512 Kbit / 1 Mbit / 2 Mbit / 4 Mbit 1.8V SPI Serial Flash
SST25WF512 / SST25WF010 / SST25WF020 / SST25WF040
Data Sheet
Block-Protection (BP2, BP1, BP0)
Block Protection Lock-Down (BPL)
The Block-Protection (BP1, BP0) bits define the size of the
memory area to be software protected against any mem-
ory Write (Program or Erase) operation, see Tables 5-7.
The Write-Status-Register (WRSR) instruction is used to
program the BP1 and BP0 bits as long as WP# is high or
the Block-Protect-Lock (BPL) bit is ‘0’. Chip-Erase can only
be executed if Block-Protection bits are all ‘0’. After power-
up, BP2, BP1, and BP0 are set to defaults. See Table 4 for
defaults at power-up.
When the WP# pin is driven low (VIL), it enables the Block-
Protection-Lock-Down (BPL) bit. When BPL is set to ‘1’, it
prevents any further alteration of the BPL, BP1, and BP0
bits. When the WP# pin is driven high (VIH), the BPL bit
has no effect and its value is ‘Don’t Care’. After power-up,
the BPL bit is reset to ‘0’.
TABLE 5: Software Status Register Block Protection for SST25WF512
Status Register Bit
Protected Memory Address
512 Kbit
Protection Level
None
BP11
BP0
0
0
1
1
0
1
0
1
None
1 (Upper Quarter Memory)
2 (Upper Half Memory)
3 (Full Memory)
00C000H-00FFFFH
008000H-00FFFFH
000000H-00FFFFH
T5.1 1328
T6.0 1328
T7.0 1328
1. Default at power-up for BP1 and BP0 is ‘11’.
TABLE 6: Software Status Register Block Protection for SST25WF010
Status Register Bit
Protected Memory Address
1 Mbit
Protection Level
None
BP11
BP0
0
0
1
1
0
1
0
1
None
1 (Upper Quarter Memory)
2 (Upper Half Memory)
3 (Full Memory)
018000H-01FFFFH
010000H-01FFFFH
000000H-01FFFFH
1. Default at power-up for BP1 and BP0 is ‘11’.
TABLE 7: Software Status Register Block Protection for SST25WF020
Status Register Bit
Protected Memory Address
2 Mbit
Protection Level
None
BP11
BP0
0
0
1
1
0
1
0
1
None
1 (Upper Quarter Memory)
2 (Upper Half Memory)
3 (Full Memory)
030000H-03FFFFH
020000H-03FFFFH
000000H-03FFFFH
1. Default at power-up for BP1 and BP0 is ‘11’.
©2009 Silicon Storage Technology, Inc.
S71328-08-000
11/09
8
SST [ SILICON STORAGE TECHNOLOGY, INC ]
