The SST39SF010A/020A/040 are CMOS Multi-Purpose
Flash (MPF) manufactured with SST’s proprietary, high
performance CMOS SuperFlash technology. The split-gate
cell design and thick oxide tunneling injector attain better
reliability and manufacturability compared with alternate
approaches. The SST39SF010A/020A/040 devices write
(Program or Erase) with a 4.5-5.5V power supply. The
SST39SF010A/020A/040 devices conform to JEDEC standard pinouts for x8 memories.
Featuring high performance Byte-Program, the
SST39SF010A/020A/040 devices provide a maximum
Byte-Program time of 20 µsec. These devices use Toggle
Bit or Data# Polling to indicate the completion of Program
operation. To protect against inadvertent write, they have
on-chip hardware and Software Data Protection schemes.
Designed, manufactured, and tested for a wide spectrum of
applications, these devices are offered with a guaranteed
typical endurance of 10,000 cycles. Data retention is rated
at greater than 100 years.
The SST39SF010A/020A/040 devices are suited for applications that require convenient and economical updating of
program, configuration, or data memory. For all system
applications, they significantly improve performance and
reliability, while lowering power consumption. They inherently use less energy during erase and program than alternative flash technologies. The total energy consumed is a
function of the applied voltage, current, and time of application. Since for any given voltage range, the SuperFlash
technology uses less current to program and has a shorter
erase time, the total energy consumed during any Erase or
Program operation is less than alternative flash technologies. These devices also improve flexibility while lowering
the cost for program, data, and configuration storage applications.
The SuperFlash technology provides fixed Erase and Program times, independent of the number of Erase/Program
cycles that have occurred. Therefore the system software
or hardware does not have to be modified or de-rated as is
necessary with alternative flash technologies, whose Erase
and Program times increase with accumulated Erase/Program cycles.
To meet high density, surface mount requirements, the
SST39SF010A/020A/040 are offered in 32-lead PLCC and
32-lead TSOP packages. A 600 mil, 32-pin PDIP is also
available. See Figures 1, 2, and 3 for pin assignments.
The SST logo and SuperFlash are registered trademarks of Silicon Storage Technology, Inc.
MPF is a trademark of Silicon Storage Technology, Inc.
These specifications are subject to change without notice.
Page 2
Data Sheet
1 Mbit / 2 Mbit / 4 Mbit Multi-Purpose Flash
SST39SF010A / SST39SF020A / SST39SF040
Device Operation
Commands are used to initiate the memory operation functions of the device. Commands are written to the device
using standard microprocessor write sequences. A command is written by asserting WE# low while keeping CE#
low. The address bus is latched on the falling edge of WE#
or CE#, whichever occurs last. The data bus is latched on
the rising edge of WE# or CE#, whichever occurs first.
Read
The Read operation of the SST39SF010A/020A/040 is
controlled by CE# and OE#, both have to be low for the
system to obtain data from the outputs. CE# is used for
device selection. When CE# is high, the chip is deselected and only standby power is consumed. OE# is the
output control and is used to gate data from the output
pins. The data bus is in high impedance state when
either CE# or OE# is high. Refer to the Read cycle timing
diagram (Figure 4) for further details.
Byte-Program Operation
The SST39SF010A/020A/040 are programmed on a byteby-byte basis. Before programming, the sector where the
byte exists must be fully erased. The Program operation is
accomplished in three steps. The first step is the three-byte
load sequence for Software Data Protection. The second
step is to load byte address and byte data. During the ByteProgram operation, the addresses are latched on the falling
edge of either CE# or WE#, whichever occurs last. The
data is latched on the rising edge of either CE# or WE#,
whichever occurs first. The third step is the internal Program operation which is initiated after the rising edge of the
fourth WE# or CE#, whichever occurs first. The Program
operation, once initiated, will be completed, within 20 µs.
See Figures 5 and 6 for WE# and CE# controlled Program
operation timing diagrams and Figure 15 for flowcharts.
During the Program operation, the only valid reads are
Data# Polling and Toggle Bit. During the internal Program
operation, the host is free to perform additional tasks. Any
commands written during the internal Program operation
will be ignored.
Sector-Erase Operation
The Sector-Erase operation allows the system to erase the
device on a sector-by-sector basis. The sector architecture
is based on uniform sector size of 4 KByte. The SectorErase operation is initiated by executing a six-byte command load sequence for Software Data Protection with
Sector-Erase command (30H) and sector address (SA) in
the last bus cycle. The sector address is latched on the falling edge of the sixth WE# pulse, while the command (30H)
is latched on the rising edge of the sixth WE# pulse. The
internal Erase operation begins after the sixth WE# pulse.
The End-of-Erase can be determined using either Data#
Polling or Toggle Bit methods. See Figure 9 for timing
waveforms. Any commands written during the SectorErase operation will be ignored.
Chip-Erase Operation
The SST39SF010A/020A/040 provide Chip-Erase operation, which allows the user to erase the entire memory
array to the “1s” state. This is useful when the entire device
must be quickly erased.
The Chip-Erase operation is initiated by executing a sixbyte Software Data Protection command sequence with
Chip-Erase command (10H) with address 5555H in the last
byte sequence. The internal Erase operation begins with
the rising edge of the sixth WE# or CE#, whichever occurs
first. During the internal Erase operation, the only valid read
is Toggle Bit or Data# Polling. See Table 4 for the command
sequence, Figure 10 for timing diagram, and Figure 18 for
the flowchart. Any commands written during the ChipErase operation will be ignored.
Write Operation Status Detection
The SST39SF010A/020A/040 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
software detection includes two status bits: Data# Polling
(DQ
) and Toggle Bit (DQ6). The End-of-Write detection
7
mode is enabled after the rising edge of WE# which initiates the internal Program or Erase operation.
The actual completion of the nonvolatile write is asynchronous 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 conflict 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 rejection is valid.
When the SST39SF010A/020A/040 are in the internal Program operation, any attempt to read DQ
will produce the
7
complement of the true data. Once the Program operation
is completed, DQ
though DQ
7
will produce true data. Note that even
7
may have valid data immediately following the
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 operation, any attempt to read DQ
internal Erase operation is completed, DQ
will produce a ‘0’. Once the
7
will produce a
7
‘1’. The Data# Polling is valid after the rising edge of fourth
WE# (or CE#) pulse for Program operation. For Sector- 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 16 for a flowchart.
Toggle Bit (DQ6)
During the internal Program or Erase operation, any consecutive attempts to read DQ
will produce alternating 0s
6
and 1s, i.e., toggling between 0 and 1. When the internal
Program or Erase operation is completed, the toggling will
stop. The device is then ready for the next operation. The
Toggle Bit is valid after the rising edge of fourth WE# (or
CE#) pulse for Program operation. For Sector- or ChipErase, the Toggle Bit is valid after the rising edge of sixth
WE# (or CE#) pulse. See Figure 8 for Toggle Bit timing diagram and Figure 16 for a flowchart.
Data Protection
The SST39SF010A/020A/040 provide both hardware and
software 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
Power Up/Down Detection: The Write operation is
DD
inhibited when V
Write Inhibit Mode:
high will inhibit the Write operation. This prevents inadvertent writes during power-up or power-down.
is less than 2.5V.
DD
Forcing OE# low, CE# high, or WE#
Software Data Protection (SDP)
The SST39SF010A/020A/040 provide the JEDEC
approved Software Data Protection scheme for all data
alteration operations, i.e., Program and Erase. Any Program operation requires the inclusion of a series of threebyte 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 load sequence. The SST39SF010A/
020A/040 devices are shipped with the Software Data Protection permanently enabled. See Table 4 for the specific
software command codes. During SDP command
sequence, invalid commands will abort the device to read
mode, within T
RC.
Product Identification
The Product Identification mode identifies the device as the
SST39SF040, SST39SF010A, or SST39SF020A and
manufacturer as SST. This mode may be accessed by software operations. Users may wish to use the software Product Identification operation to identify the part (i.e., using the
device ID) when using multiple manufacturers in the same
socket. For details, Table 4 for software operation, Figure
11 for the software ID entry and read timing diagram and
Figure 17 for the ID entry command sequence flowchart.
TABLE 1: P
Manufacturer’s ID0000HBFH
Device ID
SST39SF010A0001HB5H
SST39SF020A0001HB6H
SST39SF0400001HB7H
RODUCT IDENTIFICATION
AddressData
T1.2 1147
Product Identification Mode Exit/Reset
In order to return to the standard Read mode, the Software
Product Identification mode must be exited. Exit is accomplished by issuing the Exit ID command sequence, which
returns the device to the Read operation. Please note that
the software reset command is ignored during an internal
Program or Erase operation. See Table 4 for software command codes, Figure 12 for timing waveform and Figure 17
for a flowchart.
1. Address format A14-A0 (Hex), Addresses AMS-A15 can be VIL or VIH, but no other value, for the Command sequence.
A
= Most significant address
MS
= A16 for SST39SF010A, A17 for SST39SF020A, and A18 for SST39SF040
A
MS
2. BA = Program Byte address
3. SA
for Sector-Erase; uses AMS-A12 address lines
X
4. The device does not remain in Software Product ID mode if powered down.
5. With A
6. Both Software ID Exit operations are equivalent
4,5
6
6
= 0; SST Manufacturer’s ID = BFH, is read with A0 = 0,
MS-A1
1st Bus
Write Cycle
1
Addr
DataAddr1DataAddr1DataAddr1DataAddr1DataAddr1Data
2nd Bus
Write Cycle
3rd Bus
Write Cycle
5555HAAH2AAAH55H5555H90H
XXHF0H
5555HAAH2AAAH55H5555HF0H
SST39SF010A Device ID = B5H, is read with A
SST39SF020A Device ID = B6H, is read with A
SST39SF040 Device ID = B7H, is read with A
0
= 1
0
= 1
0
= 1
4th Bus
Write Cycle
2
Data
5th Bus
Write Cycle
6th Bus
Write Cycle
3
30H
X
T4.2 1147
Absolute Maximum Stress Ratings (Applied conditions greater than those listed under “Absolute Maximum
Stress Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation
of the device at these conditions or conditions greater than those defined in the operational sections of this data
sheet is not implied. Exposure to absolute maximum stress rating conditions may affect device reliability.)
Note: Toggle bit output is always high first.
AMS = Most significant address
AMS = A16 for SST39SF010A, A17 for SST39SF020A, and A18 for SST39SF040
FIGURE 8: TOGGLE BIT TIMING DIAGRAM
Note
T
CE
T
T
OET
TWO READ CYCLES
WITH SAME OUTPUTS
1147 F07.1
OES
SIX-BYTE CODE FOR SECTOR-ERASE
ADDRESS A
MS-0
55552AAA2AAA55555555
CE#
OE#
T
WP
WE#
DQ
7-0
SW0SW1SW2SW3SW4SW5
Note: This device also supports CE# controlled Sector-Erase operation. The WE# and CE# signals are
interchageable as long as minimum timings are met. (See Table 10)
SAX = Sector Address
AMS = Most significant address
AMS = A16 for SST39SF010A, A17 for SST39SF020A, and A18 for SST39SF040
Note: This device also supports CE# controlled Chip-Erase operation. The WE# and CE# signals are
interchageable as long as minimum timings are met. (See Table 10)
SAX = Sector Address
AMS = Most significant address
AMS = A16 for SST39SF010A, A17 for SST39SF020A, and A18 for SST39SF040