SST39VF080-70-4I-EIET Silicon Storage Tech, SST39VF080-70-4I-EIET Datasheet - Page 3

• Manufacturer Part Number: SST39VF080-70-4I-EIET
• Description: Semiconductors and Actives, flash, Memory
• Manufacturer: Silicon Storage Tech

8 Mbit Multi-Purpose Flash
SST39LF080 / SST39VF080
The actual completion of the nonvolatile write is asynchro-
nous with the system; therefore, either a Data# Polling or
Toggle Bit read may be simultaneous with the completion
of the Write cycle. If this occurs, the system may possibly
get an erroneous result, i.e., valid data may appear to con-
flict with either DQ
rejection, if an erroneous result occurs, the software routine
should include a loop to read the accessed location an
additional two (2) times. If both reads are valid, then the
device has completed the Write cycle, otherwise the rejec-
tion is valid.
Data# Polling (DQ
When the SST39LF/VF080 are in the internal Program
operation, any attempt to read DQ
plement of the true data. Once the Program operation is
completed, DQ
though DQ
completion of an internal Write operation, the remaining
data outputs may still be invalid: valid data on the entire
data bus will appear in subsequent successive Read
cycles after an interval of 1 µs. During internal Erase opera-
tion, any attempt to read DQ
internal Erase operation is completed, DQ
‘1’. The Data# Polling is valid after the rising edge of fourth
WE# (or CE#) pulse for Program operation. For Sector-,
Block- or Chip-Erase, the Data# Polling is valid after the ris-
ing edge of sixth WE# (or CE#) pulse. See Figure 6 for
Data# Polling timing diagram and Figure 17 for a flowchart.
Toggle Bit (DQ
During the internal Program or Erase operation, any con-
secutive attempts to read DQ
and 0s, i.e., toggling between 1 and 0. When the internal
Program or Erase operation is completed, the DQ
stop toggling. The device is then ready for the next opera-
tion. The Toggle Bit is valid after the rising edge of fourth
WE# (or CE#) pulse for Program operation. For Sector-,
Block-, or Chip-Erase, the Toggle Bit is valid after the rising
edge of sixth WE# (or CE#) pulse. See Figure 7 for Toggle
Bit timing diagram and Figure 17 for a flowchart.
©2007 Silicon Storage Technology, Inc.
7
may have valid data immediately following the
7
will produce true data. Note that even
7
6
or DQ
)
7
)
6
. In order to prevent spurious
7
6
will produce a ‘0’. Once the
will produce alternating 1s
7
will produce the com-
7
will produce a
6
bit will
3
Data Protection
The SST39LF/VF080 provide both hardware and soft-
ware features to protect nonvolatile data from inadvertent
writes.
Hardware Data Protection
Noise/Glitch Protection: A WE# or CE# pulse of less than 5
ns will not initiate a Write cycle.
V
inhibited when V
Write Inhibit Mode: Forcing OE# low, CE# high, or WE#
high will inhibit the Write operation. This prevents inadvert-
ent writes during power-up or power-down.
Software Data Protection (SDP)
The SST39LF/VF080 provide the JEDEC approved Soft-
ware Data Protection scheme for all data alteration opera-
tions, i.e., Program and Erase. Any Program operation
requires the inclusion of the three-byte sequence. The
three-byte load sequence is used to initiate the Program
operation, providing optimal protection from inadvertent
Write operations, e.g., during the system power-up or
power-down. Any Erase operation requires the inclusion of
six-byte sequence. The SST39LF/VF080 devices are
shipped with the Software Data Protection permanently
enabled. See Table 4 for the specific software command
codes. During SDP command sequence, invalid com-
mands will abort the device to Read mode within T
Common Flash Memory Interface (CFI)
The SST39LF/VF080 also contain the CFI information to
describe the characteristics of the device. In order to enter
the CFI Query mode, the system must load the three-byte
sequence, similar to the Software ID Entry command. The
last byte cycle of this command loads 98H (CFI Query
command) to address 5555H. Once the device enters the
CFI Query mode, the system can read CFI data at the
addresses given in Tables 5 through 7. The system must
write the CFI Exit command to return to Read mode from
the CFI Query mode.
DD
Power Up/Down Detection: The Write operation is
DD
is less than 1.5V.
S71146-07-EOL
EOL Data Sheet
RC.
6/07