M29W640FB STMICROELECTRONICS [STMicroelectronics], M29W640FB Datasheet - Page 16

• Manufacturer Part Number: M29W640FB
• Description: 64 Mbit (8Mb x8 or 4Mb x16, Page, Boot Block) 3V Supply Flash Memory
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

3 Bus operations
3.5
3.6
3.6.1
3.6.2
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Automatic Standby
Special Bus Operations
If CMOS levels (V
the memory enters Automatic Standby where the internal Supply Current is reduced to the
Standby Supply Current, I
operation is in progress.
Additional bus operations can be performed to read the Electronic Signature and also to apply
and remove Block Protection. These bus operations are intended for use by programming
equipment and are not usually used in applications. They require V
pins.
Electronic Signature
The memory has two codes, the manufacturer code and the device code, that can be read to
identify the memory. These codes can be read by applying the signals listed in
Operations, BYTE = VIL
Block Protect and Chip Unprotect
Groups of blocks can be protected against accidental Program or Erase. The Protection
Groups are shown in
be unprotected to allow the data inside the blocks to be changed.
The V
Write Protect is at V
regardless of the Block Protection Status or the Reset/Block Temporary Unprotect pin status.
Block Protect and Chip Unprotect operations are described in
PP
/Write Protect pin can be used to protect the two outermost boot blocks. When V
CC
IL
± 0.2V) are used to drive the bus and the bus is inactive for 300ns or more
Appendix A: Block addresses Table 20
the two outermost boot blocks are protected and remain protected
and
CC2
Table 4: Bus Operations, BYTE =
. The Data Inputs/Outputs will still output data if a Bus Read
and
Appendix D: Block
VIH.
M29W640FT, M29W640FB
Table
ID
to be applied to some
21. The whole chip can
Table 3: Bus
Protection.
PP
/