2 Mbit (256K x8) Page-Mode EEPROM
SST29EE020 / SST29LE020 / SST29VE020
SST29EE020 / SST29LE020 / SST29VE0202 Mb Page-Mode flash memories
Data Sheet
FEATURES:
• Single Voltage Read and Write Operations
– 5.0V-only for SST29EE020
– 3.0-3.6V for SST29LE020
– 2.7-3.6V for SST29VE020
• Superior Reliability
– Endurance: 100,000 Cycles (typical)
– Greater than 100 years Data Retention
• Low Power Consumption
– Active Current: 20 mA (typical) for 5V and
10 mA (typical) for 3.0/2.7V
– Standby Current: 10 µA (typical)
• Fast Page-Write Operation
– 128 Bytes per Page, 2048 Pages
– Page-Write Cycle: 5 ms (typical)
– Complete Memory Rewrite: 10 sec (typical)
– Effective Byte-Write Cycle Time: 39 µs (typical)
• Fast Read Access Time
– 5.0V-only operation: 120 and 150 ns
– 3.0-3.6V operation: 200 and 250 ns
– 2.7-3.6V operation: 200 and 250 ns
• Latched Address and Data
• Automatic Write Timing
– Internal V
PP
Generation
• End of Write Detection
– Toggle Bit
– Data# Polling
• Hardware and Software Data Protection
• Product Identification can be accessed via
Software Operation
• TTL I/O Compatibility
• JEDEC Standard
– Flash EEPROM Pinouts and command sets
• Packages Available
– 32-lead PLCC
– 32-lead TSOP (8mm x 14mm, 8mm x 20mm)
– 32-pin PDIP
PRODUCT DESCRIPTION
The SST29EE/LE/VE020 are 256K x8 CMOS Page-Write
EEPROM manufactured with SST’s proprietary, high per-
formance CMOS SuperFlash technology. The split-gate
cell design and thick oxide tunneling injector attain better
reliability and manufacturability compared with alternate
approaches. The SST29EE/LE/VE020 write with a single
power supply. Internal Erase/Program is transparent to the
user. The SST29EE/LE/VE020 conform to JEDEC stan-
dard pinouts for byte-wide memories.
Featuring high performance Page-Write, the SST29EE/LE/
VE020 provide a typical Byte-Write time of 39 µsec. The
entire memory, i.e., 256 KBytes, can be written page-by-
page in as little as 10 seconds, when using interface fea-
tures such as Toggle Bit or Data# Polling to indicate the
completion of a Write cycle. To protect against inadvertent
write, the SST29EE/LE/VE020 have on-chip hardware and
Software Data Protection schemes. Designed, manufac-
tured, and tested for a wide spectrum of applications, the
SST29EE/LE/VE020 are offered with a guaranteed Page-
Write endurance of 10,000 cycles. Data retention is rated at
greater than 100 years.
The SST29EE/LE/VE020 are suited for applications that
require convenient and economical updating of program,
configuration, or data memory. For all system applications,
the SST29EE/LE/VE020 significantly improve performance
and reliability, while lowering power consumption. The
SST29EE/LE/VE020 improve flexibility while lowering the
cost for program, data, and configuration storage applica-
tions.
To meet high density, surface mount requirements, the
SST29EE/LE/VE020 are offered in 32-lead PLCC and 32-
lead TSOP packages. A 600-mil, 32-pin PDIP package is
also available. See Figures 1, 2, and 3 for pinouts.
Device Operation
The SST Page-Mode EEPROM offers in-circuit electrical
write capability. The SST29EE/LE/VE020 does not require
separate Erase and Program operations. The internally
timed Write cycle executes both erase and program trans-
parently to the user. The SST29EE/LE/VE020 have indus-
try standard optional Software Data Protection, which SST
recommends always to be enabled. The SST29EE/LE/
VE020 are compatible with industry standard EEPROM
pinouts and functionality.
©2001 Silicon Storage Technology, Inc.
S71062-06-000 6/01
307
1
The SST logo and SuperFlash are registered trademarks of Silicon Storage Technology, Inc.
SSF is a trademark of Silicon Storage Technology, Inc.
These specifications are subject to change without notice.
2 Mbit Page-Mode EEPROM
SST29EE020 / SST29LE020 / SST29VE020
Data Sheet
Read
The Read operations of the SST29EE/LE/VE020 are con-
trolled 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 for further details
(Figure 4).
consists of a specific three-byte load sequence that allows
writing to the selected page and will leave the SST29EE/
LE/VE020 protected at the end of the Page-Write. The
page load cycle consists of loading 1 to 128 Bytes of data
into the page buffer. The internal Write cycle consists of the
T
BLCO
time-out and the write timer operation. During the
Write operation, the only valid reads are Data# Polling and
Toggle Bit.
The Page-Write operation allows the loading of up to 128
bytes of data into the page buffer of the SST29EE/LE/
VE020 before the initiation of the internal Write cycle. Dur-
ing the internal Write cycle, all the data in the page buffer is
written simultaneously into the memory array. Hence, the
Page-Write feature of SST29EE/LE/VE020 allow the entire
memory to be written in as little as 10 seconds. During the
internal Write cycle, the host is free to perform additional
tasks, such as to fetch data from other locations in the sys-
tem to set up the write to the next page. In each Page-Write
operation, all the bytes that are loaded into the page buffer
must have the same page address, i.e. A
7
through A
16
. Any
byte not loaded with user data will be written to FFH.
See Figures 5 and 6 for the Page-Write cycle timing dia-
grams. If after the completion of the three-byte SDP load
sequence or the initial byte-load cycle, the host loads a sec-
ond byte into the page buffer within a byte-load cycle time
(T
BLC
) of 100 µs, the SST29EE/LE/VE020 will stay in the
page load cycle. Additional bytes are then loaded consecu-
tively. The page load cycle will be terminated if no addi-
tional byte is loaded into the page buffer within 200 µs
(T
BLCO
) from the last byte-load cycle, i.e., no subsequent
WE# or CE# high-to-low transition after the last rising edge
of WE# or CE#. Data in the page buffer can be changed by
a subsequent byte-load cycle. The page load period can
continue indefinitely, as long as the host continues to load
the device within the byte-load cycle time of 100 µs. The
page to be loaded is determined by the page address of
the last byte loaded.
Write
The Page-Write to the SST29EE/LE/VE020 should always
use the JEDEC Standard Software Data Protection (SDP)
three-byte command sequence. The SST29EE/LE/VE020
contain the optional JEDEC approved Software Data Pro-
tection scheme. SST recommends that SDP always be
enabled, thus, the description of the write operations will be
given using the SDP enabled format. The three-byte SDP
Enable and SDP Write commands are identical; therefore,
any time a SDP Write command is issued, Software Data
Protection is automatically assured. The first time the three-
byte SDP command is given, the device becomes SDP
enabled. Subsequent issuance of the same command
bypasses the data protection for the page being written. At
the end of the desired Page-Write, the entire device
remains protected. For additional descriptions, please see
the application notes
The Proper Use of JEDEC Standard
Software Data Protection
and
Protecting Against Uninten-
tional Writes When Using Single Power Supply Flash
Memories.
The Write operation consists of three steps. Step 1 is the
three-byte load sequence for Software Data Protection.
Step 2 is the byte-load cycle to a page buffer of the
SST29EE/LE/VE020. Steps 1 and 2 use the same timing
for both operations. Step 3 is an internally controlled Write
cycle for writing the data loaded in the page buffer into the
memory array for nonvolatile storage. During both the SDP
three-byte load sequence and the byte-load cycle, the
addresses are latched by the falling edge of either CE# or
WE#, whichever occurs last. The data is latched by the ris-
ing edge of either CE# or WE#, whichever occurs first. The
internal Write cycle is initiated by the T
BLCO
timer after the
rising edge of WE# or CE#, whichever occurs first. The
Write cycle, once initiated, will continue to completion, typi-
cally within 5 ms. See Figures 5 and 6 for WE# and CE#
controlled Page-Write cycle timing diagrams and Figures
15 and 17 for flowcharts.
The Write operation has three functional cycles: the Soft-
ware Data Protection load sequence, the page load cycle,
and the internal Write cycle. The Software Data Protection
©2001 Silicon Storage Technology, Inc.
Software Chip-Erase
The SST29EE/LE/VE020 provide a Chip-Erase operation,
which allows the user to simultaneously clear the entire
memory array to the “1” state. This is useful when the entire
device must be quickly erased.
The Software Chip-Erase operation is initiated by using a
specific six-byte load sequence. After the load sequence,
the device enters into an internally timed cycle similar to the
Write cycle. During the Erase operation, the only valid read
is Toggle Bit. See Table 4 for the load sequence, Figure 10
for timing diagram, and Figure 19 for the flowchart.
S71062-06-000 6/01
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2
2 Mbit Page-Mode EEPROM
SST29EE020 / SST29LE020 / SST29VE020
Data Sheet
Write Operation Status Detection
The SST29EE/LE/VE020 provide two software means to
detect the completion of a Write cycle, in order to optimize
the system Write cycle time. The software detection
includes two status bits: Data# Polling (DQ
7
) and Toggle Bit
(DQ
6
). The end of write detection mode is enabled after the
rising WE# or CE# whichever occurs first, which initiates
the internal Write cycle.
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
7
or DQ
6
. In order to prevent 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 rejec-
tion is valid.
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 SST29EE/LE/VE020 provide the JEDEC approved
optional Software Data Protection scheme for all data alter-
ation operations, i.e., Write and Chip-Erase. With this
scheme, any Write operation requires the inclusion of a
series of three byte-load operations to precede the data
loading operation. The three byte-load sequence is used to
initiate the Write cycle, providing optimal protection from
inadvertent write operations, e.g., during the system power-
up or power-down. The SST29EE/LE/VE020 are shipped
with the Software Data Protection disabled.
The software protection scheme can be enabled by apply-
ing a three-byte sequence to the device, during a page-
load cycle (Figures 5 and 6). The device will then be auto-
matically set into the data protect mode. Any subsequent
Write operation will require the preceding three-byte
sequence. See Table 4 for the specific software command
codes and Figures 5 and 6 for the timing diagrams. To set
the device into the unprotected mode, a six-byte sequence
is required. See Table 4 for the specific codes and Figure 9
for the timing diagram. If a write is attempted while SDP is
enabled the device will be in a non-accessible state for
~300 µs. SST recommends Software Data Protection
always be enabled. See Figure 17 for flowcharts.
The SST29EE/LE/VE020 Software Data Protection is a
global command, protecting all pages in the entire memory
array once enabled (or disabled). Therefore using SDP for
a single Page-Write will enable SDP for the entire array.
Single pages by themselves cannot be SDP enabled or
disabled.
Single power supply reprogrammable nonvolatile memo-
ries may be unintentionally altered. SST strongly recom-
mends that Software Data Protection (SDP) always be
enabled. The SST29EE/LE/VE020 should be programmed
using the SDP command sequence. SST recommends the
SDP Disable Command Sequence not be issued to the
device prior to writing.
Please refer to the following Application Notes for more
information on using SDP:
•
•
Protecting Against Unintentional Writes When
Using Single Power Supply Flash Memories
The Proper Use of JEDEC Standard Software
Data Protection
Data# Polling (DQ
7
)
When the SST29EE/LE/VE020 are in the internal Write
cycle, any attempt to read DQ
7
of the last byte loaded dur-
ing the byte-load cycle will receive the complement of the
true data. Once the Write cycle is completed, DQ
7
will
show true data. The device is then ready for the next opera-
tion. See Figure 7 for Data# Polling timing diagram and Fig-
ure 16 for a flowchart.
Toggle Bit (DQ
6
)
During the internal Write cycle, any consecutive attempts to
read DQ
6
will produce alternating 0s and 1s, i.e., toggling
between 0 and 1. When the Write cycle is completed, the
toggling will stop. The device is then ready for the next
operation. See Figure 8 for Toggle Bit timing diagram and
Figure 16 for a flowchart. The initial read of the Toggle Bit
will typically be a “1”.
Data Protection
The SST29EE/LE/VE020 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
DD
Power Up/Down Detection: The Write operation is
inhibited when V
DD
is less than 2.5V.
©2001 Silicon Storage Technology, Inc.
S71062-06-000 6/01
307
3
2 Mbit Page-Mode EEPROM
SST29EE020 / SST29LE020 / SST29VE020
Data Sheet
Product Identification
The product identification mode identifies the device as the
SST29EE/LE/VE020 and manufacturer as SST. This mode
is accessed via software. For details, see Table 4, Figure
11 for the software ID entry and read timing diagram, and
Figure 18 for the ID entry command sequence flowchart.
TABLE 1: P
RODUCT
I
DENTIFICATION
Address
Manufacturer’s ID
Device ID
SST29EE020
SST29LE020
SST29VE020
0001H
0001H
0001H
10H
12H
12H
T1.3 307
Product Identification Mode Exit
In order to return to the standard read mode, the Software
Product Identification mode must be exited. Exiting is
accomplished by issuing the Software ID Exit (reset) opera-
tion, which returns the device to the Read operation. The
Reset operation may also be used to reset the device to the
Read mode after an inadvertent transient condition that
apparently causes the device to behave abnormally, e.g.,
not read correctly. See Table 4 for software command
codes, Figure 12 for timing waveform, and Figure 18 for a
flowchart.
Data
BFH
0000H
F
UNCTIONAL
B
LOCK
D
IAGRAM
X-Decoder
SuperFlash
Memory
A17 - A0
Address Buffer & Latches
Y-Decoder and Page Latches
CE#
OE#
WE#
Control Logic
I/O Buffers and Data Latches
DQ7 - DQ0
307 ILL B1.1
WE#
VDD
A12
A15
A16
A7
A6
A5
A4
A3
A2
A1
A0
DQ0
5
6
7
8
9
10
11
12
13
4
3
2
1
32 31 30
29
28
27
26
25
24
23
22
A17
NC
A14
A13
A8
A9
A11
OE#
A10
CE#
DQ7
32-lead PLCC
Top View
21
14 15 16 17 18 19 20
DQ1
DQ2
VSS
DQ3
DQ4
DQ5
DQ6
307 ILL F02.3
FIGURE 1: P
IN
A
SSIGNMENTS FOR
32-
LEAD
PLCC
©2001 Silicon Storage Technology, Inc.
S71062-06-000 6/01
307
4
2 Mbit Page-Mode EEPROM
SST29EE020 / SST29LE020 / SST29VE020
Data Sheet
A11
A9
A8
A13
A14
A17
WE#
VDD
NC
A16
A15
A12
A7
A6
A5
A4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
OE#
A10
CE#
DQ7
DQ6
DQ5
DQ4
DQ3
VSS
DQ2
DQ1
DQ0
A0
A1
A2
A3
307 ILL F01.2
Standard Pinout
Top View
Die Up
FIGURE 2: P
IN
A
SSIGNMENTS FOR
32-
LEAD
TSOP
NC
A16
A15
A12
A7
A6
A5
A4
A3
A2
A1
A0
DQ0
DQ1
DQ2
VSS
1
2
3
4
5
32-pin
6
PDIP
7
8
Top View
9
10
11
12
13
14
15
16
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
VDD
WE#
A17
A14
A13
A8
A9
A11
OE#
A10
CE#
DQ7
DQ6
DQ5
DQ4
DQ3
307 ILL F19.0
FIGURE 3: P
IN
A
SSIGNMENTS FOR
32-
PIN
PDIP
TABLE 2: P
IN
D
ESCRIPTION
Symbol
A
17
-A
7
A
6
-A
0
Pin Name
Row Address Inputs
Column Address Inputs
Data Input/output
Functions
To provide memory addresses. Row addresses define a page for a Write cycle.
Column Addresses are toggled to load page data
To output data during Read cycles and receive input data during Write cycles.
Data is internally latched during a Write cycle.
The outputs are in tri-state when OE# or CE# is high.
To activate the device when CE# is low.
To gate the data output buffers.
To control the Write operations.
To provide:
5.0V supply (±10%) for SST29EE020
3.0V supply (3.0-3.6V) for SST29LE020
2.7V supply (2.7-3.6V) for SST29VE020
DQ
7
-DQ
0
CE#
OE#
WE#
V
DD
Chip Enable
Output Enable
Write Enable
Power Supply
V
SS
NC
Ground
No Connection
Unconnected pins.
T2.2 307
©2001 Silicon Storage Technology, Inc.
S71062-06-000 6/01
307
5
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