D A T A S H E E T
Program Operation
or Write-to-Buffer
Sequence in Progress
Write Program Suspend
Command Sequence
Write address/data
XXXh/B0h
Command is also valid for
Erase-suspended-program
operations
Wait 15 μs
Autoselect and SecSi Sector
read operations are also allowed
Read data as
required
Data cannot be read from erase- or
program-suspended sectors
Done
No
reading?
Yes
Write Program Resume
Command Sequence
Write address/data
XXXh/30h
Device reverts to
operation prior to
Program Suspend
Figure 6. Program Suspend/Program Resume
mediately terminates the erase operation. If that oc-
curs, the chip erase command sequence should be
reinitiated once the device has returned to reading
array data, to ensure data integrity. Note that the
SecSi Sector, autoselect, and CFI functions are un-
available when an erase operation is in progress.
Chip Erase Command Sequence
Chip erase is a six bus cycle operation. The chip erase
command sequence is initiated by writing two unlock
cycles, followed by a set-up command. Two additional
unlock write cycles are then followed by the chip erase
command, which in turn invokes the Embedded Erase
algorithm. The device does not require the system to
preprogram prior to erase. The Embedded Erase algo-
rithm automatically preprograms and verifies the entire
memory for an all zero data pattern prior to electrical
erase. The system is not required to provide any con-
trols or timings during these operations. Tables 10 and
11 show the address and data requirements for the
chip erase command sequence.
Figure 7 illustrates the algorithm for the erase opera-
tion. Refer to the Erase and Program Operations ta-
bles in the AC Characteristics section for parameters,
and Figure 19 section for timing diagrams.
Sector Erase Command Sequence
Sector erase is a six bus cycle operation. The sector
erase command sequence is initiated by writing two
unlock cycles, followed by a set-up command. Two ad-
ditional unlock cycles are written, and are then fol-
lowed by the address of the sector to be erased, and
the sector erase command. Tables 10 and 11 show the
address and data requirements for the sector erase
command sequence.
When the Embedded Erase algorithm is complete, the
device returns to the read mode and addresses are no
longer latched. The system can determine the status
of the erase operation by using DQ7, DQ6, or DQ2.
Refer to the Write Operation Status section for infor-
mation on these status bits.
The device does not require the system to preprogram
prior to erase. The Embedded Erase algorithm auto-
matically programs and verifies the entire memory for
Any commands written during the chip erase operation
are ignored. However, note that a hardware reset im-
30
Am29LV640MH/L
December 14, 2005
SPANSION [ SPANSION ]
