Cypress CY7C1231F 2-mbit (128k x 18) flow-through sram with noblâ ¢ architecture Datasheet

CY7C1231F
2-Mbit (128K x 18) Flow-through SRAM with
NoBL™ Architecture
Functional Description[1]
Features
• Can support up to 117-MHz bus operations with zero
wait states
— Data is transferred on every clock
• Pin compatible and functionally equivalent to ZBT™
devices
• Internally self-timed output buffer control to eliminate
the need to use OE
• Registered inputs for flow-through operation
The CY7C1231F is a 3.3V, 128K x 18 Synchronous
Flow-through Burst SRAM designed specifically to support
unlimited true back-to-back Read/Write operations without the
insertion of wait states. The CY7C1231F is equipped with the
advanced No Bus Latency™ (NoBL™) logic required to
enable consecutive Read/Write operations with data being
transferred on every clock cycle. This feature dramatically
improves the throughput of data through the SRAM, especially
in systems that require frequent Write-Read transitions.
All synchronous inputs pass through input registers controlled
by the rising edge of the clock. The clock input is qualified by
the Clock Enable (CEN) signal, which when deasserted
suspends operation and extends the previous clock cycle.
Maximum access delay from the clock rise is 7.5 ns (117-MHz
device).
• Byte Write capability
• 128K x 18 common I/O architecture
• Single 3.3V power supply
• Fast clock-to-output times
— 7.5 ns (for 117-MHz device)
Write operations are controlled by the two Byte Write Select
(BW[A:B]) and a Write Enable (WE) input. All writes are
conducted with on-chip synchronous self-timed write circuitry.
— 8.5 ns (for 100-MHz device)
• Clock Enable (CEN) pin to suspend operation
Three synchronous Chip Enables (CE1, CE2, CE3) and an
asynchronous Output Enable (OE) provide for easy bank
selection and output three-state control. In order to avoid bus
contention, the output drivers are synchronously three-stated
during the data portion of a write sequence.
• Synchronous self-timed writes
• Asynchronous Output Enable
• JEDEC-standard 100 TQFP package
• Burst Capability—linear or interleaved burst order
• Low standby power
Logic Block Diagram
ADDRESS
REGISTER
A0, A1, A
A1
D1
A0
D0
MODE
CLK
CEN
C
CE
ADV/LD
C
BURST
LOGIC
Q1 A1'
A0'
Q0
WRITE ADDRESS
REGISTER
ADV/LD
BWA
WRITE REGISTRY
AND DATA COHERENCY
CONTROL LOGIC
BWB
WRITE
DRIVERS
MEMORY
ARRAY
S
E
N
S
E
A
M
P
S
WE
OE
CE1
CE2
CE3
ZZ
INPUT
REGISTER
D
A
T
A
S
T
E
E
R
I
N
G
O
U
T
P
U
T
B
U
F
F
E
R
S
DQs
DQPA
DQPB
E
E
READ LOGIC
SLEEP
CONTROL
Note:
1. For best-practices recommendations, please refer to the Cypress application note System Design Guidelines on www.cypress.com.
Cypress Semiconductor Corporation
Document #: 38-05437 Rev. *C
•
3901 North First Street
•
San Jose, CA 95134
•
408-943-2600
Revised May 31, 2005
CY7C1231F
Selection Guide
CY7C1231F-117
CY7C1231F-100
Unit
Maximum Access Time
7.5
8.5
ns
Maximum Operating Current
220
205
mA
Maximum CMOS Standby Current
40
40
mA
Shaded areas contain advance information. Please contact your local Cypress sales representative for availability of this part.
Pin Configuration
Document #: 38-05437 Rev. *C
A
A
OE
86
81
CEN
87
82
WE
88
NC(9M)
CLK
89
83
VSS
90
ADV/LD
VDD
91
NC(18M)
CE3
92
84
BWA
93
85
NC
NC
96
BWB
CE2
97
94
A
CE1
98
A
99
95
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
51
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A
A
A
A1
A0
NC
NC
VSS
VDD
NC(72M)
NC(36M)
A
A
A
A
A
A
NC
CY7C1231F
A
BYTE B
VDDQ
VSS
NC
NC
DQB
DQB
VSS
VDDQ
DQB
DQB
NC
VDD
NC
VSS
DQB
DQB
VDDQ
VSS
DQB
DQB
DQPB
NC
VSS
VDDQ
NC
NC
NC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
MODE
NC
NC
NC
100
100-lead TQFP
A
NC
NC
VDDQ
VSS
NC
DQPA
DQA
DQA
VSS
VDDQ
DQA
DQA
VSS
NC
VDD
ZZ
BYTE A
DQA
DQA
VDDQ
VSS
DQA
DQA
NC
NC
VSS
VDDQ
NC
NC
NC
Page 2 of 12
CY7C1231F
Pin Definitions (100-pin TQFP Package)
Name
A0, A1, A
BW[A:B]
TQFP
I/O
Description
37,36,32,33,34,
InputAddress Inputs used to select one of the 128K address locations. Sampled
35,44,45,46,
Synchronous at the rising edge of the CLK. A[1:0] are fed to the two-bit burst counter.
47,48,49,80,81,
82,99,100
93,94
InputByte Write Inputs, active LOW. Qualified with WE to conduct writes to the
Synchronous SRAM. Sampled on the rising edge of CLK.
WE
88
InputWrite Enable Input, active LOW. Sampled on the rising edge of CLK if CEN is
Synchronous active LOW. This signal must be asserted LOW to initiate a write sequence.
ADV/LD
85
InputAdvance/Load Input. Used to advance the on-chip address counter or load a
Synchronous new address. When HIGH (and CEN is asserted LOW) the internal burst counter
is advanced. When LOW, a new address can be loaded into the device for an
access. After being deselected, ADV/LD should be driven LOW in order to load
a new address.
CLK
89
CE1
98
InputChip Enable 1 Input, active LOW. Sampled on the rising edge of CLK. Used in
Synchronous conjunction with CE2, and CE3 to select/deselect the device.
CE2
97
InputChip Enable 2 Input, active HIGH. Sampled on the rising edge of CLK. Used in
Synchronous conjunction with CE1 and CE3 to select/deselect the device.
CE3
92
InputChip Enable 3 Input, active LOW. Sampled on the rising edge of CLK. Used in
Synchronous conjunction with CE1 and CE2 to select/deselect the device.
OE
86
InputOutput Enable, asynchronous input, active LOW. Combined with the
Asynchronous synchronous logic block inside the device to control the direction of the I/O pins.
When LOW, the I/O pins are allowed to behave as outputs. When deasserted
HIGH, I/O pins are three-stated, and act as input data pins. OE is masked during
the data portion of a write sequence, during the first clock when emerging from
a deselected state, when the device has been deselected.
CEN
87
InputClock Enable Input, active LOW. When asserted LOW the Clock signal is recogSynchronous nized by the SRAM. When deasserted HIGH the Clock signal is masked. Since
deasserting CEN does not deselect the device, CEN can be used to extend the
previous cycle when required.
ZZ
64
InputZZ “sleep” Input. This active HIGH input places the device in a non-time critical
Asynchronous “sleep” condition with data integrity preserved. During normal operation, this pin
can be connected to VSS or left floating.
58,59,62,63,
68,69,72,73,8,
9,12,13,18,19,
22,23
I/OBidirectional Data I/O Lines. As inputs, they feed into an on-chip data register
Synchronous that is triggered by the rising edge of CLK. As outputs, they deliver the data
contained in the memory location specified by address during the clock rise of
the read cycle. The direction of the pins is controlled by OE and the internal control
logic. When OE is asserted LOW, the pins can behave as outputs. When HIGH,
DQs and DQP[A:B] are placed in a three-state condition. The outputs are automatically three-stated during the data portion of a write sequence, during the first
clock when emerging from a deselected state, and when the device is deselected,
regardless of the state of OE.
74,24
I/OBidirectional Data Parity I/O Lines. Functionally, these signals are identical to
Synchronous DQs. During write sequences, DQP[A:B] is controlled by BWx correspondingly.
DQs
DQP[A:B]
Mode
VDD
VDDQ
VSS
31
15,41,65,91
Input-Clock
Input
Strap Pin
Mode Input. Selects the burst order of the device. When tied to Gnd selects linear
burst sequence. When tied to VDD or left floating selects interleaved burst sequence.
Power Supply Power supply inputs to the core of the device.
4,11,20,27,54,
61,70,77
I/O Power
Supply
5,10,17,21,
26,40,55,60,
67,71,76,90
Ground
Document #: 38-05437 Rev. *C
Clock Input. Used to capture all synchronous inputs to the device. CLK is
qualified with CEN. CLK is only recognized if CEN is active LOW.
Power supply for the I/O circuitry.
Ground for the device.
Page 3 of 12
CY7C1231F
Pin Definitions (100-pin TQFP Package) (continued)
Name
NC
TQFP
I/O
1,2,3,6,7, 14,
16,25,28,29,30,
38,39,42,43,50,
51,52,53,56,57,
66,75,78,79,83,
84,95,96
–
Description
No Connects. Not Internally connected to the die.
9M, 18M, 36M, and 72M are address expansion pins and are not internally
connected to the die.
Functional Overview
The CY7C1231F is a synchronous flow-through burst SRAM
designed specifically to eliminate wait states during
Write-Read transitions. All synchronous inputs pass through
input registers controlled by the rising edge of the clock. The
clock signal is qualified with the Clock Enable input signal
(CEN). If CEN is HIGH, the clock signal is not recognized and
all internal states are maintained. All synchronous operations
are qualified with CEN. Maximum access delay from the clock
rise (tCDV) is 7.5 ns (117-MHz device).
Accesses can be initiated by asserting all three Chip Enables
(CE1, CE2, CE3) active at the rising edge of the clock. If Clock
Enable (CEN) is active LOW and ADV/LD is asserted LOW,
the address presented to the device will be latched. The
access can either be a read or write operation, depending on
the status of the Write Enable (WE). BW[A:B] can be used to
conduct Byte Write operations.
Write operations are qualified by the Write Enable (WE). All
writes are simplified with on-chip synchronous self-timed write
circuitry.
Three synchronous Chip Enables (CE1, CE2, CE3) and an
asynchronous Output Enable (OE) simplify depth expansion.
All operations (Reads, Writes, and Deselects) are pipelined.
ADV/LD should be driven LOW once the device has been
deselected in order to load a new address for the next
operation.
Single Read Accesses
A read access is initiated when the following conditions are
satisfied at clock rise: (1) CEN is asserted LOW, (2) CE1, CE2,
and CE3 are ALL asserted active, (3) the Write Enable input
signal WE is deasserted HIGH, and 4) ADV/LD is asserted
LOW. The address presented to the address inputs is latched
into the Address Register and presented to the memory array
and control logic. The control logic determines that a read
access is in progress and allows the requested data to
propagate to the output buffers. The data is available within 7.5
ns (117-MHz device) provided OE is active LOW. After the first
clock of the read access, the output buffers are controlled by
OE and the internal control logic. OE must be driven LOW in
order for the device to drive out the requested data. On the
subsequent clock, another operation (Read/Write/Deselect)
can be initiated. When the SRAM is deselected at clock rise
by one of the chip enable signals, its output will be three-stated
immediately.
Burst Read Accesses
The CY7C1231F has an on-chip burst counter that allows the
user the ability to supply a single address and conduct up to
four Reads without reasserting the address inputs. ADV/LD
must be driven LOW in order to load a new address into the
SRAM, as described in the Single Read Access section above.
Document #: 38-05437 Rev. *C
The sequence of the burst counter is determined by the MODE
input signal. A LOW input on MODE selects a linear burst
mode, a HIGH selects an interleaved burst sequence. Both
burst counters use A0 and A1 in the burst sequence, and will
wrap around when incremented sufficiently. A HIGH input on
ADV/LD will increment the internal burst counter regardless of
the state of Chip Enable inputs or WE. WE is latched at the
beginning of a burst cycle. Therefore, the type of access (Read
or Write) is maintained throughout the burst sequence.
Single Write Accesses
Write accesses are initiated when the following conditions are
satisfied at clock rise: (1) CEN is asserted LOW, (2) CE1, CE2,
and CE3 are ALL asserted active, and (3) the Write signal WE
is asserted LOW. The address presented to the address bus
is loaded into the Address Register. The write signals are
latched into the Control Logic block. The data lines are
automatically three-stated regardless of the state of the OE
input signal. This allows the external logic to present the data
on DQs and DQP[A:B].
On the next clock rise the data presented to DQs and DQP[A:B]
(or a subset for Byte Write operations, see Truth Table for
details) inputs is latched into the device and the write is
complete. Additional accesses (Read/Write/Deselect) can be
initiated on this cycle.
The data written during the Write operation is controlled by
BW[A:B] signals. The CY7C1231F provides Byte Write
capability that is described in the Truth Table. Asserting the
Write Enable input (WE) with the selected Byte Write Select
input will selectively write to only the desired bytes. Bytes not
selected during a Byte Write operation will remain unaltered.
A synchronous self-timed write mechanism has been provided
to simplify the Write operations. Byte Write capability has been
included in order to greatly simplify Read/Modify/Write
sequences, which can be reduced to simple byte write operations.
Because the CY7C1231F is a common I/O device, data should
not be driven into the device while the outputs are active. The
Output Enable (OE) can be deasserted HIGH before
presenting data to the DQs and DQP[A:B] inputs. Doing so will
three-state the output drivers. As a safety precaution, DQs and
DQP[A:B].are automatically three-stated during the data
portion of a write cycle, regardless of the state of OE.
Burst Write Accesses
The CY7C1231F has an on-chip burst counter that allows the
user the ability to supply a single address and conduct up to
four Write operations without reasserting the address inputs.
ADV/LD must be driven LOW in order to load the initial
address, as described in the Single Write Access section
above. When ADV/LD is driven HIGH on the subsequent clock
rise, the Chip Enables (CE1, CE2, and CE3) and WE inputs are
ignored and the burst counter is incremented. The correct
Page 4 of 12
CY7C1231F
BW[A:B] inputs must be driven in each cycle of the burst write,
in order to write the correct bytes of data.
Interleaved Burst Sequence
Sleep Mode
The ZZ input pin is an asynchronous input. Asserting ZZ
places the SRAM in a power conservation “sleep” mode. Two
clock cycles are required to enter into or exit from this “sleep”
mode. While in this mode, data integrity is guaranteed.
Accesses pending when entering the “sleep” mode are not
considered valid nor is the completion of the operation
guaranteed. The device must be deselected prior to entering
the “sleep” mode. CE1, CE2, and CE3, must remain inactive
for the duration of tZZREC after the ZZ input returns LOW.
First
Address
Second
Address
Third
Address
Fourth
Address
A1, A0
A1, A0
A1, A0
A1, A0
00
01
10
11
01
00
11
10
10
11
00
01
11
10
01
00
Linear Burst Address Table (MODE = GND)
First
Address
A1, A0
Second
Address
A1, A0
Third
Address
A1, A0
Fourth
Address
A1, A0
00
01
10
11
01
10
11
00
10
11
00
01
11
00
01
10
ZZ Mode Electrical Characteristics
Parameter
Description
Test Conditions
IDDZZ
Snooze mode standby current
ZZ > VDD − 0.2V
tZZS
Device operation to ZZ
ZZ > VDD − 0.2V
tZZREC
ZZ recovery time
ZZ < 0.2V
tZZI
ZZ Active to snooze current
This parameter is sampled
tRZZI
ZZ inactive to exit snooze current
This parameter is sampled
Document #: 38-05437 Rev. *C
Min.
Max.
Unit
40
mA
2tCYC
ns
2tCYC
ns
2tCYC
0
ns
ns
Page 5 of 12
CY7C1231F
Truth Table[2, 3, 4, 5, 6, 7, 8]
Address
Used CE1 CE2 CE3 ZZ ADV/LD WE BWX OE CEN CLK
None
H
X
X
L
L
X
X
X
L L->H
Operation
Deselect Cycle
Deselect Cycle
None
X
Deselect Cycle
None
Continue Deselect Cycle
None
READ Cycle (Begin Burst)
X
H
L
X
L
X
X
X
X
External
L
H
L
Next
X
X
X
External
L
H
L
Next
X
X
X
READ Cycle (Continue Burst)
NOP/DUMMY READ (Begin Burst)
DUMMY READ (Continue Burst)
WRITE Cycle (Begin Burst)
DQ
Three-State
L
X
X
X
L
L->H
Three-State
L
L
X
X
X
L
L->H
Three-State
L
H
X
X
X
L
L->H
Three-State
L
L
H
X
L
L
L->H Data Out (Q)
L
H
X
X
L
L
L->H Data Out (Q)
L
L
H
X
H
L
L->H
Three-State
L
H
X
X
H
L
L->H
Three-State
External
L
H
L
L
L
L
L
X
L
L->H
Data In (D)
WRITE Cycle (Continue Burst)
Next
X
X
X
L
H
X
L
X
L
L->H
Data In (D)
NOP/WRITE ABORT (Begin Burst)
None
L
H
L
L
L
L
H
X
L
L->H
Three-State
WRITE ABORT (Continue Burst)
Next
X
X
X
L
H
X
H
X
L
L->H
Three-State
IGNORE CLOCK EDGE (Stall)
Current
X
X
X
L
X
X
X
X
H
L->H
–
None
X
X
X
H
X
X
X
X
X
X
Three-State
SNOOZE MODE
Truth Table for Read/Write[2, 3]
Function
Read
Write – No bytes written
WE
H
BWA
X
BWB
X
L
H
H
Write Byte A – (DQA and DQPA)
L
H
H
Write Byte B – (DQB and DQPB)
L
H
H
Notes:
2. X = “Don't Care.” H = Logic HIGH, L = Logic LOW. BWx = 0 signifies at least one Byte Write Select is active, BWx = Valid signifies that the desired byte write
selects are asserted, see Truth Table for details.
3. Write is defined by BW[A:B], and WE. See Truth Table for Read/Write.
4. When a write cycle is detected, all I/Os are three-stated, even during byte writes.
5. The DQs and DQP[A:B] pins are controlled by the current cycle and the OE signal. OE is asynchronous and is not sampled with the clock.
6. CEN = H, inserts wait states.
7. Device will power-up deselected and the I/Os in a three-state condition, regardless of OE.
8. OE is asynchronous and is not sampled with the clock rise. It is masked internally during write cycles. During a read cycle DQs and DQP[A:B] = Three-state when
OE is inactive or when the device is deselected, and DQs and DQP[A:B] = data when OE is active.
Document #: 38-05437 Rev. *C
Page 6 of 12
CY7C1231F
Maximum Ratings
Current into Outputs (LOW)......................................... 20 mA
Static Discharge Voltage.......................................... > 2001V
(per MIL-STD-883, Method 3015)
(Above which the useful life may be impaired. For user guidelines, not tested.)
Latch-up Current.................................................... > 200 mA
Storage Temperature ................................. –65°C to +150°C
Operating Range
Ambient Temperature with
Power Applied............................................. –55°C to +125°C
Supply Voltage on VDD Relative to GND ...... –0.5V to +4.6V
Range
DC Voltage Applied to Outputs
in Three-State ..................................... –0.5V to VDDQ + 0.5V
Ambient
Temperature (TA)
Com’l
0°C to +70°C
VDD
VDDQ
3.3V –
5%/+10%
3.3V – 5% to
VDD
DC Input Voltage....................................–0.5V to VDD + 0.5V
Electrical Characteristics Over the Operating Range [9,10]
Parameter
Description
Test Conditions
Min.
Max.
Unit
VDD
Power Supply Voltage
for 3.3V I/O
3.135
3.6
V
VDDQ
I/O Supply Voltage
for 3.3V I/O
3.135
VDD
V
VOH
Output HIGH Voltage
for 3.3V I/O, IOH = –4.0 mA
VOL
Output LOW Voltage
for 3.3V I/O, IOL = 8.0 mA
VIH
Input HIGH Voltage
for 3.3V I/O
VIL
Input LOW Voltage[9]
for 3.3V I/O
IX
Input Load Current
(except ZZ and MODE)
GND ≤ VI ≤ VDDQ
−5
Input Current of MODE
Input = VSS
–30
2.4
V
2.0
VDD + 0.3V
V
–0.3
0.8
V
5
µA
Input = VDD
Input Current of ZZ
Output Leakage Current
GND ≤ VI ≤ VDD, Output Disabled
VDD Operating Supply
Current
VDD = Max., IOUT = 0 mA,
f = fMAX= 1/tCYC
ISB1
Automatic CE Power-down VDD = Max, Device Deselected,
Current—TTL Inputs
VIN ≥ VIH or VIN ≤ VIL, f = fMAX,
inputs switching
ISB2
Automatic CE Power-down VDD = Max, Device Deselected,
Current—CMOS Inputs
VIN ≥ VDD – 0.3V or VIN ≤ 0.3V,
f = 0, inputs static
ISB3
ISB4
µA
µA
–5
Input = VDD
IDD
µA
5
Input = VSS
IOZ
V
0.4
30
µA
5
µA
8.5-ns cycle, 117 MHz
220
mA
10-ns cycle, 100 MHz
205
mA
8.5-ns cycle, 117 MHz
85
mA
10-ns cycle, 100 MHz
80
mA
All speeds
40
mA
Automatic CE Power-down VDD = Max, Device Deselected, 8.5-ns cycle, 117 MHz
Current—CMOS Inputs
VIN ≥ VDDQ – 0.3V or VIN ≤ 0.3V, 10-ns cycle, 100 MHz
f = fMAX, inputs switching
70
mA
65
mA
Automatic CE Power-down VDD = Max, Device Deselected,
Current—TTL Inputs
VIN ≥ VDD – 0.3V or VIN ≤ 0.3V,
f = 0, inputs static
45
mA
–5
All speeds
Shaded areas contain advance information. Please contact your local Cypress sales representative for availability of this part.
Notes:
9. Overshoot: VIH(AC) < VDD +1.5V (Pulse width less than tCYC/2), undershoot: VIL(AC)> –2V (Pulse width less than tCYC/2).
10. TPower-up: Assumes a linear ramp from 0V to VDD (min.) within 200 ms. During this time VIH< VDD and VDDQ < VDD.
Document #: 38-05437 Rev. *C
Page 7 of 12
CY7C1231F
Thermal Resistance[11]
Parameters
Description
ΘJA
Thermal Resistance
(Junction to Ambient)
ΘJC
Thermal Resistance
(Junction to Case)
Test Conditions
TQFP Typ.
Unit
Test conditions follow standard test methods and
procedures for measuring thermal impedance,
per EIA/JESD51
41.83
°C/W
9.99
°C/W
Capacitance[11]
Parameter
Description
CIN
Input Capacitance
CCLOCK
Clock Input Capacitance
CI/O
I/O Capacitance
Test Conditions
Max.
Unit
5
pF
5
pF
5
pF
TA = 25°C, f = 1 MHz,
VDD = 3.3V
VDDQ=3.3V
AC Test Loads and Waveforms
3.3V I/O Test Load
R = 317Ω
3.3V
OUTPUT
(a)
INCLUDING
JIG AND
SCOPE
90%
10%
90%
10%
GND
5 pF
VL = 1.5V
ALL INPUT PULSES
VDDQ
OUTPUT
RL = 50Ω
Z0 = 50Ω
R = 351Ω
≤ 1 ns
≤ 1 ns
(c)
(b)
Switching Characteristics Over the Operating Range [12, 13]
117 MHz
Parameter
tPOWER
Description
VDD(Typical) to the first
Access[14]
Min.
Max.
100 MHz
Min.
Max.
Unit
1
1
ms
Clock
tCYC
Clock Cycle Time
8.5
10
ns
tCH
Clock HIGH
3.0
4.0
ns
tCL
Clock LOW
3.0
4.0
ns
Output Times
tCDV
Data Output Valid after CLK Rise
tDOH
Data Output Hold after CLK Rise
2.0
2.0
ns
tCLZ
Clock to
Low-Z[15, 16, 17]
0
0
ns
tCHZ
Clock to
High-Z[15, 16, 17]
3.5
3.5
ns
tOEV
OE LOW to Output Valid
3.5
3.5
ns
tOELZ
tOEHZ
OE LOW to Output
Low-Z[15, 16, 17]
OE HIGH to Output
High-Z[15, 16, 17]
7.5
0
8.5
0
3.5
ns
ns
3.5
ns
Set-up Times
tAS
Address Set-up before CLK Rise
2.0
2.0
ns
Shaded areas contain advance information. Please contact your local Cypress sales representative for availability of this part.
Notes:
11. Tested initially and after any design or process changes that may affect these parameters.
12. Timing reference level is 1.5V when VDDQ = 3.3V.
13. Test conditions shown in (a) of AC Test Loads, unless otherwise noted.
14. This part has a voltage regulator internally; tPOWER is the time that the power needs to be supplied above VDD minimum initially before a read or write operation
can be initiated.
15. tCHZ, tCLZ,tOELZ, and tOEHZ are specified with AC test conditions shown in (b) of AC Test Loads. Transition is measured ± 200 mV from steady-state voltage.
16. At any given voltage and temperature, tOEHZ is less than tOELZ and tCHZ is less than tCLZ to eliminate bus contention between SRAMs when sharing the same
data bus. These specifications do not imply a bus contention condition, but reflect parameters guaranteed over worst case user conditions. Device is designed
to achieve Three-state prior to Low-Z under the same system conditions.
17. This parameter is sampled and not 100% tested.
Document #: 38-05437 Rev. *C
Page 8 of 12
CY7C1231F
Switching Characteristics Over the Operating Range (continued)[12, 13]
117 MHz
Parameter
Description
Min.
100 MHz
Max.
Min.
Max.
Unit
tALS
ADV/LD Set-up before CLK Rise
2.0
2.0
ns
tCENS
CEN Set-up before CLK Rise
2.0
2.0
ns
tWES
WE, BW[A:B] Set-up before CLK Rise
2.0
2.0
ns
tDS
Data Input Set-up before CLK Rise
2.0
2.0
ns
tCES
Chip Enable Set-up before CLK Rise
2.0
2.0
ns
tAH
Address Hold after CLK Rise
0.5
0.5
ns
tALH
ADV/LD Hold after CLK Rise
0.5
0.5
ns
tWEH
WE, BW[A:B] Hold after CLK Rise
0.5
0.5
ns
tCENH
CEN Hold after CLK Rise
0.5
0.5
ns
tDH
Data Input Hold after CLK Rise
0.5
0.5
ns
tCEH
Chip Enable Hold after CLK Rise
0.5
0.5
ns
Hold Times
Switching Waveforms
Read/Write Waveforms[18, 19, 20]
1
2
3
tCYC
4
5
6
7
8
9
A5
A6
A7
10
CLK
tCENS
tCENH
tCES
tCEH
tCH
tCL
CEN
CE
ADV/LD
WE
BW[A:B]
A1
ADDRESS
tAS
A2
A4
A3
tCDV
tAH
tDOH
tCLZ
DQ
D(A1)
tDS
D(A2)
Q(A3)
D(A2+1)
tOEV
Q(A4+1)
Q(A4)
tOELZ
WRITE
D(A1)
WRITE
D(A2)
D(A5)
Q(A6)
D(A7)
WRITE
D(A7)
DESELECT
tOEHZ
tDH
OE
COMMAND
tCHZ
BURST
WRITE
D(A2+1)
READ
Q(A3)
READ
Q(A4)
DON’T CARE
BURST
READ
Q(A4+1)
tDOH
WRITE
D(A5)
READ
Q(A6)
UNDEFINED
Notes:
18. For this waveform ZZ is tied LOW.
19. When CE is LOW, CE1 is LOW, CE2 is HIGH and CE3 is LOW. When CE is HIGH, CE1 is HIGH or CE2 is LOW or CE3 is HIGH.
20. Order of the Burst sequence is determined by the status of the MODE (0 = Linear, 1 = Interleaved). Burst operations are optional.
Document #: 38-05437 Rev. *C
Page 9 of 12
CY7C1231F
Switching Waveforms
NOP, STALL and Deselect Cycles[18, 19, 21]
1
2
3
A1
A2
4
5
A3
A4
6
7
8
9
10
CLK
CEN
CE
ADV/LD
WE
BW[A:B]
ADDRESS
A5
tCHZ
D(A1)
DQ
Q(A2)
Q(A3)
D(A4)
Q(A5)
tDOH
COMMAND
WRITE
D(A1)
READ
Q(A2)
STALL
READ
Q(A3)
WRITE
D(A4)
STALL
DON’T CARE
NOP
READ
Q(A5)
DESELECT
CONTINUE
DESELECT
UNDEFINED
ZZ Mode Timing[22, 23]
CLK
t ZZ
ZZ
I
t ZZREC
t ZZI
SUPPLY
I DDZZ
t RZZI
ALL INPUTS
(except ZZ)
DESELECT or READ Only
Outputs (Q)
High-Z
DON’T CARE
Ordering Information
Speed
(MHz)
100
Ordering Code
CY7C1231F-100AC
Package
Name
A101
Package Type
100-Lead 14 x 20 x 1.4 mm Thin Quad Flat Pack
Operating
Range
Commercial
Please contact your local Cypress sales representative for availability of 117-MHz speed grade option.
Notes:
21. The IGNORE CLOCK EDGE or STALL cycle (Clock 3) illustrated CEN being used to create a pause. A write is not performed during this cycle.
22. Device must be deselected when entering ZZ mode. See Truth Table for all possible signal conditions to deselect the device.
23. I/Os are in three-state when exiting ZZ sleep mode.
Document #: 38-05437 Rev. *C
Page 10 of 12
CY7C1231F
Package Diagram
100-lead Thin Plastic Quad Flatpack (14 x 20 x 1.4 mm) A101
51-85050-*A
NoBL and No Bus Latency are trademarks of Cypress Semiconductor Corporation. ZBT is a trademark of Integrated Device
Technology. All product and company names mentioned in this document are the trademarks of their respective holders.
Document #: 38-05437 Rev. *C
Page 11 of 12
© Cypress Semiconductor Corporation, 2005. 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.
CY7C1231F
Document History Page
Document Title: CY7C1231F 2-Mbit (128K x 18) Flow-through SRAM with NoBL™ Architecture
Document Number: 38-05437
REV.
ECN NO.
Issue Date
Orig. of
Change
Description of Change
**
201060
See ECN
NJY
New Data Sheet
*A
213321
See ECN
VBL
Updated Ordering Info section: shaded part number, added explanation
Shaded Selection guide and Characteristics table
*B
358314
See ECN
PCI
Changed Pin# 14, 16 and 66 from VSS, VDD and VSS to NC’s respectively in
Pin Configuration Diagram/Pin Description Table
*C
366734
See ECN
PCI
Removed IOS parameter from DC Table
Modified VOL, VOH test conditions
Modified test condition in note# 10 from VDDQ < VDD to VDDQ ≤ VDD
Document #: 38-05437 Rev. *C
Page 12 of 12
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