STK14D88
32Kx8 AutoStore™ nvSRAM
Features
Description
■ 25, 35, 45 ns Read Access and R/W Cycle Time
■ Unlimited Read/Write Endurance
The Cypress STK14D88 is a 256Kb fast static RAM with a
nonvolatile Quantum Trap™ storage element included with each
memory cell.
■ Automatic Nonvolatile STORE on Power Loss
■ Nonvolatile STORE Under Hardware or Software Control
■ Automatic RECALL to SRAM on Power Up
■ Unlimited RECALL Cycles
The SRAM provides fast access and cycle times, ease of use,
and unlimited read and write endurance of a normal SRAM.
Data transfers automatically to the nonvolatile storage cells
when power loss is detected (the STORE operation). On power
up, data is automatically restored to the SRAM (the RECALL
operation). Both STORE and RECALL operations are also
available under software control.
■ 200K STORE Cycles
■ 20-Year Nonvolatile Data Retention
The Cypress nvSRAM is the first monolithic nonvolatile memory
to offer unlimited writes and reads. It is the highest performance,
most reliable nonvolatile memory available.
■ Single 3.0V +20%, -10% Power Supply
■ Commercial, Industrial Temperatures
■ Small Footprint SOIC and SSOP Packages (RoHS-Compliant)
Logic Block Diagram
V
V
CAP
CCX
Quantum Trap
512 x 512
POWER
CONTROL
A
A
A
A
A
A
A
A
A
5
STORE
6
7
STORE/
RECALL
CONTROL
STATIC RAM
ARRAY
512 x 512
8
HSB
RECALL
9
11
12
13
14
SOFTWARE
DETECT
A - A
0
13
DQ
DQ
DQ
0
1
2
COLUMN I/O
COLUMN DEC
DQ
DQ
3
4
DQ
DQ
DQ
5
6
7
A A A A A A
10
0
1
2
3
4
G
E
W
Cypress Semiconductor Corporation
Document Number: 001-52037 Rev. **
•
198 Champion Court
•
San Jose, CA 95134-1709
•
408-943-2600
Revised March 02, 2009
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STK14D88
Absolute Maximum Ratings
Voltage on Input Relative to Ground.................–0.5V to 4.1V
Note: Stresses greater than those listed under “Absolute
Maximum Ratings” may cause permanent damage to the device.
This is a stress rating only, and functional operation of the device
at conditions above those indicated in the operational sections
of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
reliability.
Voltage on Input Relative to VSS...........–0.6V to (V + 0.5V)
CC
Voltage on DQ0-7 or HSB......................–0.5V to (V + 0.5V)
CC
Temperature under Bias ............................... –55°C to 125°C
Storage Temperature.................................... –65°C to 140°C
Power Dissipation............................................................. 1W
DC Output Current (1 output at a time, 1s duration)..... 15mA
NF (SOP-32) PACKAGE THERMAL CHARACTERISTICS
θ 5.4 C/W; θ 44.3 [0fpm], 37.9 [200fpm], 35.1 C/W [500fpm].
jc
ja
RF (SSOP-48) PACKAGE THERMAL CHARACTERISTICS
θ 6.2 C/W; θ 51.1 [0fpm], 44.7 [200fpm], 41.8 C/W [500fpm].
jc
ja
DC Characteristics
(V = 2.7V-3.6V)
CC
Commercial
Min Max
Industrial
Symbol
Parameter
Average V Current
Unit
Notes
Min
Max
I
65
55
50
70
60
55
mA
mA
mA
t
t
t
= 25ns
= 35ns
= 45ns
CC
CC
AVAV
AVAV
AVAV
1
Dependent on output loading and
cycle rate. Values obtained without
output loads.
I
I
Average V Current during
STORE
3
3
mA All Inputs Don’t Care, V = max
CC
CC
CC
2
3
Average current for duration of
STORE cycle (t
)
STORE
Average V Current at t
=
10
10
mA W ≥ (V – 0.2V)
CC
CC
CC
AVAV
200ns
3V, 25°C, Typical
All Others Cycling, CMOS Levels
Dependent on output loading and
cycle rate. Values obtained without
output loads.
I
I
Average V
AutoStore Cycle
Current during
3
3
3
3
mA All Inputs Don’t Care
CC
CAP
4
Average current for duration of
STORE cycle (t
)
STORE
V
Standby Current
mA E ≥ (V – 0.2V)
CC
SB
CC
(Standby, Stable CMOS Input
Levels)
All Others V ≤ 0.2V or ≥ (V
–
IN
CC
0.2V)
Standby current level after nonvol-
atile cycle complete
I
I
Input Leakage Current
±1
±1
±1
±1
μA
μA
V
= max
CC
ILK
V
= V to V
IN
SS
CC
Off-State Output Leakage Current
V = max
CC
OLK
V
= V to V , E or G ≥ V
IN
SS
CC
IH
V
V
V
Input Logic “1” Voltage
Input Logic “0” Voltage
Output Logic “1” Voltage
2.0
– .5
V
+ .5
2.0
V + .5
CC
V
V
V
All Inputs
All Inputs
IH
CC
V
0.8
V – .5
SS
0.8
IL
SS
2.4
2.4
I
=– 2mA
OUT
OH
Note:
2. The HSB pin has I
=-10uA for V of 2.4V, this parameter is characterized but not tested
OH
OUT
Document Number: 001-52037 Rev. **
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STK14D88
DC Characteristics (continued)
(V = 2.7V-3.6V)
CC
Commercial
Min Max
Industrial
[2]
Symbol
Parameter
Unit
Notes
Min
Max
V
T
Output Logic “0” Voltage
Operating Temperature
Operating Voltage
0.4
70
0.4
85
V
°C
V
I
= 4mA
OUT
OL
0
-40
2.7
17
A
V
2.7
17
3.6
120
3.6
120
3.3V +20%, -10%
CC
V
Storage Capacitance
μF Between V
pin and V , 5V
CAP
CAP SS
Rated
DATA
Data Retention
20
20
K
R
NV
Nonvolatile STORE Operations
200
200
Years @ 55°C
C
AC Test Conditions
Input Pulse Levels....................................................0V to 3V
Input Rise and Fall Times ............................................ <5 ns
Input and Output Timing Reference Levels.................... 1.5V
Figure 2. AC Output Loading
3.0V
577Ω
OUTPUT
30 pF
789Ω
INCLUDING
SCOPE AND
FIXTURE
Figure 3. AC Output Loading for Tri-state Specs (t , t , t
, t
, t
, t
HZ LZ WLQZ WHQZ GLQX GHQZ
3.0V
577
Ω
OUTPUT
5 pF
789
Ω
INCLUDING
SCOPE AND
FIXTURE
Capacitance
[3]
Parameter
Description
Input Capacitance
Output Capacitance
Test Conditions
T = 25°C, f = 1 MHz,
Max
7
Unit
pF
Conditions
ΔV = 0 to 3V
ΔV = 0 to 3V
C
IN
A
C
7
pF
OUT
Note
3. These parameters are guaranteed but not tested.
Document Number: 001-52037 Rev. **
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STK14D88
SRAM READ Cycles #1 and #2
Symbols
NO.
STK14D88-25 STK14D88-35 STK14D88-45
Parameter
Unit
#1
#2
Alt.
Min
Max
Min
Max
Min
Max
1
2
3
4
5
6
t
t
t
t
t
t
t
Chip Enable Access Time
Read Cycle Time
25
35
45
ns
ns
ns
ns
ns
ns
ELQV
ACS
t
t
t
25
35
45
AVAV
ELEH
[5]
AVQV
RC
AA
OE
OH
LZ
t
Address Access Time
25
12
35
15
45
20
AVQV
t
t
t
Output Enable to Data Valid
Output Hold after Address Change
GLQV
AXQX
ELQX
[5]
[6]
t
3
3
3
3
3
3
AXQX
Address Change or Chip Enable to
Output Active
7
t
t
Address Change or Chip Disable to
Output Inactive
10
13
15
ns
EHQZ
HZ
8
9
t
t
t
t
t
t
t
t
Output Enable to Output Active
Output Disable to Output Inactive
Chip Enable to Power Active
Chip Disable to Power Standby
0
0
0
0
0
0
ns
ns
ns
ns
GLQX
OLZ
OHZ
PA
10
25
13
35
15
45
GHQZ
10
11
ELICCH
EHICCL
PS
AVAV
t
ADDRESS
AVQV
t
AXQX
t
DQ (DATA OUT)
DATA VALID
Notes
4. W must be high during SRAM READ cycles.
5. Device is continuously selected with E and G both low.
6. Measured ± 200mV from steady state output voltage.
7. HSB must remain high during READ and WRITE cycles.
Document Number: 001-52037 Rev. **
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STK14D88
SRAM WRITE Cycle #1 and #2
Symbols
NO.
STK14D88-25 STK14D88-35 STK14D88-45
Parameter
Write Cycle Time
Unit
#1
#2
Alt.
Min
25
20
20
10
0
Max
Min
35
25
25
12
0
Max
Min
45
30
30
15
0
Max
12
13
14
15
16
17
18
19
20
21
t
t
t
WC
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
AVAV
AVAV
t
t
t
Write Pulse Width
WLWH
WLEH
WP
CW
DW
t
t
t
t
Chip Enable to End of Write
Data Set-up to End of Write
Data Hold after End of Write
Address Set-up to End of Write
Address Set-up to Start of Write
Address Hold after End of Write
Write Enable to Output Disable
Output Active after End of Write
ELWH
DVWH
WHDX
ELEH
DVEH
EHDX
t
t
t
t
t
DH
AW
t
t
t
20
0
25
0
30
0
AVWH
AVEH
t
t
t
AS
AVWL
AVEL
t
t
t
0
0
0
WHAX
WLQZ
EHAX
WR
t
t
10
13
15
WZ
t
t
3
3
3
WHQX
OW
Figure 6. SRAM WRITE Cycle 1: W Controlled
AVAV
t
ADDRESS
WHAX
ELWH
t
t
E
AVWH
t
AVWL
t
WLWH
t
W
DVWH
WHDX
t
t
DATA IN
DATA VALID
WLQZ
t
WHQX
t
HIGH IMPEDANCE
DATA OUT
PREVIOUS DATA
Figure 7. SRAM WRITE Cycle 2: E Controlled
AVAV
t
ADDRESS
E
AVEL
ELEH
EHAX
t
t
AVEH
t
WLEH
t
W
DVEH
EHDX
t
t
DATA IN
DATA VALID
HIGH IMPEDANCE
DATA OUT
Notes
8. If W is low when E goes low, the outputs remain in the high-impedance state.
9. E or W must be ≥ V during address transitions.
IH
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STK14D88
AutoStore/POWER UP RECALL
STK14D88
No. Symbols
Alt.
Parameter
Unit
Notes
Min
Max
20
22
23
24
25
t
t
Power up RECALL Duration
STORE Cycle Duration
Low Voltage Trigger Level
Vcc Rise Time
ms
ms
V
RECALL
STORE
t
12.5
2.65
HLHZ
V
V
SWITCH
CCRISE
150
μs
Figure 8. AutoStore /POWER UP RECALL
Note: Read and Write cycles are ignored during STORE, RECALL, and while V is below V
CC
SWITCH
Notes
10. t
starts from the time V rises above V
.
SWITCH
HRECALL
CC
11. If an SRAM WRITE has not taken place since the last nonvolatile cycle, no STORE will take place.
12. Industrial Grade Devices require 15 ms Max.
Document Number: 001-52037 Rev. **
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STK14D88
Software-Controlled STORE/RECALL Cycle
Symbols
No.
STK14D88-25 STK14D88-35 STK14D88-45
Parameter
Alternate
Unit Notes
E Cont
Min
Max
Min
Max
Min
Max
26 t
t
t
STORE/RECALL Initiation Cycle Time
25
0
35
0
45
0
ns
ns
AVAV
RC
27
28
29
30
Address Setup Time
Clock Pulse Width
Address Hold Time
RECALL Duration
t
t
t
t
AS
AVEL
t
20
1
25
1
30
1
ns
ns
μs
CW
ELEH
EHAX
RECALL
50
50
50
Figure 9. E and G Controlled Software STORE/RECALL Cycle
AVAV
t
AVAV
t
ADDRESS #1
ADDRESS #6
ADDRESS
AVEL
t
ELEH
t
E
ELAX
t
RECALL
tSTORE / t
HIGH IMPEDANCE
DATA VALID
DATA VALID
DQ (DATA
Notes
13. The software sequence is clocked on the falling edge of E controlled READs.
14. The six consecutive addresses must be read in the order listed in the software STORE/RECALL Mode Selection Table. W must be high during all six consecutive cycles.
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STK14D88
Hardware STORE Cycle
Symbols
NO.
STK14D88
Parameter
Unit
Notes
Standard Alternate
Min
Max
31
32
t
t
t
Hardware STORE to SRAM Disabled
Hardware STORE Pulse Width
1
70
µs
ns
DELAY
HLHX
HLQZ
15
Figure 10. Hardware STORE Cycle
Soft Sequence Commands
Symbols
STK14D88
NO.
Parameter
Min
Unit
µs
Notes
Standard
Max
33
t
Soft Sequence Processing Time
70
SS
Figure 11. Software Sequence Commands
Notes
15. Read and Write cycles in progress before HSB is asserted are given this minimum amount of time to complete.
16. This is the amount of time that it takes to take action on a soft sequence command. Vcc power must remain high to effectively register command.
17. Commands like Store and Recall lock out I/O until operation is complete which further increases this time. See specific command.
Document Number: 001-52037 Rev. **
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STK14D88
Notes
Mode Selection
E
H
L
W
X
H
L
G
X
L
A
–A
Mode
IO
Power
Standby
Active
14
0
X
Not Selected
Read SRAM
Write SRAM
Output High Z
Output Data
Input Data
X
X
L
X
L
Active
L
H
0x0E38
0x31C7
0x03E0
0x3C1F
0x303F
0x03F8
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Output Data
Output Data
Output Data
Output Data
Output Data
Output Data
Active
AutoStore Disable
L
L
H
H
L
L
0x0E38
0x31C7
0x03E0
0x3C1F
0x303F
0x07F0
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Output Data
Output Data
Output Data
Output Data
Output Data
Output Data
Active
AutoStore Enable
0x0E38
0x31C7
0x03E0
0x3C1F
0x303F
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Output Data
Output Data
Output Data
Output Data
Output Data
Active
0x0FC0
Nonvolatile Store
Output High Z
I
CC2
L
H
L
0x0E38
0x31C7
0x03E0
0x3C1F
0x303F
0x0C63
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Output Data
Output Data
Output Data
Output Data
Output Data
Output High Z
Active
Nonvolatile Recall
Notes
18. The six consecutive addresses must be in the order listed. W must be high during all six consecutive cycles to enable a nonvolatile cycle.
19. While there are 15 addresses on the STK14D88, only the lower 14 are used to control software modes
20. I/O state depends on the state of G. The I/O table shown assumes G low.
Document Number: 001-52037 Rev. **
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STK14D88
V
pin is driven to 5V by a charge pump internal to the chip. A
nvSRAM Operation
CAP
pull up should be placed on W to hold it inactive during power up.
nvSRAM
To reduce unneeded nonvolatile stores, AutoStore and
Hardware Store operations will be ignored unless at least one
WRITE operation has taken place since the most recent STORE
or RECALL cycle. Software initiated STORE cycles are
performed regardless of whether a WRITE operation has taken
place. The HSB signal can be monitored by the system to detect
an AutoStore cycle is in progress.
The STK14D88 nvSRAM is made up of two functional compo-
nents paired in the same physical cell. These are the SRAM
memory cell and a nonvolatile QuantumTrap™ cell. The SRAM
memory cell operates like a standard fast static RAM. Data in the
SRAM can be transferred to the nonvolatile cell (the STORE
operation), or from the nonvolatile cell to SRAM (the RECALL
operation). This unique architecture allows all cells to be stored
and recalled in parallel. During the STORE and RECALL opera-
tions SRAM READ and WRITE operations are inhibited. The
STK14D88 supports unlimited read and writes like a typical
SRAM. In addition, it provides unlimited RECALL operations
from the nonvolatile cells and up to 200K STORE operations.
Figure 12. AutoStore Mode
VCC
VCAP
VCC
SRAM READ
W
The STK14D88 performs a READ cycle whenever E and G are
low while W and HSB are high. The address specified on pins
A
determine which of the 32,768 data bytes will be accessed.
0-16
When the READ is initiated by an address transition, the outputs
will be valid after a delay of t (READ cycle #1). If the READ
AVQV
is initiated by E and G, the outputs will be valid at t
or at
ELQV
t
, whichever is later (READ cycle #2). The data outputs will
GLQV
repeatedly respond to address changes within the t
access
AVQV
time without the need for transitions on any control input pins,
and will remain valid until another address change or until either
E or G is brought high, or W or HSB is brought low.
Hardware STORE (HSB) Operation
SRAM WRITE
The STK14D88 provides the HSB pin for controlling and
acknowledging the STORE operations. The HSB pin can be
used to request a hardware STORE cycle. When the HSB pin is
driven low, the STK14D88 will conditionally initiate a STORE
A WRITE cycle is performed whenever E and W are low and HSB
is high. The address inputs must be stable prior to entering the
WRITE cycle and must remain stable until either E or W goes
high at the end of the cycle. The data on the common I/O pins
operation after t
. An actual STORE cycle will only begin if
DELAY
DQ will be written into memory if it is valid t
before the
0-7
DVWH
a WRITE to the SRAM took place since the last STORE or
RECALL cycle. The HSB pin has a very resistive pull up and is
internally driven low to indicate a busy condition while the
STORE (initiated by any means) is in progress. This pin should
be externally pulled up if it is used to drive other inputs.
end of a W controlled WRITE or t
controlled WRITE.
before the end of an E
DVEH
It is recommended that G be kept high during the entire WRITE
cycle to avoid data bus contention on common I/O lines. If G is
left low, internal circuitry will turn off the output buffers t
after
WLQZ
SRAM READ and WRITE operations that are in progress when
HSB is driven low by any means are given time to complete
before the STORE operation is initiated. After HSB goes low, the
goes low.
W
AutoStore Operation
STK14D88 will continue SRAM operations for t
. During
DELAY
The STK14D88 stores data to nvSRAM using one of three
storage operations. These three operations are Hardware Store
(activated by HSB), Software Store (activated by an address
sequence), and AutoStore (on power down).
t
, multiple SRAM READ operations may take place. If a
DELAY
WRITE is in progress when HSB is pulled low, it will be allowed
a time, t , to complete. However, any SRAM WRITE cycles
DELAY
requested after HSB goes low will be inhibited until HSB returns
high.
AutoStore operation is a unique feature of Cypress Quantum
Trap technology is enabled by default on the STK14D88.
If HSB is not used, it should be left unconnected.
CC
Software STORE
charge will be used by the chip to perform a single STORE
operation. If the voltage on the V pin drops below VSWITCH,
Data can be transferred from the SRAM to the nonvolatile
memory by a software address sequence. The STK14D88
software STORE cycle is initiated by executing sequential E
controlled READ cycles from six specific address locations in
exact order. During the STORE cycle, previous data is erased
and then the new data is programmed into the nonvolatile
elements. Once a STORE cycle is initiated, further memory
inputs and outputs are disabled until the cycle is completed.
CC
the part will automatically disconnect the V
pin from V . A
CAP
CC
STORE operation will be initiated with power provided by the
capacitor.
V
CAP
Figure 12 shows the proper connection of the storage capacitor
(V ) for automatic store operation. Refer to the DC CHARAC-
CAP
TERISTICS table for the size of the capacitor. The voltage on the
Document Number: 001-52037 Rev. **
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STK14D88
To initiate the software STORE cycle, the following READ
sequence must be performed:
■ The nonvolatile cells in an nvSRAM are programmed on the
test floor during final test and quality assurance. Incoming
inspection routines at customer or contract manufacturer’s
sites willsometimes reprogram these values. Final NV patterns
are typically repeating patterns of AA, 55, 00, FF, A5, or 5A.
End product’s firmware should not assume an NV array is in a
set programmed state. Routines that check memory content
values to determine first time system configuration, cold or
warm boot status, etc. should always program a unique NV
pattern (e.g., complex 4-byte pattern of 46 E6 49 53 hex or
more random bytes) as part of the final system manufacturing
test to ensure these system routines work consistently.
1. Read Address 0x0E38, Valid READ
2. Read Address 0x31C7, Valid READ
3. Read Address 0x03E0, Valid READ
4. Read Address 0x3C1F, Valid READ
5. Read Address 0x303F, Valid READ
6. Read Address 0x0FC0, Initiate STORE Cycle
Once the sixth address in the sequence has been entered, the
STORE cycle will commence and the chip will be disabled. It is
important that READ cycles and not WRITE cycles be used in
■ Power up boot firmware routines should rewrite the nvSRAM
into the desired state (autostore enabled, etc.). While the
nvSRAM is shipped in a preset state, best practice is to again
rewrite the nvSRAM into the desired state as a safeguard
against events that might flip the bit inadvertently (program
bugs, incoming inspection routines, etc.).
the sequence. After the t
cycle time has been fulfilled, the
STORE
SRAM will again be activated for READ and WRITE operation.
Software RECALL
Data can be transferred from the nonvolatile memory to the
SRAM by a software address sequence. A software RECALL
cycle is initiated with a sequence of READ operations in a
manner similar to the software STORE initiation. To initiate the
RECALL cycle, the following sequence of E controlled READ
operations must be performed:
■ If AutoStore has been firmware disabled, it will not reset to
“autostore enabled” on every power down event captured by
the nvSRAM. The application firmware should re-enable or
re-disable autostore on each reset sequence based on the
behavior desired.
1. Read Address 0x0E38, Valid READ
2. Read Address 0x31C7, Valid READ
3. Read Address 0x03E0, Valid READ
4. Read Address 0x3C1F, Valid READ
5. Read Address 0x303F, Valid READ
6. Read Address 0x0C63, Initiate RECALL Cycle
■ TheV
valuespecifiedinthisdatasheetincludesaminimum
CAP
and a maximum value size. Best practice is to meet this
requirement and not exceed the max V
nvSRAM internal algorithm calculates V
value because the
charge time based
CAP
CAP
on this max V
value. Customers that want to use a larger
CAP
V
value to make sure there is extra store charge and store
CAP
time should discuss their V
size selection with Cypress to
CAP
Internally, RECALL is a two-step procedure. First, the SRAM
data is cleared, and second, the nonvolatile information is trans-
understand any impact on the V
voltage level at the end of
CAP
a t
period.
RECALL
ferred into the SRAM cells. After the t
cycle time, the
RECALL
Low Average Active Power
SRAM will once again be ready for READ or WRITE operations.
The RECALL operation in no way alters the data in the nonvol-
atile storage elements.
CMOS technology provides the STK14D88 with the benefit of
power supply current that scales with cycle time. Less current will
be drawn as the memory cycle time becomes longer than 50 ns.
Data Protection
I
and
CC
The STK14D88 protects data from corruption during low-voltage
conditions by inhibiting all externally initiated STORE and
WRITE operations. The low-voltage condition is detected when
READ/WRITE cycle time. Worst-case current consumption is
shown for commercial temperature range, V = 3.6V, and chip
CC
enable at maximum frequency. Only standby current is drawn
when the chip is disabled. The overall average current drawn by
the STK14D88 depends on the following items:
V
<V
.
CC
SWITCH
If the STK14D88 is in a WRITE mode (both E and W low) at
power-up, after a RECALL, or after a STORE, the WRITE will be
inhibited until a negative transition on E or W is detected. This
protects against inadvertent writes during power up or brown out
conditions.
■ The duty cycle of chip enable
■ The overall cycle rate for operations
■ The ratio of READs to WRITEs
■ The operating temperature
Best Practices
nvSRAM products have been used effectively for over 15 years.
While ease-of-use is one of the product’s main system values,
experience gained working with hundreds of applications has
resulted in the following suggestions as best practices:
■ The V level
CC
■ I/O loading
Document Number: 001-52037 Rev. **
Page 12 of 17
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STK14D88
Figure 13. Current versus Cycle Time
Preventing AutoStore
The AutoStore function can be disabled by initiating an
AutoStore Disable sequence. A sequence of READ operations
is performed in a manner similar to the software STORE initi-
ation. To initiate the AutoStore Disable sequence, the following
sequence of E controlled or G controlled READ operations must
be performed:
50
40
30
20
10
0
1. Read Address 0x0E38, Valid READ
2. Read Address 0x31C7, Valid READ
3. Read Address 0x03E0, Valid READ
4. Read Address 0x3C1F, Valid READ
5. Read Address 0x303F, Valid READ
6. Read Address 0x03F8, AutoStore Disable
Writes
Reads
The AutoStore can be re-enabled by initiating an AutoStore
Enable sequence. A sequence of READ operations is performed
in a manner similar to the software RECALL initiation. To initiate
the AutoStore Enable sequence, the following sequence of E
controlled or G controlled READ operations must be performed:
50 100 150 200 300
Cycle Time (ns)
1. Read Address 0x0E38, Valid READ
2. Read Address 0x31C7, Valid READ
3. Read Address 0x03E0, Valid READ
4. Read Address 0x3C1F, Valid READ
5. Read Address 0x303F, Valid READ
6. Read Address 0x07F0, AutoStore Enable
Noise Considerations
The STK14D88 is a high-speed memory and so must have a
high-frequency bypass capacitor of 0.1 µF connected between
both V pins and V ground plane with no plane break to chip
CC
SS
V
. Use leads and traces that are as short as possible. As with
SS
all high-speed CMOS ICs, careful routing of power, ground, and
signals will reduce circuit noise.
If the AutoStore function is disabled or re-enabled, a manual
STORE operation (Hardware or Software) needs to be issued to
save the AutoStore state through subsequent power down
cycles. The part comes from the factory with AutoStore enabled.
In all cases, make sure the READ sequence is uninterrupted. For
example, an interrupt that occurs in the sequence that reads the
nvSRAM would abort this sequence, resulting in an error.
Document Number: 001-52037 Rev. **
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STK14D88
Part Numbering Nomenclature
STK14D88 - R F 45 I TR
Packaging Option:
TR = Tape and Reel
Blank = Tube
Temperature Range:
Blank - Commercial (0 to 70°C)
I - Industrial (-40 to 85°C)
Speed:
25 - 25 ns
35 - 35 ns
45 - 45 ns
Lead Finish
F = 100% Sn (Matte Tin) ROHS Compliant
Package:
N = Plastic 32-pin 300 mil SOIC (50 mil pitch)
R = Plastic 48-pin 300 mil SSOP(25 mil pitch)
Ordering Codes
Part Number
Description
Access Times Temperature
STK14D88-NF25
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SOP32-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
3V 32Kx8 AutoStore nvSRAM SSOP48-300
25 ns
35 ns
45 ns
25 ns
35 ns
45 ns
25 ns
35 ns
45 ns
25 ns
35 ns
45 ns
25 ns
35 ns
45 ns
25 ns
35 ns
45 ns
25 ns
35 ns
45 ns
25 ns
35 ns
45 ns
Commercial
Commercial
Commercial
Commercial
Commercial
Commercial
Commercial
Commercial
Commercial
Commercial
Commercial
Commercial
Industrial
STK14D88-NF35
STK14D88-NF45
STK14D88-NF25TR
STK14D88-NF35TR
STK14D88-NF45TR
STK14D88-RF25
STK14D88-RF35
STK14D88-RF45
STK14D88-RF25TR
STK14D88-RF35TR
STK14D88-RF45TR
STK14D88-NF25I
STK14D88-NF35I
STK14D88-NF45I
STK14D88-NF25ITR
STK14D88-NF35ITR
STK14D88-NF45ITR
STK14D88-RF25I
STK14D88-RF35I
STK14D88-RF45I
STK14D88-RF25ITR
STK14D88-RF35ITR
STK14D88-RF45ITR
Industrial
Industrial
Industrial
Industrial
Industrial
Industrial
Industrial
Industrial
Industrial
Industrial
Industrial
Document Number: 001-52037 Rev. **
Page 14 of 17
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STK14D88
Package Diagrams
Figure 14. 32-Pin (300 Mil) SOIC (51-85127)
PIN 1 ID
16
1
MIN.
MAX.
DIMENSIONS IN INCHES[MM]
REFERENCE JEDEC MO-119
0.292[7.416]
0.299[7.594]
0.405[10.287]
0.419[10.642]
PART #
17
32
S32.3 STANDARD PKG.
SZ32.3 LEAD FREE PKG.
SEATING PLANE
0.810[20.574]
0.822[20.878]
0.090[2.286]
0.100[2.540]
0.004[0.101]
0.050[1.270]
TYP.
0.006[0.152]
0.012[0.304]
0.026[0.660]
0.032[0.812]
0.021[0.533]
0.041[1.041]
0.004[0.101]
0.0100[0.254]
0.014[0.355]
0.020[0.508]
51-85127 *A
Document Number: 001-52037 Rev. **
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STK14D88
Package Diagrams (continued)
Figure 15. 48-Pin (300 Mil) SSOP (51-85061)
51-85061-*C
Document Number: 001-52037 Rev. **
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STK14D88
Document History Page
Document Title: STK14D88 32Kx8 AutoStore™ nvSRAM
Document Number: 001-52037
Orig. of Submission
Revision
ECN
Description of Change
Change
Date
**
2668632
GVCH
03/04/2009 New data sheet
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© Cypress Semiconductor Corporation, 2009. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use of any
circuitry other than circuitry embodied in a Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor intended to be used for medical,
life support, life saving, critical control or safety applications, unless pursuant to an express written agreement with Cypress. Furthermore, Cypress does not authorize its products for use as critical
components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress products in life-support systems
application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges.
Any Source Code (software and/or firmware) is owned by Cypress Semiconductor Corporation (Cypress) and is protected by and subject to worldwide patent protection (United States and foreign),
United States copyright laws and international treaty provisions. Cypress hereby grants to licensee a personal, non-exclusive, non-transferable license to copy, use, modify, create derivative works of,
and compile the Cypress Source Code and derivative works for the sole purpose of creating custom software and or firmware in support of licensee product to be used only in conjunction with a Cypress
integrated circuit as specified in the applicable agreement. Any reproduction, modification, translation, compilation, or representation of this Source Code except as specified above is prohibited without
the express written permission of Cypress.
Disclaimer: CYPRESS MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Cypress reserves the right to make changes without further notice to the materials described herein. Cypress does not
assume any liability arising out of the application or use of any product or circuit described herein. Cypress does not authorize its products for use as critical components in life-support systems where
a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress’ product in a life-support systems application implies that the manufacturer
assumes all risk of such use and in doing so indemnifies Cypress against all charges.
Use may be limited by and subject to the applicable Cypress software license agreement.
Document Number: 001-52037 Rev. **
Revised March 02, 2009
Page 17 of 17
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holders.
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