M29F400BB STMICROELECTRONICS [STMicroelectronics], M29F400BB Datasheet - Page 14

• Manufacturer Part Number: M29F400BB
• Description: 4 Mbit (512Kb x8 or 256Kb x16, Boot Block) single supply Flash memory
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Bus operations
3.5
3.6
3.6.1
3.6.2
14/40
Automatic Standby
If CMOS levels (V
more the memory enters Automatic Standby where the internal Supply Current is reduced to
the CMOS Standby Supply Current, I
Bus Read operation is in progress.
Special bus operations
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
applied to some 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
and
Block Protection and Blocks Unprotection
Each block can be separately protected against accidental Program or Erase. Protected
blocks can be unprotected to allow data to be changed.
There are two methods available for protecting and unprotecting the blocks, one for use on
programming equipment and the other for in-system use. For further information refer to
Application Note AN1122, Applying Protection and Unprotection to M29 Series Flash.
Table 2.
1. X = V
Bus Read
Bus Write
Output Disable
Standby
Read Manufacturer
Code
Read Device Code
Table
Operation
IL
or V
3., Bus Operations.
IH
Bus operations, BYTE = V
.
CC
V
V
V
V
V
± 0.2V) are used to drive the bus and the bus is inactive for 150ns or
E
X
IH
IL
IL
IL
IL
V
V
V
V
V
G
X
IH
IH
IL
IL
IL
V
V
V
V
V
W
X
IH
IH
IH
IH
IL
CC3
Cell Address
Command Address
X
X
A0 = V
= V
A0 = V
= V
DQ15A–1, A0-A17
. The Data Inputs/Outputs will still output data if a
IL
Address Inputs
ID
ID
(1)
, Others V
, Others V
IL
IH
, A1 = V
, A1 = V
IL
IL
IL
IL
or V
or V
, A9
, A9
IH
IH
DQ14-DQ8
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
M29F400BT, M29F400BB
Data Inputs/Outputs
D5h (M29F400BT)
D6h (M29F400BB)
Data Output
Data Input
DQ7-DQ0
Hi-Z
Hi-Z
20h
ID
Table 2.
to be