MX29LV040C
READING ARRAY DATA
The device is automatically set to reading array data
after device power-up. No commands are required to
retrieve data. The device is also ready to read array data
after completing an Automatic Program or Automatic
Erase algorithm.
After the device accepts an Erase Suspend command,
the device enters the Erase Suspend mode. The sys-
tem can read array data using the standard read tim-
ings, except that if it reads at an address within erase-
suspended sectors, the device outputs status data. After
completing a programming operation in the Erase
Suspend mode, the system may once again read array
data with the same exception. See Erase Suspend/Erase
Resume Commands” for more infor-mation on this mode.
The system
must
issue the reset command to re-en-
able the device for reading array data if Q5 goes high, or
while in the autoselect mode. See the "Reset Command"
section, next.
SECTOR ERASE COMMANDS
The Automatic Sector Erase does not require the de-
vice to be entirely pre-programmed prior to executing
the Automatic Sector Erase Set-up command and Au-
tomatic Sector Erase command. Upon executing the
Automatic Sector Erase command, the device will auto-
matically program and verify the sector(s) memory for
an all-zero data pattern. The system is not required to
provide any control or timing during these operations.
When the sector(s) is automatically verified to contain
an all-zero pattern, a self-timed sector erase and verify
begin. The erase and verify operations are complete
when the data on Q7 is "1" and the data on Q6 stops
toggling for two consecutive read cycles, at which time
the device returns to the Read mode. The system is not
required to provide any control or timing during these
operations.
When using the Automatic sector Erase algorithm, note
that the erase automatically terminates when adequate
erase margin has been achieved for the memory array
(no erase verification command is required). Sector
erase is a six-bus cycle operation. There are two "un-
lock" write cycles. These are followed by writing the
set-up command 80H. Two more "unlock" write cycles
are then followed by the sector erase command 30H.
The sector address is latched on the falling edge of WE#
or CE#, whichever happens later, while the
command(data) is latched on the rising edge of WE# or
CE#, whichever happens first. Sector addresses se-
lected are loaded into internal register on the sixth fall-
ing edge of WE# or CE#, whichever happens later. Each
successive sector load cycle started by the falling edge
of WE# or CE#, whichever happens later must begin
within 50us from the rising edge of the preceding WE# or
CE#, whichever happens first. Otherwise, the loading
period ends and internal auto sector erase cycle starts.
(Monitor Q3 to determine if the sector erase timer win-
dow is still open, see section Q3, Sector Erase Timer.)
Any command other than Sector Erase(30H) or Erase
Suspend(B0H) during the time-out period resets the de-
vice to read mode.
RESET COMMAND
Writing the reset command to the device resets the
device to reading array data. Address bits are don't care
for this command.
The reset command may be written between the se-
quence cycles in an erase command sequence before
erasing begins. This resets the device to reading array
data. Once erasure begins, however, the device ignores
reset commands until the operation is complete.
The reset command may be written between the se-
quence cycles in a program command sequence be-fore
programming begins. This resets the device to reading
array data (also applies to programming in Erase
Suspend mode). Once programming begins, however,
the device ignores reset commands until the operation
is complete.
The reset command may be written between the se-
quence cycles in an SILICON ID READ command
sequence. Once in the SILICON ID READ mode, the
reset command
must
be written to return to reading array
data (also applies to SILICON ID READ during Erase
Suspend).
If Q5 goes high during a program or erase operation,
writing the reset command returns the device to read-
ing array data (also applies during Erase Suspend).
P/N:PM1149
REV. 1.3, APR. 24, 2006
10
MCNIX [ MACRONIX INTERNATIONAL ]
