EN25S80A Datasheet, PDF (9/66 Pages) Eon Silicon Solution Inc. – 8 Megabit 1.8V Serial Flash Memory with 4Kbyte Uniform Sector

EN25S80A
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 EN25S80A
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 (BP3, 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 15
Block 14 to 15
Block 12 to 15
Block 8 to 15
All
All
All
None
Block 0 to 14
Block 0 to 13
Block 0 to 11
Block 0 to 7
All
All
All
None
0F0000h-0FFFFFh
0E0000h-0FFFFFh
0C0000h-
0FFFFFh
080000h-0FFFFFh
000000h-0FFFFFh
000000h-0FFFFFh
000000h-0FFFFFh
None
000000h-0EFFFFh
000000h-0DFFFFh
000000h-0BFFFFh
000000h-07FFFFh
000000h-0FFFFFh
000000h-0FFFFFh
000000h-0FFFFFh
None
64KB
128KB
256KB
512KB
1024KB
1024KB
1024KB
None
960KB
896KB
768KB
512KB
1024KB
1024KB
1024KB
None
Upper 1/16
Upper 2/16
Upper 4/16
Upper 8/16
All
All
All
None
Lower 15/16
Lower 14/16
Lower 12/16
Lower 8/16
All
All
All
This Data Sheet may be revised by subsequent versions
9
or modifications due to changes in technical specifications.
©2014 Eon Silicon Solution, Inc.,
Rev. J, Issue Date: 2014/01/20
www.eonssi.com