SA59
SA60–SA63
SA64–SA67
SA68–SA71
SA72–SA75
SA76–SA79
SA80–SA83
SA84–SA87
SA88–SA91
SA92–SA95
SA96–SA99
SA8–SA11
SA0–SA3
SA4–SA7
Address Table
25022A2 May 5, 2006
A22–A18
00000
00001
00010
00011
00100
00101
00110
00111
01000
01001
01010
01011
01100
01101
01110
01111
10000
10001
10010
10011
10100
10101
10110
10111
11000
11001
11010
11011
11100
11101
11110
11111