Cypress CY7C1372DV25, CY7C1370DV25 User Manual

a b c d
C
CY7C1370DV25 CY7C1372DV25
18-Mbit (512K x 36/1M x 18)
Pipelined SRAM with NoBL™ Architecture
Features
• Pin-compatible and functionally equivalent to ZBT™
• Internally self-timed output buffer control to eliminate the need to use asynchronous OE
• Fully registered (inputs and outputs) for pipelined operation
• Byte Write capability
• Single 2.5V core power supply (V
• 2.5V I/O power supply (V
DDQ
)
• Fast clock-to-output times — 2.6 ns (for 250-MHz device)
• Clock Enable (CEN
) pin to suspend operation
• Synchronous self-timed writes
• Available in JEDEC-standard lead-free 100-Pin TQFP, lead-free and non-lead-free 119-Ball BGA and 165-Ball FBGA packages
• IEEE 1149.1 JTAG-Compatible Boundary Scan
• Burst capability—linear or interleaved burst order
• “ZZ” Sleep Mode option and Stop Clock option
DD
)
Functional Description
The CY7C1370DV25 and CY7C1372DV25 are 2.5V, 512K x 36 and 1 Mbit x 18 Synchronous pipelined burst SRAMs with No Bus Latency™ (NoBL™) logic, respectively. They are designed to support unlimited true back-to-back Read/Write operations with no wait states. The CY7C1370DV25 and CY7C1372DV25 are equipped with the advanced (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 in systems that require frequent Write/Read transitions. The CY7C1370DV25 and CY7C1372DV25 are pin-compatible and functionally equivalent to ZBT devices.
All synchronous inputs pass through input registers controlled by the rising edge of the clock. All data outputs pass through output registers controlled by the rising edge of the clock. The clock input is qualified by the Clock Enable (CEN which when deasserted suspends operation and extends the previous clock cycle.
Write operations are controlled by the Byte Write Selects (BW
–BWd for CY7C1370DV25 and BWa–BWb for
a
CY7C1372DV25) and a Write Enable (WE
) input. All writes are
conducted with on-chip synchronous self-timed write circuitry. Three synchronous Chip Enables (CE
asynchronous Output Enable (OE
, CE2, CE3) and an
1
) 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.
) signal,
Logic Block Diagram-CY7C1370DV25 (512K x 36)
A0, A1, A
MODE
CLK
C
EN
ADV/LD
BW
a
BW
b
BW
c
BW
d
WE
OE CE1 CE2 CE3
ZZ
ADDRESS
REGISTER 0
WRITE ADDRESS
REGISTER 1
WRITE REGISTRY
AND DATA COHERENCY
CONTROL LOGIC
READ LOGIC
SLEEP
CONTROL
ADV/LD
C
WRITE ADDRESS
REGISTER 2
A1
D1D0Q1
A0
BURST LOGIC
A1' A0'
Q0
WRITE
DRIVERS
MEMORY
ARRAY
INPUT
REGISTER 1
O
S
U T
E
P
N
U T
S E
R E G
A
I
M
S T
P
E
S
R S
E
E
REGISTER 0
INPUT
O
D
U T
A
P
T
U
A
T B
S T E E R
I N G
E
DQs
U
DQP
F
DQP
F
DQP
E
DQP
R S
E
Cypress Semiconductor Corporation 198 Champion Court San Jose, CA 95134-1709 408-943-2600 Document #: 38-05558 Rev. *D Revised June 29, 2006
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C
Logic Block Diagram-CY7C1372DV25 (1M x 18)
CY7C1370DV25 CY7C1372DV25
CLK
EN
A0, A1, A
MODE
C
ADV/LD
BW
a
BW
b
WE
ADDRESS
REGISTER 0
WRITE ADDRESS
REGISTER 1
A1
D1D0Q1
A0
ADV/LD
C
WRITE ADDRESS
REGISTER 2
WRITE REGISTRY
AND DATA COHERENCY
CONTROL LOGIC
BURST LOGIC
Q0
A1' A0'
WRITE
DRIVERS
MEMORY
ARRAY
INPUT
REGISTER 1
O U T P
S
U
E
T
N
S
R
E
E G
A
I
M
S
P
T
S
E R
S
E
E
INPUT
REGISTER 0
O U T P
D
U
A
T
T A
B U
S
F
T
F
E
E
E
R
R
S
I N G
DQs DQP DQP
E
E
OE
CE1
READ LOGIC
CE2 CE3
ZZ
Sleep
Control
Selection Guide
250 MHz 200 MHz 167 MHz Unit
Maximum Access Time 2.6 3.0 3.4 ns Maximum Operating Current 350 300 275 mA Maximum CMOS Standby Current 70 70 70 mA
Document #: 38-05558 Rev. *D Page 2 of 27
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Pin Configurations
a
100-Pin TQFP Pinout
CY7C1370DV25 CY7C1372DV25
DQPc
DQc DQc
V
DDQ
V
SS
DQc DQc
DQc DQc
V
SS
V
DDQ
DQc
DQc
NC
V
DD
NC V
SS
DQd DQd
V
DDQ
V
SS
DQd DQd DQd DQd V
SS
V
DDQ
DQd DQd
DQPd
1CE2
A
A
CE
BWd
BWc
3
CE
VDDV
SS
CLKWECEN
OE
BWa
BWb
100999897969594939291908988878685848382
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
CY7C1370DV25
(512K × 36)
17 18 19 20 21 22 23 24 25 26 27 28 29 30
31323334353637383940414243444546474849
AAA
MODE
0
A
A1A
SS
DD
V
V
NC(144)
NC(288)
NC(72)
AAA
A
NC(36)
ADV/LD
A
A
A
A
81
DDQ SS
SS
DDQ
SS
DD
DDQ
SS
SS DDQ
NC NC NC
V
DDQ
V
NC
NC DQb DQb
V
SS
V
DDQ
DQb DQb
NC
V
DD
NC
V DQb DQb
V
DDQ
V DQb
DQb
DQPb
NC
V
V
DDQ
NC NC NC
SS
SS
SS
SS
DQPb
80
DQb
79
DQb
78
V
77
V
76
DQb
75
DQb
74
DQb
73
DQb
72
V
71
V
70
DQb
69
DQb
68
V
67
NC
66
V
65
ZZ
64
DQa
63
DQa
62
V
61
V
60
DQa
59
DQa
58
DQa
57
DQa
56
V
55
V
54
DQa
53
DQa
52
DQPa
51
50
1CE2
A
A
CE
100999897969594939291908988878685848382
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
31323334353637383940414243444546474849
bBWa
3
SS
VDDV
CE
BW
NC
NC
CLKWECEN
CY7C1372DV25
(1M × 18)
OE
ADV/LD
A
A
A
A
81
A
80
NC
79
NC
78
V
77
DDQ
V
SS
76
NC
75
DQP
74
DQa DQa V
SS
V
DDQ
DQa DQa V
SS
NC V
DD
ZZ DQa
DQa V
DDQ
V
SS
DQa DQa NC NC V
SS
V
DDQ
NC NC NC
73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51
50
A
A
A
A
AAA
MODE
1A0
A
AAA
A
DD
SS
V
V
NC(144)
NC(288)
A
NC(36)
NC(72)
A
A
Document #: 38-05558 Rev. *D Page 3 of 27
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Pin Configurations (continued)
CY7C1370DV25 CY7C1372DV25
A B
C D
E F G H
J K L M N P
R T U
A B C
D E F G
H J
K L
M N
P
R
T
U
V
DDQ
NC/576M
NC/1G
DQ
c
DQ
c
V
DDQ
DQ
c
DQ
c
V
DDQ
DQ
d
DQ
d
V
DDQ
DQ
d
DQ
d
NC/144M
NC
V
DDQ
V
DDQ
NC/576M
NC/1G
b
NC
V
DDQ
NC
DQ
b
V
DDQ
NC
DQ
b
V
DDQ
DQ
b
NC
NC/144M
NC/72M
V
DDQ
119-Ball BGA
Pinout
CY7C1370DV25 (512K × 36)
2345671
AA AAAV
CE
2
A
DQP
c
DQ
c
DQ
c
DQ
c
DQ
c
V
DD
DQ
d
DQ
d
DQd
DQ
d
DQP
d
A
NC/72M
TMS
A A
V
SS
V
SS
V
SS
BW
V
SS
NC
V
SS
BW
V
SS
V
SS
V
SS
MODE
A
ADV/LD
V
DD
NC DQP
CE
1
OE
c
A
WE V
DD
CLK
d
NC
CEN
A1 A0 V
V
DD
A NC/36M
TCK
ACE3NC AANC
V
SS
V
SS
V
SS
BW
V
SS
NC V
V
SS
BW
V
SS
V
SS SS
DQ
b
DQ
b
DQ DQ
DQ DQ
DQ DQ
b b
DD
a a
a a
b
a
DQP
NC
A
NCTDI TDO V
DDQ
DQ
b
a
DQ
V
DQ DQ
V
DQ DQ
V
DQ DQ
b b
DDQ
b b
DDQ
a a
DDQ
a a
NC/288MA
ZZ
DDQ
CY7C1372DV25 (1M x 18)
2345671
AA AAAV
CE
A
NCDQ
DQ
NC
DQ
NC
V
DD
DQ
NC
DQ
NC
DQP
A A
TMS
2
b
b
b
b
b
A A
V
SS
V
SS
V
SS
BW
V
SS
NC
V
SS
NC
V
SS
V
SS
V
SS
MODE
A
b
ADV/LD
V
DD
NC NCDQP
CE
1
OE
A AANC
V
SS
V
SS
V
SS
CE
NC
DQ
3
a
ANCNC
WE
V
DD
CLK
NC NC
CEN
A1 A0 V
V
DD
NC/36M
V
SS
NC V
SS
BW
V
SS
V
SS SS
NC
A
TCK
a
DQ
a
DD
NCV
DQ
a
NC V
DQ
a
NC
A A
NCTDI TDO V
a
DDQ
NC
DQ
a
V
DDQ
DQ
a
NC
V
DDQ
DQ
a
DDQ
NC
DQ
a
NC/288M
ZZ
DDQ
Document #: 38-05558 Rev. *D Page 4 of 27
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Pin Configurations (continued)
234 5671
A B C
D E F G
H J K L
M N
P
R
A B C
D E
F G H
J K
L
M
N P
R
NC/576M
NC/1G
DQP
c
DQ
c
DQ
c
DQ
c
DQ
c
NC
DQ
d
DQ
d
DQ
d
DQ
d
DQP
d
NC/144M
MODE
NC/576M
NC/1G
NC NC
NC V NC NC
NC
DQ
b
DQ
b
DQ
b
DQ
b
DQP
b
NC/144M
MODE
A A
NC
DQ
c
DQ
c
DQ
c
DQ
c
NC
DQ
d
DQ
d
DQ
d
DQ
d
NC
NC/72M NC/36M
2345671
A A
NC
DQ
b
DQ
b
DQ
b
DQ
b
NC NC NC NC
NC NC
NC/72M NC/36M
CE
CE2
V
DDQ
V
DDQ
V
DDQ
V
DDQ
V
DDQ
NC
V
DDQ
V
DDQ
V
DDQ
V
DDQ
V
DDQ
CE
CE2 V V V V V
NC
V V V V V
A A
DDQ DDQ
DDQ DDQ DDQ
DDQ DDQ DDQ DDQ DDQ
A A
CY7C1370DV25 CY7C1372DV25
165-Ball FBGA Pinout
CY7C1370DV25 (512K × 36)
891011
V V
V V V
V V V V V
A AADV/LD
DDQ DDQ
DDQ DDQ DDQ
NC
DDQ DDQ DDQ DDQ DDQ
A
A
A
NC DQP
DQ
b
DQ
b
DQ
b
DQ
b
NC
DQ
a
DQ
a
DQ
a
DQ
a
NC
A
BW
1
BW
V
SS
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
SS
A
A
BW
c
BW
d
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
NC
TDI
TMS
CE
b
CLK
a
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
NC A1
CEN
3
WE
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
NC
TDO TCKA0
OE A
V
SS
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
SS
A
A
CY7C1372DV25 (1M × 18)
891011
BW
1
b
NC
NC BW
V
SS
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
SS
A
A
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
NC
TDI
TMS
CE CLK
a
V
SS
V
SS SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
V
SS
NC
A1
CEN
3
WE
V V
V V V
V V V V
V
NC
TDO
TCKA0
SS SS
SS SS SS
SS SS SS SS
SS
ADV/LD
OE
V
SS
V
DD
V
DD
V
DD
V
DD
V
DD DD
V
DD
V
DD
V
DD
V
SS
A
A
A A
A
V
DDQ
V
DDQ
V
DDQ
V
DDQ
V
DDQ
NC
V
DDQ
V
DDQ
V
DDQ
V
DDQ
V
DDQ
A
A
A NC DQP NC NC NC NC
NC
DQ
a
DQ
a
DQ
a
DQ
a
NC
A
NC NC
b
DQ
b
DQ
b
DQ
b
DQ
b
ZZ
DQ
a
DQ
a
DQ
a
DQ
a
DQP
a
NC/288M
AA
A
NC
a
DQ
a
DQ
a
DQ
a
DQ
a
ZZ NCV NC NC
NC NC
NC/288M
AA
Document #: 38-05558 Rev. *D Page 5 of 27
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CY7C1370DV25 CY7C1372DV25
Pin Definitions
Pin Name I/O Type Pin Description
A0 A1 A
BW
a
BW
b
BW
c
BW
d
WE Input-
ADV/LD Input-
CLK Input-
CE
1
CE
2
CE
3
OE Input-
CEN Input-
DQ
S
DQP
X
MODE Input Strap Pin Mode Input. Selects the burst order of the device. Tied HIGH selects the interleaved burst order.
TDO JT AG ser ial
TDI JT AG ser ial
TMS Test Mode
TCK JTAG-Clock Clock input to the JTAG circuitry.
Input-
Synchronous
Input-
Synchronous
Synchronous
Synchronous
Clock Input-
Synchronous
Input-
Synchronous
Input-
Synchronous
Asynchronous
Synchronous
I/O-
Synchronous
I/O-
Synchronous
output
Synchronous
input
Synchronous
Select
Synchronous
Address Inputs used to select one of the address locations. Sampled at the rising edge of the CLK.
Byte Write Select Inputs, active LOW. Qualified with WE to conduct writes to the SRAM. Sampled on the rising edge of CLK. BW
controls DQc and DQPc, BWd controls DQd and DQPd.
BW
c
controls DQa and DQPa, BWb controls DQb and DQPb,
a
Write Enable Input, active LOW. Sampled on the rising edge of CLK if CEN is active LOW . This signal must be asserted LOW to initiate a write sequence.
Advance/Load Input used to advance the on-chip address counter or load a new address. When HIGH (and CEN new address can be loaded into the device for an access. After being deselected, ADV/LD
is asserted LOW) the internal burst counter is advanced. When LOW, a
should
be driven LOW in order to load a new address. Clock Input. Used to capture all synchronous inputs to th e de vi ce . CL K is qu a l ified with CEN.
CLK is only recognized if CEN
is active LOW.
Chip Enable 1 Input, active LOW. Sampled on the rising edge of CLK. Used in conjunction with CE
and CE3 to select/deselect the device.
2
Chip Enable 2 Input, active HIGH. Sampled on the rising edge of CLK. Used in conjunction with CE
and CE3 to select/deselect the device.
1
Chip Enable 3 Input, active LOW. Sampled on the rising edge of CLK. Used in conjunction with
and CE2 to select/deselect the device.
CE
1
Output Enable, active LOW. Combined with the 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 and when the device has been deselected.
Clock Enable Input, active LOW. When asserted LOW the clock signal is recognized by the SRAM. When deasserted HIGH the clock signal is masked. Since deasserting CEN deselect the device, CEN
can be used to extend the previous cycle when required.
does not
Bidirectional Data I/O lines. As inputs, they feed into an on-chip data register that is triggered by the rising edge of CLK. As outputs, they deliver the data contained in the memory location specified by A controlled by OE as outputs. When HIGH, DQ automatically three-stated during the data portion of a write sequence, during the first clock when
during the previous clock rise of the read cycle. The direction of the pins is
[17:0]
and the internal control logic. When OE is asserted LOW, the pins can behave
–DQd are placed in a three-state condition. The outputs are
a
emerging from a deselected state, and when the device is deselected, regardless of the state of OE
.
Bidirectional Data Parity I/O lines. Functionally , these signals are identical to DQs. During write sequences, DQP and DQP
d
is controlled by BWa, DQPb is controlled by BWb, DQPc is controlled by BWc,
a
is controlled by BWd.
Pulled LOW selects the linear burst order. MODE should not change states during operation. When left floating MODE will default HIGH, to an interleaved burst order.
Serial data-out to the JTAG circuit. Delivers data on the negative edge of TCK.
Serial data-In to the JTAG circuit. Sampled on the rising edge of TCK.
This pin controls the Test Access Port state machine. Sampled on the rising edge of TCK.
Document #: 38-05558 Rev. *D Page 6 of 27
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Pin Definitions (continued)
Pin Name I/O Type Pin Description
V
DD
V
DDQ
V
SS
NC No connects. This pin is not connected to the die. NC/(36M, 72M,
144M, 288M, 576M, 1G)
ZZ Input-
Power Supply Power supply inputs to the core of the device.
I/O Power
Power supply for the I/O circuitry.
Supply
Ground Ground for the device. Should be connected to ground of the system.
These pins are not connected. They will be used for expansion to the 36M, 72M, 144M, 288M,
576M, and 1G densities.
ZZ “Sleep” Input. This active HIGH input places the device in a non-time critical “sleep”
Asynchronous
condition with data integrity preserved. For normal operation, this pin has to be LOW or left floating. ZZ pin has an internal pull-down.
CY7C1370DV25 CY7C1372DV25
Introduction
Functional Overview
The CY7C1370DV25 and CY7C1372DV25 are synchronous-pipelined Burst NoBL SRAMs desig ned 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 signal is not recognized and all internal states are maintained. All synchronous operations are qualified with CEN. All data outputs pass through output registers controlled by the rising edge of the clock. Maximum access delay from the clock rise (t
) is 2.6 ns (250-MHz device).
CO
Accesses can be initiated by asserting all three Chip Enables (CE
, CE2, CE3) active at the rising edge of the clock. If Clock
1
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 conduct byte write operations.
Write operations are qualified by the Write Enable (WE writes are simplified with on-chip synchronous self-timed write circuitry.
Three synchronous Chip Enables (CE asynchronous Output Enable (OE 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 and CE signal WE
are ALL asserted active, (3) the Write Enable input
3
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 core and control logic. The control logic determines that a read access is in progress and allows the requested data to propagate to the input of the output register. At the rising edge of the next clock the requested data is allowed to propagate through the output register and onto the data bus within 2.6 ns (250-MHz device) provided OE clock of the read access the output buffers are controlled by OE
and the internal control logic. OE must be driven LOW in
). If CEN is HIGH, the clock
). BWX can be used to
). All
, CE2, CE3) and an
1
) simplify depth expansion.
is asserted LOW, (2) CE1, CE2,
is active LOW. After the first
order for the device to drive out the requested data. During the second clock, a subsequent operation (Read/Write/Deselect) can be initiated. Deselecting the device is also pipelined. Therefore, when the SRAM is deselected at clock rise by one of the chip enable signals, its output will three-state following the next clock rise.
Burst Read Accesses
The CY7C1370DV25 and CY7C1372DV25 have 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. The sequence of the burst counter i s 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 enables 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 access are initiated when the following conditions are satisfied at clock rise: (1) CEN and CE is asserted LOW. The address presented is loaded into the
are ALL asserted active, and (3) the write signal WE
3
is asserted LOW, (2) CE1, CE2,
Address Register. The write signals are latched into the Control Logic block.
On the subsequent clock rise the data lines are automatically three-stated regardless of the state of the OE allows the external logic to present the data on DQ (DQ for CY7C1372DV25). In addition, the address for the subse-
a,b,c,d
/DQP
for CY7C1370DV25 and DQ
a,b,c,d
input signal. This
and DQP
/DQP
a,b
a,b
quent access (Read/Write/Deselect) is latched into the Address Register (provided the appropriate control signals are asserted).
On the next clock rise the data presented to DQ (DQ CY7C1372DV25) (or a subset for byte write operations, see
a,b,c,d
/DQP
for CY7C1370DV25 & DQ
a,b,c,d
a,b
/DQP
and DQP
a,b
for
Write Cycle Description table for details) inputs is latched into the device and the write is complete.
The data written during the write operation is controlled by BW (BW
for CY7C1370DV25 and BW
a,b,c,d
for CY7C1372DV25)
a,b
Document #: 38-05558 Rev. *D Page 7 of 27
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CY7C1370DV25 CY7C1372DV25
signals. The CY7C1370DV25/CY7C1372DV25 provides byte write capability that is described in the Write Cycle Description table. Asserting the Write Enable input (WE) with the selected Byte Write Select (BW
) 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 CY7C1370DV25 and CY7C1372DV25 are common I/O devices, data should not be driven into the device while the outputs are active. The Output Enable (OE deasserted HIGH before presenting data to the DQ (DQ for CY7C1372DV25) inputs. Doing so will three-state the
a,b,c,d
/DQP
for CY7C1370DV25 and DQ
a,b,c,d
output drivers. As a safety precaution, DQ (DQ for CY7C1372DV25) are automatically three-stated during the
a,b,c,d
/DQP
for CY7C1370DV25 and DQ
a,b,c,d
data portion of a write cycle, regardless of the state of OE
) can be
and DQP
/DQP
a,b
and DQP
/DQP
a,b
a,b
a,b
.
Burst Write Accesses
The CY7C1370DV25/CY7C1372DV25 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 (CE
) and WE inputs are ignored and the burst counter is incre-
CE
3
mented. The correct BW BW
for CY7C1372DV25) inputs must be driven in each
a,b
cycle of the burst write in order to write the correct bytes of
(BW
for CY7C1370DV25 and
a,b,c,d
, CE2, and
1
data.
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. CE for the duration of t
, CE2, and CE3, must remain inactive
1
after the ZZ input returns LOW.
ZZREC
Interleaved Burst Address Table (MODE = Floating or V
First
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
Second
Address
DD
)
Address
Third
Fourth
Address
Linear Burst Address Table (MODE = GND)
First
Address
A1,A0 A1,A0 A1,A0 A1,A0
00 01 10 11 01 10 11 00 10 11 00 01 11 00 01 10
Second
Address
Third
Address
Fourth
Address
ZZ Mode Electrical Characteristics
Parameter Description Test Conditions Min. Max. Unit
I
DDZZ
t
ZZS
t
ZZREC
t
ZZI
t
RZZI
Sleep mode standby current ZZ > VDD − 0.2V 80 mA Device operation to ZZ ZZ > VDD 0.2V 2t ZZ recovery time ZZ < 0.2V 2t
CYC
ZZ active to sleep current This parameter is sampled 2t
CYC
CYC
ZZ Inactive to exit sleep current This parameter is sampled 0 ns
ns ns ns
Document #: 38-05558 Rev. *D Page 8 of 27
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CY7C1370DV25 CY7C1372DV25
Truth Table
[1, 2, 3, 4, 5, 6, 7]
Address
Operation
Used CE ZZ ADV/LD WE BWxOE CEN CLK DQ
Deselect Cycle None H L L X X X L L-H Tri-state Continue Deselect Cycle None X L H X X X L L-H Tri-state Read Cycle (Begin Burst) External L L L H X L L L-H Data Out (Q) Read Cycle (Continue Burst) Next X L H X X L L L-H Data Out (Q) NOP/Dummy Read (Begin Burst) External L L L H X H L L-H Tri-state Dummy Read (Continue Burst) Next X L H X X H L L-H Tri-state Write Cycle (Begin Burst) External L L L L L X L L-H Data In (D) Write Cycle (Continue Burst) Next X L H X L X L L-H Data In (D) NOP/Write Abort (Begin Burst) None L L L L H X L L-H Tri-state Write Abort (Continue Burst) Next X L H X H X L L-H Tri-state Ignore Clock Edge (Stall) Current X L X X X X H L-H – Sleep Mode None X H X X X X X X Tri-state
Partial Write Cycle Description
Function (CY7C1370DV25) WE BW
[1, 2, 3, 8]
d
BW
c
BW
b
BW
a
Read H X X X X Write – No bytes written L H H H H Write Byte a – (DQ Write Byte b – (DQ
and DQPa) LHHHL
a
and DQPb)LHHLH
b
Write Bytes b, a L H H L L Write Byte c – (DQ
and DQPc)LHLHH
c
Write Bytes c, a L H L H L Write Bytes c, b L H L L H Write Bytes c, b, a L H L L L Write Byte d – (DQ
and DQPd)LLHHH
d
Write Bytes d, a L L H H L Write Bytes d, b LLHLH Write Bytes d, b, a L L H L L Write Bytes d, c L L L H H Write Bytes d, c, a L L L H L Write Bytes d, c, b L L L L H Write All Bytes L L L L L
Notes:
1. X = “Don't Care”, H = Logic HIGH, L = Logic LOW, CE signifies that the desired byte write selects are asserted, see Write Cycle Descript i on table for details.
2. Write is defined by WE
3. When a write cycle is detected, all I/Os are tri-stated, even during byte writes.
4. The DQ and DQP pins are controlled by the current cycle and the OE
= H inserts wait states.
5. CEN
6. Device will power-up deselected and the I/Os in a tri-state condition, regardless of OE
is asynchronous and is not sampled with the clock rise. It is masked internally during write cycles.During a read cycle DQs and DQPX = Three-state when
7. OE OE
is inactive or when the device is deselected, and DQs = data when OE is active.
8. Table only lists a partial listing of the byte write combinations. Any Combina tion of BW
and BWX. See Write Cycle Description table for details.
stands for ALL Chip Enables active. BWx = L signifies at least one Byt e Write Select is active, BWx = Valid
signal.
.
is valid. Appropriate write will be done based on which byte write is active.
X
Document #: 38-05558 Rev. *D Page 9 of 27
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