SST39VF1601 データシートの表示（PDF） - Silicon Storage Technology
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SST39VF1601 Datasheet PDF : 31 Pages
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16 Mbit / 32 Mbit Multi-Purpose Flash Plus
SST39VF1601 / SST39VF3201
SST39VF1602 / SST39VF3202
Data Sheet
To resume Sector-Erase or Block-Erase operation which has
been suspended the system must issue Erase Resume
command. The operation is executed by issuing one byte
command sequence with Erase Resume command (30H)
at any address in the last Byte sequence.
Chip-Erase Operation
The SST39VF160x/320x provide a Chip-Erase operation,
which allows the user to erase the entire memory array to
the “1” state. This is useful when the entire device must be
quickly erased.
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 oper-
ation, any attempt to read DQ7 will produce a ‘0’. Once the
internal Erase operation is completed, DQ7 will produce a
‘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
rising edge of sixth WE# (or CE#) pulse. See Figure 7 for
Data# Polling timing diagram and Figure 21 for a flowchart.
The Chip-Erase operation is initiated by executing a six-
byte command sequence with Chip-Erase command
(10H) at address 5555H in the last byte sequence. The
Erase operation begins with the rising edge of the sixth
WE# or CE#, whichever occurs first. During the Erase
operation, the only valid read is Toggle Bit or Data# Polling.
See Table 6 for the command sequence, Figure 10 for tim-
ing diagram, and Figure 24 for the flowchart. Any com-
mands issued during the Chip-Erase operation are
ignored. When WP# is low, any attempt to Chip-Erase will
be ignored. During the command sequence, WP# should
be statically held high or low.
Write Operation Status Detection
The SST39VF160x/320x provide two software means to
detect the completion of a Write (Program or Erase) cycle,
in order to optimize the system write cycle time. The soft-
ware detection includes two status bits: Data# Polling
(DQ7) and Toggle Bit (DQ6). The End-of-Write detection
mode is enabled after the rising edge of WE#, which ini-
tiates the internal Program or Erase operation.
The actual completion of the nonvolatile write is asyn-
chronous with the system; therefore, either a Data# Poll-
ing 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 conflict with either DQ7 or DQ6. In order to pre-
vent spurious 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 rejection is valid.
Data# Polling (DQ7)
When the SST39VF160x/320x are in the internal Program
operation, any attempt to read DQ7 will produce the com-
plement of the true data. Once the Program operation is
completed, DQ7 will produce true data. Note that even
though DQ7 may have valid data immediately following the
Toggle Bits (DQ6 and DQ2)
During the internal Program or Erase operation, any con-
secutive attempts to read DQ6 will produce alternating “1”s
and “0”s, i.e., toggling between 1 and 0. When the internal
Program or Erase operation is completed, the DQ6 bit will
stop toggling. The device is then ready for the next opera-
tion. For Sector-, Block-, or Chip-Erase, the toggle bit (DQ6)
is valid after the rising edge of sixth WE# (or CE#) pulse.
DQ6 will be set to “1” if a Read operation is attempted on an
Erase-Suspended Sector/Block. If Program operation is ini-
tiated in a sector/block not selected in Erase-Suspend
mode, DQ6 will toggle.
An additional Toggle Bit is available on DQ2, which can be
used in conjunction with DQ6 to check whether a particular
sector is being actively erased or erase-suspended. Table 1
shows detailed status bits information. The Toggle Bit
(DQ2) is valid after the rising edge of the last WE# (or CE#)
pulse of Write operation. See Figure 8 for Toggle Bit timing
diagram and Figure 21 for a flowchart.
TABLE 1: Write Operation Status
Status
DQ7 DQ6
DQ2
Normal Standard
Operation Program
DQ7# Toggle No Toggle
Standard
Erase
0 Toggle Toggle
Erase- Read from
Suspend Erase-Suspended
Mode
Sector/Block
1
1
Toggle
Read from
Data
Non- Erase-Suspended
Sector/Block
Data
Data
Program
DQ7# Toggle
N/A
T1.0 1223
Note: DQ7 and DQ2 require a valid address when reading
status information.
©2008 Silicon Storage Technology, Inc.
3
S71223-05-000
6/08
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