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M29W008AT, M29W008AB
SIGNAL DESCRIPTIONS
See Figure 1 and Table 1.
Address Inputs (A0-A19). The address inputs
for the memory array are latched during a write operation on the falling edge of Chip Enable E
or
Write Enable W
. When A9 is raised to VID, either a
Read Electronic Signature Manufacturer or Device
Code, Block Protection Status or a Write Block
Protection or Block Unprotection is enabled depending on the combinat ion of levels on A0, A1
A6, A12 and A15.
Data Input/Outputs (DQ0-DQ7). The input is
data to be programm ed in the memory array or a
command to be written to the C.I. Both are latched
on the rising edge of Chip Enable E or Write E nable W
. The output is data from the Memory Array,
the Electronic Signature Manufa cturer or Device
codes, the Block Prote ction Status or the Status
register Data Polling bit DQ7, the Toggle Bits DQ6
and DQ2, the Error bit DQ5 or the Erase Timer bit
DQ3. Outputs are valid when Chip Enable E
and
Output Enable G
are active. The output is high i mpedance when the chip is deselected or the outputs are disabled and when RP
is at a Low level.
Chip Enable (E
). The Chip Enable input acti-
vates the memory control logic, input buffers, decoders and sense amplifiers. E
High deselects the
memory and reduces the power consumption to
the stand-by level. E
can also b e used to control
writing to the command register and to the memory array, while W
remains at a low le v el. The Chip
Enable must be forced to V
ID
during the Block Un-
protection operation.
Output Enable (G
). The Output Enable gates the
outputs through the data buffers during a read operation. When G
is High the outpu ts are High im-
pedance. G
must be forced to VID level during
Block Protection and Unprotection operations.
Write Enable (W
). This input controls writing to
the Command Register and Address and Data
latches.
Ready/Busy Output (RB
). Ready/Busy is an
open-drain output and gives the internal state of
the P/E.C. of the device. When RB
is Low, the device is Busy with a Program or Erase operation
and it will not accept any additional program or
erase instructions except the Erase Suspend instruction.
When RB
is High, the device is ready for any
Read, Program or Erase operation. The RB
will
also be High when the memory is put in Erase
Suspend or Stand-by modes.
Reset/Block Temporary Unprotect Input (RP
).
The RP
Input provides hardware reset and protected block(s) temporary unprotection functions.
Reset of the memory is achieved by pulling RP
to
V
IL
for at least t
PLPX
. When the reset pulse is given, if the memory is in Read or Stand-by modes, it
will be available for new operations in t
PHEL
after
the rising edge of RP
.
If the memory is in Erase, Erase Suspend or Program modes the reset will take t
PLYH
during which
the R B
signal will be held at VIL. The end of the
memory re set will be indicate d by the risi ng edge
of RB
. A hardware reset d uring an Erase or Program operation will corrupt the data being programmed or the sector(s) being erased. See
Tables 15, 16 and Figure 8.
Temporary block unprotection is made by holding
RP
at VID. In this condi tion previously pro tected
blocks can be programmed or erased. The transition o f RP
from VIH to VID must slower than t
PH-
PHH
. (See Tables 17, 18 and Figure 8). When RP
is returned from VID to VIH all blocks temporarily
unprotected will be again protected.
V
CC
Supply Voltage. The power supply for all
operations (Read, Program and Erase).
V
SS
Ground. VSS is the reference for all voltage
measurements.