HY29F002T Datasheet, PDF (12/38 Pages) Hynix Semiconductor – 2 Megabit (256K x 8), 5 Volt-only, Flash Memory

HY29F002T
START
Issue PROGRAM
Command Sequence:
Last cycle contains
program Address/Data
START
Issue CHIP ERASE
Command Sequence
Check Programming Status
(See Write Operation Status
DQ[5] Error Exit
Section)
Normal Exit
NO
Last Word/Byte
Done?
YES
PROGRAMMING
COMPLETE
GO TO
ERROR RECOVERY
Figure 4. Programming Procedure
this state, and a succeeding read will show that
the data is still “0”.
Figure 4 illustrates the procedure for the Program
operation.
Chip Erase Command
The Chip Erase command sequence consists of
two unlock cycles, followed by the erase command,
two additional unlock cycles and then the chip erase
data cycle. During chip erase, all sectors of the
device are erased except protected sectors. The
command sequence starts the Automatic Erase al-
gorithm, which preprograms and verifies the entire
memory, except for protected sectors, for an all zero
data pattern prior to electrical erase. The device
then provides the required number of internally
generated erase pulses and verifies cell erasure
within the proper cell margins. The host system is
not required to provide any controls or timings dur-
ing these operations.
Commands written to the device during execution
of the Automatic Erase algorithm are ignored. Note
that a hardware reset immediately terminates the
erase operation. To ensure data integrity, the
aborted chip erase command sequence should be
reissued once the reset operation is complete.
When the Automatic Erase algorithm is finished,
the device returns to the Read mode. Several
methods are provided to allow the host to deter-
12
Check Erase Status
(See Write Operation Status
DQ[5] Error Exit
Section)
Normal Exit
CHIP ERASE COMPLETE
GO TO
ERROR RECOVERY
Figure 5. Chip Erase Procedure
mine the status of the erase operation, as de-
scribed in the Write Operation Status section.
Figure 5 illustrates the Chip Erase procedure.
Sector Erase Command
The Sector Erase command sequence consists
of two unlock cycles, followed by the erase com-
mand, two additional unlock cycles and then the
sector erase data cycle, which specifies which
sector is to be erased. As described later in this
section, multiple sectors can be specified for era-
sure with a single command sequence. During
sector erase, all specified sectors are erased se-
quentially. The data in sectors not specified for
erasure, as well as the data in any protected sec-
tors specified for erasure, is not affected by the
sector erase operation.
The Sector Erase command sequence starts the
Automatic Erase algorithm, which preprograms
and verifies the specified unprotected sectors for
an all zero data pattern prior to electrical erase.
The device then provides the required number of
internally generated erase pulses and verifies cell
erasure within the proper cell margins. The host
system is not required to provide any controls or
timings during these operations.
After the sector erase data cycle (the sixth bus
cycle) of the command sequence is issued, a sec-
tor erase time-out of 50 µs (minimum), measured
from the rising edge of the final WE# pulse in that
bus cycle, begins. During this time, an additional
sector erase data cycle, specifying the sector ad-
dress of another sector to be erased, may be writ-
ten into an internal sector erase buffer. This buffer
Rev. 4.1/May 01