EN25F32 Datasheet, PDF (12/40 Pages) Eon Silicon Solution Inc. – 32 Megabit Serial Flash Memory with 4Kbytes Uniform Sector

EN25F32
Write Protection
Applications that use non-volatile memory must take into consideration the possibility of noise and other
adverse system conditions that may compromise data integrity. To address this concern the EN25F32
provides the following data protection mechanisms:
z Power-On Reset and an internal timer (tPUW) can provide protection against inadvertent changes
while the power supply is outside the operating specification.
z Program, Erase and Write Status Register instructions are checked that they consist of a number
of clock pulses that is a multiple of eight, before they are accepted for execution.
z All instructions that modify data must be preceded by a Write Enable (WREN) instruction to set
the Write Enable Latch (WEL) bit . This bit is returned to its reset state by the following events:
– Power-up
– Write Disable (WRDI) instruction completion or Write Status Register (WRSR) instruction
completion or Page Program (PP) instruction completion or Sector Erase (SE) instruction
completion or Block Erase (BE) instruction completion or Chip Erase (CE) instruction
completion
z The Block Protect (BP3, BP2, BP1, BP0) bits allow part of the memory to be configured as read-
only. This is the Software Protected Mode (SPM).
z The Write Protect (WP#) signal allows the Block Protect (BP2, BP1, BP0) bits and Status Register
Protect (SRP) bit to be protected. This is the Hardware Protected Mode (HPM).
z In addition to the low power consumption feature, the Deep Power-down mode offers extra
software protection from inadvertent Write, Program and Erase instructions, as all instructions are
ignored except one particular instruction (the Release from Deep Power-down instruction).
Table 3. Protected Area Sizes Sector Organization
Status Register Content
Memory Content
BP3 BP2
Bit Bit
0
0
0
0
0
0
0
0
0
1
0
1
0
1
0
1
1
0
1
0
1
0
1
0
1
1
1
1
1
1
1
1
BP1
Bit
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
BP0
Bit
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Protect Areas
Addresses
Density(KB) Portion
None
Block 0 to 62
Block 0 to 61
Block 0 to 59
Block 0 to 55
Block 0 to 47
Block 0 to 31
All
None
Block 63 to 1
Block 63 to 2
Block 63 to 4
Block 63 to 8
Block 63 to 16
Block 63 to 32
All
None
000000h-3EFFFFh
000000h-3DFFFFh
000000h-3BFFFFh
000000h-37FFFFh
000000h-2FFFFFh
000000h-1FFFFFh
000000h-3FFFFFh
None
3FFFFFh-010000h
3FFFFFh-020000h
3FFFFFh-040000h
3FFFFFh-080000h
3FFFFFh-100000h
3FFFFFh-200000h
000000h-3FFFFFh
None
4032KB
3968KB
3840KB
3584KB
3072KB
2048KB
4096KB
None
4032KB
3968KB
3840KB
3584KB
3072KB
2048KB
4096KB
None
Lower 63/64
Lower 62/64
Lower 60/64
Lower 56/64
Lower 48/64
Lower 32/64
All
None
Upper 63/64
Upper 62/64
Upper 60/64
Upper 56/64
Upper 48/64
Upper 32/64
All
This Data Sheet may be revised by subsequent versions
12 ^{©2004 Eon Silicon Solution, Inc.,}
or modifications due to changes in technical specifications.
Rev. G, Issue Date: 2009/10/16
www.eonssi.com