CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
72-Mbit QDR™-II+ SRAM 4-Word Burst
Architecture (2.0 Cycle Read Latency)
Features
Configurations
■ Separate independent read and write data ports
❐ Supports concurrent transactions
With Read Cycle Latency of 2.0 cycles:
CY7C1541V18 – 8M x 8
■ 375 MHz clock for high bandwidth
CY7C1556V18 – 8M x 9
CY7C1543V18 – 4M x 18
■ 4-word burst for reducing address bus frequency
CY7C1545V18 – 2M x 36
■ DoubleDataRate(DDR)interfacesonbothreadandwriteports
(data transferred at 750 MHz) at 375 MHz
Functional Description
■ Available in 2.0 clock cycle latency
The CY7C1541V18, CY7C1556V18, CY7C1543V18, and
CY7C1545V18 are 1.8V Synchronous Pipelined SRAMs,
equipped with QDR-II+ architecture. Similar to QDR-II archi-
tecture, QDR-II+ SRAMs consists of two separate ports: the read
port and the write port to access the memory array. The read port
has dedicated data outputs to support read operations and the
write port has dedicated data inputs to support write operations.
QDR-II+ architecture has separate data inputs and data outputs
to completely eliminate the need to “turn-around” the data bus
that exists with common IO devices. Each port is accessed
through a common address bus. Addresses for read and write
addresses are latched on alternate rising edges of the input (K)
clock. Accesses to the QDR-II+ read and write ports are
completely independent of one another. To maximize data
throughput, both read and write ports are equipped with DDR
interfaces. Each address location is associated with four 8-bit
words (CY7C1541V18), 9-bit words (CY7C1556V18), 18-bit
words (CY7C1543V18), or 36-bit words (CY7C1545V18) that
burst sequentially into or out of the device. Because data is trans-
ferred into and out of the device on every rising edge of both input
clocks (K and K), memory bandwidth is maximized while simpli-
fying system design by eliminating bus “turn-arounds”.
■ Two input clocks (K and K) for precise DDR timing
❐ SRAM uses rising edges only
■ Echo clocks (CQ and CQ) simplify data capture in high-speed
systems
■ Data valid pin (QVLD) to indicate valid data on the output
■ Single multiplexed address input bus latches address inputs
for both read and write ports
■ Separate port selects for depth expansion
■ Synchronous internally self-timed writes
■ Available in x8, x9, x18, and x36 configurations
■ Full data coherency, providing most current data
■ Core V = 1.8V ± 0.1V; IO V
= 1.4V to V
DD
DD
DDQ
■ HSTL inputs and variable drive HSTL output buffers
■ Available in 165-Ball FBGA package (15 x 17 x 1.4 mm)
■ Offered in both Pb-free and non Pb-free packages
■ JTAG 1149.1 compatible test access port
Depth expansion is accomplished with port selects, which
enables each port to operate independently.
■ Delay Lock Loop (DLL) for accurate data placement
All synchronous inputs pass through input registers controlled by
the K or K input clocks. All data outputs pass through output
registers controlled by the K or K input clocks. Writes are
conducted with on-chip synchronous self-timed write circuitry.
Selection Guide
Description
Maximum Operating Frequency
Maximum Operating Current
375 MHz
375
333 MHz
333
300 MHz
300
Unit
MHz
mA
x8
x9
1300
1300
1300
1370
1200
1200
1200
1230
1100
1100
x18
x36
1100
1140
Note
1. The QDR consortium specification for V
is 1.5V + 0.1V. The Cypress QDR devices exceed the QDR consortium specification and are capable of supporting
DDQ
V
= 1.4V to V
.
DDQ
DD
Cypress Semiconductor Corporation
Document Number: 001-05389 Rev. *F
•
198 Champion Court
•
San Jose, CA 95134-1709
•
408-943-2600
Revised March 06, 2008
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Logic Block Diagram (CY7C1543V18)
18
D
[17:0]
Write Write Write Write
Reg
Reg Reg Reg
20
Address
Register
A
(19:0)
20
Address
Register
A
(19:0)
RPS
K
Control
Logic
CLK
Gen.
K
DOFF
Read Data Reg.
CQ
CQ
72
36
V
REF
18
18
18
18
Reg.
Reg.
Reg.
Control
Logic
WPS
BWS
18
36
Q
[17:0]
[1:0]
QVLD
Logic Block Diagram (CY7C1545V18)
36
D
[35:0]
Write Write Write Write
Reg
Reg Reg Reg
19
Address
Register
A
(18:0)
19
Address
Register
A
(18:0)
RPS
K
Control
Logic
CLK
Gen.
K
DOFF
Read Data Reg.
CQ
CQ
144
72
V
REF
36
36
36
36
Reg.
Reg.
Reg.
Control
Logic
WPS
BWS
36
72
Q
[35:0]
[3:0]
QVLD
Document Number: 001-05389 Rev. *F
Page 3 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Pin Configuration
The pin configuration for CY7C1541V18, CY7C1556V18, CY7C1543V18, and CY7C1545V18 follow.
165-Ball FBGA (15 x 17 x 1.4 mm) Pinout
CY7C1541V18 (8M x 8)
1
CQ
NC
NC
NC
NC
NC
NC
DOFF
NC
NC
NC
NC
NC
NC
TDO
2
3
4
WPS
A
5
6
K
7
8
RPS
A
9
10
A
11
CQ
Q3
D3
NC
Q2
NC
NC
ZQ
D1
NC
Q0
D0
NC
NC
TDI
A
B
C
D
E
F
A
A
NWS
NC/144M
A
1
NC
NC
D4
NC
NC
D5
NC
NC
NC
Q4
NC
Q5
NC/288M
A
K
NWS
A
NC
NC
NC
NC
NC
NC
NC
NC
NC
D2
NC
NC
0
V
V
NC
V
V
SS
SS
SS
SS
V
V
V
V
V
V
V
V
V
V
V
V
V
SS
SS
DD
DD
DD
DD
DD
SS
SS
SS
SS
SS
SS
SS
SS
SS
SS
SS
DD
DD
DD
DD
DD
V
V
V
V
V
V
V
V
V
V
V
V
V
V
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
V
V
V
V
V
V
V
V
V
V
G
H
J
V
V
V
V
REF
REF
DDQ
DDQ
NC
NC
NC
Q1
K
L
NC
Q6
NC
D6
NC
NC
Q7
A
NC
NC
NC
NC
NC
A
NC
NC
V
V
V
V
SS
SS
SS
SS
M
N
P
R
NC
D7
V
V
NC
SS
SS
SS
V
A
A
A
A
A
A
A
V
NC
SS
NC
TCK
A
A
QVLD
NC
A
A
NC
TMS
CY7C1556V18 (8M x 9)
1
CQ
NC
NC
NC
NC
NC
NC
DOFF
NC
NC
NC
NC
NC
NC
TDO
2
3
4
5
NC
6
K
7
8
9
10
A
11
CQ
Q4
D4
NC
Q3
NC
NC
ZQ
D2
NC
Q1
D1
NC
Q0
TDI
A
B
C
D
E
F
A
A
WPS
A
NC/144M
RPS
A
A
NC
NC
D5
NC
NC
D6
NC
NC
NC
Q5
NC
Q6
NC/288M
A
K
BWS
A
NC
NC
NC
NC
NC
NC
NC
NC
NC
D3
NC
NC
0
V
V
NC
V
V
SS
SS
SS
SS
V
V
V
V
V
V
V
V
V
V
V
V
V
SS
SS
DD
DD
DD
DD
DD
SS
SS
SS
SS
SS
SS
SS
SS
SS
SS
SS
DD
DD
DD
DD
DD
V
V
V
V
V
V
V
V
V
V
V
V
V
V
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
V
V
V
V
V
V
V
V
V
V
G
H
J
V
V
V
V
REF
REF
DDQ
DDQ
NC
NC
Q7
NC
NC
Q2
NC
NC
NC
NC
D0
K
L
NC
D7
NC
NC
Q8
A
NC
NC
NC
NC
NC
A
V
V
SS
SS
SS
SS
M
N
P
R
NC
D8
V
V
V
V
SS
SS
SS
V
A
A
A
A
A
A
A
V
SS
NC
TCK
A
A
QVLD
NC
A
A
TMS
Note
2. NC/144M and NC/288M are not connected to the die and can be tied to any voltage level.
Document Number: 001-05389 Rev. *F
Page 4 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Pin Configuration (continued)
[2]
The pin configuration for CY7C1541V18, CY7C1556V18, CY7C1543V18, and CY7C1545V18 follow.
165-Ball FBGA (15 x 17 x 1.4 mm) Pinout
CY7C1543V18 (4M x 18)
1
CQ
NC
NC
NC
NC
NC
NC
DOFF
NC
NC
NC
NC
NC
NC
TDO
2
NC/144M
Q9
3
4
WPS
A
5
BWS
NC
A
6
K
7
8
RPS
A
9
10
A
11
CQ
Q8
D8
D7
Q6
Q5
D5
ZQ
D4
Q3
Q2
D2
D1
Q0
TDI
A
B
C
D
E
F
A
NC/288M
A
1
D9
K
BWS
A
NC
NC
NC
NC
NC
NC
NC
Q7
NC
D6
NC
NC
0
NC
D10
Q10
Q11
D12
Q13
V
V
NC
V
V
SS
SS
SS
SS
D11
V
V
V
V
V
V
V
V
V
V
V
V
V
SS
SS
DD
DD
DD
DD
DD
SS
SS
SS
SS
SS
SS
SS
SS
SS
SS
SS
DD
DD
DD
DD
DD
NC
V
V
V
V
V
V
V
V
V
V
V
V
V
V
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
Q12
D13
V
V
V
V
V
V
V
V
V
V
G
H
J
V
V
V
V
REF
REF
DDQ
DDQ
NC
NC
D14
NC
Q4
K
L
Q14
D15
D16
Q16
Q17
A
NC
NC
NC
NC
NC
A
D3
NC
Q1
Q15
NC
V
V
V
V
SS
SS
SS
SS
M
N
P
R
V
V
SS
SS
SS
D17
NC
V
A
A
A
A
A
A
A
V
NC
D0
SS
A
A
QVLD
NC
A
A
TCK
TMS
CY7C1545V18 (4M x 36)
1
2
NC/288M
Q18
3
4
5
BWS
BWS
A
6
K
7
BWS
BWS
A
8
9
10
NC/144M
Q17
11
CQ
Q8
D8
D7
Q6
Q5
D5
ZQ
D4
Q3
Q2
D2
D1
Q0
TDI
A
B
C
D
E
F
CQ
A
WPS
A
RPS
A
A
2
3
1
0
Q27
D27
D28
Q29
Q30
D30
DOFF
D31
Q32
Q33
D33
D34
Q35
TDO
D18
D19
Q19
Q20
D21
Q22
K
D17
D16
Q16
Q15
D14
Q13
Q28
V
V
NC
V
V
Q7
SS
SS
SS
SS
D20
V
V
V
V
V
V
V
V
V
V
V
V
V
D15
SS
SS
DD
DD
DD
DD
DD
SS
SS
SS
SS
SS
SS
SS
SS
SS
SS
SS
DD
DD
DD
DD
DD
D29
V
V
V
V
V
V
V
V
V
V
V
V
V
V
D6
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
DDQ
Q21
V
V
V
V
V
V
V
V
V
V
Q14
G
H
J
D22
D13
V
V
V
V
REF
REF
DDQ
DDQ
Q31
D32
Q24
Q34
D26
D35
TCK
D23
D12
Q4
D3
K
L
Q23
D24
D25
Q25
Q26
A
Q12
D11
D10
Q10
Q9
V
V
Q11
Q1
SS
SS
SS
SS
M
N
P
R
V
V
V
V
SS
SS
SS
V
A
A
A
A
A
A
A
V
D9
SS
A
A
QVLD
NC
A
A
D0
A
TMS
Document Number: 001-05389 Rev. *F
Page 5 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Pin Definitions
Pin Name
IO
Pin Description
D
Input-
Synchronous
Data Input Signals. Sampled on the rising edge of K and K clocks
.
when valid write operations are active
[x:0]
CY7C1541V18 − D
[7:0]
CY7C1556V18 − D
[8:0]
CY7C1543V18 − D
[17:0]
CY7C1545V18 − D
[35:0]
WPS
Input-
Write Port Select − Active LOW. Sampled on the rising edge of the K clock. When asserted active, a
Synchronous write operation is initiated. Deasserting deselects the write port. Deselecting the write port ignores D
.
[x:0]
NWS ,
Input-
Synchronous K clocks when write operations are active. Used to select which nibble is written into the device during
the current portion of the write operations. NWS controls D and NWS controls D
Nibble Write Select 0, 1 − Active LOW (CY7C1541V18 Only). Sampled on the rising edge of the K and
0
NWS ,
1
.
[7:4]
0
[3:0]
1
All the Nibble Write Selects are sampled on the same edge as the data. Deselecting a Nibble Write Select
ignores the corresponding nibble of data and it is not written into the device.
BWS ,
Input-
Synchronous
Byte Write Select 0, 1, 2 and 3 − Active LOW.
Sampled on the rising edge of the K and K clocks when
write operations are active. Used to select which byte is written into the device during the current portion
of the write operations. Bytes not written remain unaltered.
0
BWS ,
1
BWS ,
2
BWS
CY7C1556V18 − BWS controls D
3
0
[8:0]
[8:0]
[8:0]
CY7C1543V18 − BWS controls D
and BWS controls D
0
1
[17:9].
,
CY7C1545V18 − BWS controls D
, BWS controls D
0
1
[17:9]
BWS controls D
and BWS controls D
2
[26:18]
3
[35:27].
All the Byte Write Selects are sampled on the same edge as the data. Deselecting a Byte Write Select
ignores the corresponding byte of data and it is not written into the device
.
A
Input-
Address Inputs. Sampled on the rising edge of the K clock during active read and write operations. These
Synchronous address inputs are multiplexed for both read and write operations. Internally, the device is organized as
8M x 8 (4 arrays each of 2M x 8) for CY7C1541V18, 8M x 9 (4 arrays each of 2M x 9) for CY7C1556V18,
4M x 18 (4 arrays each of 1M x 18) for CY7C1543V18 and 2M x 36 (4 arrays each of 512K x 36) for
CY7C1545V18. Therefore, only 21 address inputs are needed to access the entire memory array of
CY7C1541V18 and CY7C1556V18, 20 address inputs for CY7C1543V18 and 19 address inputs for
CY7C1545V18. These inputs are ignored when the appropriate port is deselected.
Q
Outputs-
Synchronous data is driven out on the rising edge of the K and K clocks during read operations. On deselecting the
read port, Q are automatically tri-stated.
Data Output Signals. These pins drive out the requested data when the read operation is active. Valid
[x:0]
[x:0]
CY7C1541V18 − Q
CY7C1556V18 − Q
CY7C1543V18 − Q
CY7C1545V18 − Q
[7:0]
[8:0]
[17:0]
[35:0]
RPS
Input-
Read Port Select − Active LOW. Sampled on the rising edge of positive input clock (K). When active, a
Synchronous read operation is initiated. Deasserting deselects the read port. When deselected, the pending access is
allowed to complete and the output drivers are automatically tri-stated following the next rising edge of
the K clock. Each read access consists of a burst of four sequential transfers.
QVLD
K
Valid output Valid Output Indicator. The Q Valid indicates valid output data. QVLD is edge aligned with CQ and CQ.
indicator
Input-
Clock
Positive Input Clock Input. The rising edge of K is used to capture synchronous inputs to the device
and to drive out data through Q . All accesses are initiated on the rising edge of K.
[x:0]
K
Input-
Clock
Negative Input Clock Input. K is used to capture synchronous inputs being presented to the device and
to drive out data through Q
.
[x:0]
CQ
CQ
Echo Clock Synchronous Echo Clock Outputs. This is a free running clock and is synchronized to the input clock
(K) of the QDR-II+. The timings for the echo clocks are shown in the Switching Characteristics on page 23.
Echo Clock Synchronous Echo Clock Outputs. This is a free running clock and is synchronized to the input clock
(K) of the QDR-II+.The timings for the echo clocks are shown in the Switching Characteristics on page 23.
Document Number: 001-05389 Rev. *F
Page 6 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Pin Definitions (continued)
Pin Name
IO
Pin Description
ZQ
Input
Output Impedance Matching Input. This input is used to tune the device outputs to the system data bus
impedance. CQ, CQ and Q output impedance are set to 0.2 x RQ, where RQ is a resistor connected
[x:0]
between ZQ and ground. Alternately, this pin can be connected directly to V
, which enables the
DDQ
minimum impedance mode. This pin cannot be connected directly to GND or left unconnected.
DOFF
Input
DLL Turn Off − Active LOW. Connecting this pin to ground turns off the DLL inside the device.The timings
in the DLL turned off operation are different from those listed in this data sheet. For normal operation, this
pin can be connected to a pull up through a 10 KΩ or less pull up resistor. The device behaves in QDR-I
mode when the DLL is turned off. In this mode, the device can be operated at a frequency of up to 167
MHz with QDR-I timing.
TDO
Output
Input
Input
Input
N/A
TDO for JTAG.
TCK
TCK Pin for JTAG.
TDI
TDI Pin for JTAG.
TMS
TMS Pin for JTAG.
NC
Not Connected to the Die. Can be tied to any voltage level.
Not Connected to the Die. Can be tied to any voltage level.
Not Connected to the Die. Can be tied to any voltage level.
Reference Voltage Input. Static input used to set the reference level for HSTL inputs and Outputs as
NC/144M
NC/288M
N/A
N/A
V
Input-
REF
Reference well as AC measurement points.
V
V
V
Power Supply Power Supply Inputs to the Core of the Device.
DD
Ground
Ground for the Device.
SS
Power Supply Power Supply Inputs for the Outputs of the Device.
DDQ
Document Number: 001-05389 Rev. *F
Page 7 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
seamless transition between devices without the insertion of wait
states in a depth expanded memory.
Functional Overview
The CY7C1541V18, CY7C1556V18, CY7C1543V18, and
CY7C1545V18 are synchronous pipelined burst SRAMs
equipped with a read port and a write port. The read port is
dedicated to read operations and the write port is dedicated to
write operations. Data flows into the SRAM through the write port
and out through the read port. These devices multiplex the
address inputs to minimize the number of address pins required.
By having separate read and write ports, the QDR-II+ completely
eliminates the need to “turn-around” the data bus and avoids any
possible data contention, thereby simplifying system design.
Each access consists of four 8-bit data transfers in the case of
CY7C1541V18, four 9-bit data transfers in the case of
CY7C1556V18, four 18-bit data transfers in the case of
CY7C1543V18, and four 36-bit data transfers in the case of
CY7C1545V18, in two clock cycles.
Write Operations
Write operations are initiated by asserting WPS active at the
rising edge of the positive input cock (K). On the following K clock
rise the data presented to D
lower 18-bit write data register, provided BWS
asserted active. On the subsequent rising edge of the negative
input clock (K) the information presented to D is also stored
is latched and stored into the
[17:0]
are both
[1:0]
[17:0]
into the write data register, provided BWS
are both asserted
[1:0]
active. This process continues for one more cycle until four 18-bit
words (a total of 72 bits) of data are stored in the SRAM. The 72
bits of data are then written into the memory array at the specified
location. Therefore, write accesses to the device cannot be
initiated on two consecutive K clock rises. The internal logic of
the device ignores the second write request. Write accesses can
be initiated on every other rising edge of the positive input clock
(K). Doing so pipelines the data flow such that 18 bits of data can
be transferred into the device on every rising edge of the input
clocks (K and K).
Accesses for both ports are initiated on the positive input clock
(K). All synchronous input and output timing are referenced from
the rising edge of the input clocks (K and K).
All synchronous data inputs (D
) pass through input registers
[x:0]
When deselected, the write port ignores all inputs after the
pending write operations have been completed.
controlled by the input clocks (K and K). All synchronous data
outputs (Q ) outputs pass through output registers controlled
[x:0]
by the rising edge of the input clocks (K and K) as well.
Byte Write Operations
All synchronous control (RPS, WPS, NWS , BWS
) inputs
[x:0]
[x:0]
Byte write operations are supported by the CY7C1543V18. A
write operation is initiated as described in the Write Operations
section. The bytes that are written are determined by BWS and
pass through input registers controlled by the rising edge of the
input clocks (K and K).
0
CY7C1543V18 is described in the following sections. The same
basic descriptions apply to CY7C1541V18, CY7C1556V18, and
CY7C1545V18.
BWS , which are sampled with each set of 18-bit data words.
1
Asserting the appropriate Byte Write Select input during the data
portion of a write latches the data being presented and writes it
into the device. Deasserting the Byte Write Select input during
the data portion of a write enables the data stored in the device
for that byte to remain unaltered. This feature can be used to
simplify read, modify, or write operations to a byte write
operation.
Read Operations
The CY7C1543V18 is organized internally as four arrays of 1M
x 18. Accesses are completed in a burst of four sequential 18-bit
data words. Read operations are initiated by asserting RPS
active at the rising edge of the positive input clock (K). The
address presented to address inputs are stored in the read
address register. Following the next two K clock rise, the corre-
sponding lowest order 18-bit word of data is driven onto the
Concurrent Transactions
The read and write ports on the CY7C1543V18 operate
completely independently of one another. As each port latches
the address inputs on different clock edges, the user can read or
write to any location, regardless of the transaction on the other
port. If the ports access the same location when a read follows a
write in successive clock cycles, the SRAM delivers the most
recent information associated with the specified address
location. This includes forwarding data from a write cycle that
was initiated on the previous K clock rise.
Q
using K as the output timing reference. On the subse-
[17:0]
quent rising edge of K, the next 18-bit data word is driven onto
the Q . This process continues until all four 18-bit data words
[17:0]
have been driven out onto Q
. The requested data is valid
[17:0]
0.45 ns from the rising edge of the input clock (K or K). To
maintain the internal logic, each read access must be allowed to
complete. Each read access consists of four 18-bit data words
and takes two clock cycles to complete. Therefore, read
accesses to the device cannot be initiated on two consecutive K
clock rises. The internal logic of the device ignores the second
read request. Read accesses can be initiated on every other K
clock rise. Doing so pipelines the data flow such that data is
transferred out of the device on every rising edge of the input
clocks (K and K).
Read access and write access must be scheduled such that one
transaction is initiated on any clock cycle. If both ports are
selected on the same K clock rise, the arbitration depends on the
previous state of the SRAM. If both ports are deselected, the
read port takes priority. If a read was initiated on the previous
cycle, the write port assumes priority (as read operations cannot
be initiated on consecutive cycles). If a write was initiated on the
previous cycle, the read port assumes priority (as write opera-
tions cannot be initiated on consecutive cycles). Therefore,
asserting both port selects active from a deselected state results
in alternating read or write operations being initiated, with the first
access being a read.
When the read port is deselected, the CY7C1543V18 first
completes the pending read transactions. Synchronous internal
circuitry automatically tri-states the outputs following the next
rising edge of the positive input clock (K). This enables for a
Document Number: 001-05389 Rev. *F
Page 8 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Depth Expansion
Valid Data Indicator (QVLD)
The CY7C1543V18 has a port select input for each port. This
enables for easy depth expansion. Both port selects are sampled
on the rising edge of the positive input clock only (K). Each port
select input can deselect the specified port. Deselecting a port
does not affect the other port. All pending transactions (read and
write) are completed before the device is deselected.
QVLD is provided on the QDR-II+ to simplify data capture on high
speed systems. The QVLD is generated by the QDR-II+ device
along with data output. This signal is also edge-aligned with the
echo clock and follows the timing of any data pin. This signal is
asserted half a cycle before valid data arrives.
DLL
Programmable Impedance
These chips use a Delay Lock Loop (DLL) that is designed to
function between 120 MHz and the specified maximum clock
frequency. The DLL may be disabled by applying ground to the
DOFF pin. When the DLL is turned off, the device behaves in
QDR-I mode (with 1.0 cycle latency and a longer access time).
For more information, refer to the application note, “DLL Consid-
erations in QDRII/DDRII/QDRII+/DDRII+”. The DLL can also be
reset by slowing or stopping the input clocks K and K for a
minimum of 30ns. However, it is not necessary to reset the DLL
to lock to the desired frequency. During Power up, when the
DOFF is tied HIGH, the DLL is locked after 2048 cycles of stable
clock.
An external resistor, RQ, must be connected between the ZQ pin
on the SRAM and V to allow the SRAM to adjust its output
SS
driver impedance. The value of RQ must be 5X the value of the
intended line impedance driven by the SRAM, the allowable
range of RQ to guarantee impedance matching with a tolerance
of ±15% is between 175Ω and 350Ω, with V
= 1.5V. The
DDQ
output impedance is adjusted every 1024 cycles upon power up
to account for drifts in supply voltage and temperature.
Echo Clocks
Echo clocks are provided on the QDR-II+ to simplify data capture
on high-speed systems. Two echo clocks are generated by the
QDR-II+. CQ is referenced with respect to K and CQ is refer-
enced with respect to K. These are free-running clocks and are
synchronized to the input clock of the QDR-II+. The timing for the
Application Example
Figure 1 shows four QDR-II+ used in an application.
Figure 1. Application Example
RQ = 250ohms
RQ = 250ohms
ZQ
CQ/CQ
Q
ZQ
CQ/CQ
Q
Vt
SRAM #1
BWS
SRAM #4
D
A
D
A
R
K
RPS WPS
K
K
K
BWS
RPS WPS
DATA IN
DATA OUT
Address
R
R
Vt
Vt
RPS
BUS MASTER
WPS
BWS
(CPU or ASIC)
CLKIN/CLKIN
Source K
Source K
R = 50ohms, Vt = V
/2
DDQ
Document Number: 001-05389 Rev. *F
Page 9 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
The truth table for CY7C1541V18, CY7C1556V18, CY7C1543V18, and CY7C1545V18 follows.
Truth Table
Operation
K
RPS WPS
DQ
DQ
DQ
DQ
Write Cycle:
L-H
H
L
D(A) at K(t + 1) ↑ D(A + 1) at K(t +1) ↑ D(A + 2) at K(t + 2) ↑ D(A + 3) at K(t + 2) ↑
Load address on the rising
edge of K; input write data
on two consecutive K and
K rising edges.
Read Cycle:
(2.0 cycle Latency)
Load address on the rising
edge of K; wait two cycles;
read data on two consec-
utive K and K rising edges.
L-H
L-H
L
X
Q(A) at K(t + 2) ↑ Q(A + 1) at K(t + 2) ↑ Q(A + 2) at K(t + 3) ↑ Q(A + 3) at K(t + 3) ↑
NOP: No Operation
H
H
X
D = X
Q = High-Z
D = X
Q = High-Z
D = X
Q = High-Z
D = X
Q = High-Z
Standby: Clock Stopped Stopped X
Previous State
Previous State
Previous State
Previous State
The write cycle description table for CY7C1541V18 and CY7C1543V18 follows.
Write Cycle Descriptions
BWS / BWS /
0
1
K
Comments
K
NWS
NWS
1
0
L
L
L
L–H
–
During the data portion of a write sequence:
CY7C1541V18 − both nibbles (D
) are written into the device,
[7:0]
CY7C1543V18 − both bytes (D
) are written into the device.
[17:0]
L
–
L–H
–
L-H During the data portion of a write sequence:
CY7C1541V18 − both nibbles (D
) are written into the device,
) are written into the device.
[7:0]
CY7C1543V18 − both bytes (D
[17:0]
L
H
H
L
–
During the data portion of a write sequence:
CY7C1541V18 − only the lower nibble (D
) is written into the device, D
remains unaltered.
remains unaltered.
[3:0]
[7:4]
CY7C1543V18 − only the lower byte (D
) is written into the device, D
[8:0]
[17:9]
L
L–H During the data portion of a write sequence:
CY7C1541V18 − only the lower nibble (D
) is written into the device, D
remains unaltered.
remains unaltered.
[3:0]
[7:4]
CY7C1543V18 − only the lower byte (D
) is written into the device, D
[8:0]
[17:9]
H
H
L–H
–
–
During the data portion of a write sequence:
CY7C1541V18 − only the upper nibble (D
) is written into the device, D
) is written into the device, D
remains unaltered.
[3:0]
[7:4]
CY7C1543V18 − only the upper byte (D
remains unaltered.
[17:9]
[8:0]
L
L–H During the data portion of a write sequence:
CY7C1541V18 − only the upper nibble (D
) is written into the device, D
) is written into the device, D
remains unaltered.
remains unaltered.
[7:4]
[3:0]
[8:0]
CY7C1543V18 − only the upper byte (D
[17:9]
H
H
H
H
L–H
–
–
No data is written into the devices during this portion of a write operation.
L–H No data is written into the devices during this portion of a write operation.
Notes
3. X = “Don't Care,” H = Logic HIGH, L = Logic LOW, ↑represents rising edge.
4. Device powers up deselected with the outputs in a tri-state condition.
5. “A” represents address location latched by the devices when transaction was initiated. A + 1, A + 2, and A + 3 represents the address sequence in the burst.
6. “t” represents the cycle at which a read/write operation is started. t + 1, t + 2, and t + 3 are the first, second and third clock cycles respectively succeeding the “t” clock cycle.
7. Data inputs are registered at K and K rising edges. Data outputs are delivered on K and K rising edges, also.
8. It is recommended that K = K = HIGH when clock is stopped. This is not essential, but permits most rapid restart by overcoming transmission line charging symmetrically.
9. If this signal was LOW to initiate the previous cycle, this signal becomes a “Don’t Care” for this operation.
10. This signal was HIGH on previous K clock rise. Initiating consecutive read or write operations on consecutive K clock rises is not permitted. The device ignores the
second read or write request.
11. Is based on a write cycle was initiated per the The write cycle description table for CY7C1541V18 and CY7C1543V18 follows.
table. NWS , NWS , BWS , BWS ,
0
1
0
1
BWS , and BWS can be altered on different portions of a write cycle, as long as the setup and hold requirements are achieved.
2
3
Document Number: 001-05389 Rev. *F
Page 10 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
The write cycle description table for CY7C1556V18 follows.
Write Cycle Descriptions
BWS
K
L–H
–
K
0
L
L
–
During the Data portion of a write sequence, the single byte (D
) is written into the device.
) is written into the device.
[8:0]
L–H During the Data portion of a write sequence, the single byte (D
[8:0]
H
H
L–H
–
–
No data is written into the device during this portion of a write operation.
L–H No data is written into the device during this portion of a write operation.
The write cycle description table for CY7C1545V18 follows.
Write Cycle Descriptions
BWS
BWS
BWS
BWS
3
K
K
Comments
0
1
2
L
L
L
L
L–H
–
During the Data portion of a write sequence, all four bytes (D
the device.
) are written into
) are written into
[35:0]
L
L
L
H
H
L
L
H
H
H
H
L
L
H
H
H
H
H
H
L
–
L–H
–
L–H During the Data portion of a write sequence, all four bytes (D
the device.
[35:0]
–
During the Data portion of a write sequence, only the lower byte (D
) is written
) is written
[8:0]
into the device. D
remains unaltered.
[35:9]
L
L–H During the Data portion of a write sequence, only the lower byte (D
into the device. D remains unaltered.
[8:0]
[35:9]
H
H
H
H
H
H
L–H
–
–
During the Data portion of a write sequence, only the byte (D
) is written into
[17:9]
the device. D
and D
remains unaltered.
[8:0]
[35:18]
L
L–H During the Data portion of a write sequence, only the byte (D
the device. D and D remains unaltered.
) is written into
[17:9]
[8:0]
[35:18]
H
H
H
H
L–H
–
–
During the Data portion of a write sequence, only the byte (D
) is written into
) is written into
) is written into
) is written into
[26:18]
[26:18]
[35:27]
[35:27]
the device. D
and D
remains unaltered.
[17:0]
[35:27]
L
L–H During the Data portion of a write sequence, only the byte (D
the device. D and D remains unaltered.
[17:0]
[35:27]
H
H
L–H
–
–
During the Data portion of a write sequence, only the byte (D
the device. D remains unaltered.
[26:0]
L
L–H During the Data portion of a write sequence, only the byte (D
the device. D remains unaltered.
[26:0]
H
H
H
H
H
H
H
H
L–H
–
–
No data is written into the device during this portion of a write operation.
L–H No data is written into the device during this portion of a write operation.
Document Number: 001-05389 Rev. *F
Page 11 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Instruction Register
IEEE 1149.1 Serial Boundary Scan (JTAG)
Three-bit instructions can be serially loaded into the instruction
register. This register is loaded when it is placed between the TDI
page 15. Upon power up, the instruction register is loaded with
the IDCODE instruction. It is also loaded with the IDCODE
instruction if the controller is placed in a reset state, as described
in the previous section.
These SRAMs incorporate a serial boundary scan Test Access
Port (TAP) in the FBGA package. This part is fully compliant with
IEEE Standard #1149.1-2001. The TAP operates using JEDEC
standard 1.8V IO logic levels.
Disabling the JTAG Feature
It is possible to operate the SRAM without using the JTAG
feature. To disable the TAP controller, TCK must be tied LOW
When the TAP controller is in the Capture-IR state, the two least
significant bits are loaded with a binary “01” pattern to allow for
fault isolation of the board level serial test path.
(V ) to prevent clocking of the device. TDI and TMS are inter-
SS
nally pulled up and may be unconnected. They may alternatively
be connected to V through a pull up resistor. TDO must be left
unconnected. Upon power up, the device comes up in a reset
state, which does not interfere with the operation of the device.
Bypass Register
DD
To save time when serially shifting data through registers, it is
sometimes advantageous to skip certain chips. The bypass
register is a single-bit register that can be placed between TDI
and TDO pins. This enables shifting of data through the SRAM
with minimal delay. The bypass register is set LOW (V ) when
the BYPASS instruction is executed.
Test Access Port—Test Clock
The test clock is used only with the TAP controller. All inputs are
captured on the rising edge of TCK. All outputs are driven from
the falling edge of TCK.
SS
Boundary Scan Register
Test Mode Select (TMS)
The boundary scan register is connected to all of the input and
output pins on the SRAM. Several No Connect (NC) pins are also
included in the scan register to reserve pins for higher density
devices.
The TMS input is used to give commands to the TAP controller
and is sampled on the rising edge of TCK. This pin may be left
unconnected if the TAP is not used. The pin is pulled up inter-
nally, resulting in a logic HIGH level.
The boundary scan register is loaded with the contents of the
RAM input and output ring when the TAP controller is in the
Capture-DR state and is then placed between the TDI and TDO
pins when the controller is moved to the Shift-DR state. The
EXTEST, SAMPLE/PRELOAD, and SAMPLE Z instructions can
be used to capture the contents of the input and output ring.
Test Data-In (TDI)
The TDI pin is used to serially input information into the registers
and can be connected to the input of any of the registers. The
register between TDI and TDO is chosen by the instruction that
is loaded into the TAP instruction register. For information on
bits are connected. Each bit corresponds to one of the bumps on
the SRAM package. The MSB of the register is connected to TDI,
and the LSB is connected to TDO.
loading the instruction register, see the The state diagram for the
on page 14. TDI is internally pulled up
and can be unconnected if the TAP is unused in an application.
TDI is connected to the most significant bit (MSB) on any
register.
Identification (ID) Register
Test Data-Out (TDO)
The ID register is loaded with a vendor-specific, 32-bit code
during the Capture-DR state when the IDCODE command is
loaded in the instruction register. The IDCODE is hardwired into
the SRAM and can be shifted out when the TAP controller is in
the Shift-DR state. The ID register has a vendor code and other
The TDO output pin is used to serially clock data out from the
registers. The output is active, depending upon the current state
The output changes on the falling edge of TCK. TDO is
connected to the least significant bit (LSB) of any register.
Performing a TAP Reset
TAP Instruction Set
A Reset is performed by forcing TMS HIGH (V ) for five rising
DD
Eight different instructions are possible with the three-bit
instruction register. All combinations are listed in the Instruction
RESERVED and must not be used. The other five instructions
are described in this section in detail.
edges of TCK. This Reset does not affect the operation of the
SRAM and can be performed while the SRAM is operating. At
power up, the TAP is reset internally to ensure that TDO comes
up in a high-Z state.
TAP Registers
Instructions are loaded into the TAP controller during the Shift-IR
state when the instruction register is placed between TDI and
TDO. During this state, instructions are shifted through the
instruction register through the TDI and TDO pins. To execute
the instruction after it is shifted in, the TAP controller must be
moved into the Update-IR state.
Registers are connected between the TDI and TDO pins to scan
the data in and out of the SRAM test circuitry. Only one register
can be selected at a time through the instruction registers. Data
is serially loaded into the TDI pin on the rising edge of TCK. Data
is output on the TDO pin on the falling edge of TCK.
IDCODE
The IDCODE instruction loads a vendor-specific, 32-bit code into
the instruction register. It also places the instruction register
Document Number: 001-05389 Rev. *F
Page 12 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
between the TDI and TDO pins and shifts the IDCODE out of the
device when the TAP controller enters the Shift-DR state. The
IDCODE instruction is loaded into the instruction register at
power up or whenever the TAP controller is supplied a
Test-Logic-Reset state.
The shifting of data for the SAMPLE and PRELOAD phases can
occur concurrently when required, that is, the data captured is
shifted out, the preloaded data can be shifted in.
BYPASS
When the BYPASS instruction is loaded in the instruction register
and the TAP is placed in a Shift-DR state, the bypass register is
placed between the TDI and TDO pins. The advantage of the
BYPASS instruction is that it shortens the boundary scan path
when multiple devices are connected together on a board.
SAMPLE Z
The SAMPLE Z instruction connects the boundary scan register
between the TDI and TDO pins when the TAP controller is in a
Shift-DR state. The SAMPLE Z command puts the output bus
into a High-Z state until the next command is supplied during the
Update-IR state.
EXTEST
The EXTEST instruction drives the preloaded data out through
the system output pins. This instruction also connects the
boundary scan register for serial access between the TDI and
TDO in the Shift-DR controller state.
SAMPLE/PRELOAD
SAMPLE/PRELOAD is a 1149.1 mandatory instruction. When
the SAMPLE/PRELOAD instructions are loaded into the
instruction register and the TAP controller is in the Capture-DR
state, a snapshot of data on the input and output pins is captured
in the boundary scan register.
EXTEST OUTPUT BUS TRI-STATE
IEEE Standard 1149.1 mandates that the TAP controller be able
to put the output bus into a tri-state mode.
The user must be aware that the TAP controller clock can only
operate at a frequency up to 20 MHz, while the SRAM clock
operates more than an order of magnitude faster. Because there
is a large difference in the clock frequencies, it is possible that
during the Capture-DR state, an input or output undergoes a
transition. The TAP may then try to capture a signal while in
transition (metastable state). This does not harm the device, but
there is no guarantee as to the value that is captured.
Repeatable results may not be possible.
The boundary scan register has a special bit located at bit #108.
When this scan cell, called the “extest output bus tri-state”, is
latched into the preload register during the Update-DR state in
the TAP controller, it directly controls the state of the output
(Q-bus) pins, when the EXTEST is entered as the current
instruction. When HIGH, it enables the output buffers to drive the
output bus. When LOW, this bit places the output bus into a
High-Z condition.
To guarantee that the boundary scan register captures the
correct value of a signal, the SRAM signal must be stabilized
long enough to meet the TAP controller's capture setup plus hold
times (t and t ). The SRAM clock input might not be captured
correctly if there is no way in a design to stop (or slow) the clock
during a SAMPLE/PRELOAD instruction. If this is an issue, it is
still possible to capture all other signals and simply ignore the
value of the CK and CK captured in the boundary scan register.
This bit can be set by entering the SAMPLE/PRELOAD or
EXTEST command, and then shifting the desired bit into that cell,
during the Shift-DR state. During Update-DR, the value loaded
into that shift-register cell latches into the preload register. When
the EXTEST instruction is entered, this bit directly controls the
output Q-bus pins. Note that this bit is preset HIGH to enable the
output when the device is powered up, and also when the TAP
controller is in the Test-Logic-Reset state.
CS
CH
After the data is captured, it is possible to shift out the data by
putting the TAP into the Shift-DR state. This places the boundary
scan register between the TDI and TDO pins.
Reserved
These instructions are not implemented but are reserved for
future use. Do not use these instructions.
PRELOAD places an initial data pattern at the latched parallel
outputs of the boundary scan register cells before the selection
of another boundary scan test operation.
Document Number: 001-05389 Rev. *F
Page 13 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
The state diagram for the TAP controller follows.
TAP Controller State Diagram
TEST-LOGIC
1
RESET
0
1
1
1
SELECT
TEST-LOGIC/
SELECT
0
IR-SCAN
IDLE
DR-SCAN
0
0
1
1
CAPTURE-DR
0
CAPTURE-IR
0
0
0
SHIFT-DR
1
SHIFT-IR
1
1
0
1
EXIT1-DR
0
EXIT1-IR
0
0
PAUSE-DR
1
PAUSE-IR
1
0
0
EXIT2-DR
1
EXIT2-IR
1
UPDATE-IR
UPDATE-DR
1
1
0
0
Note
12. The 0/1 next to each state represents the value at TMS at the rising edge of TCK.
Document Number: 001-05389 Rev. *F
Page 14 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
TAP Controller Block Diagram
0
Bypass Register
2
1
0
Selection
TDI
Selection
Circuitry
TDO
Instruction Register
Circuitry
31 30 29
.
.
2
1
0
Identification Register
108
.
.
.
.
2
1
0
Boundary Scan Register
TCK
TMS
TAP Controller
TAP Electrical Characteristics
Over the Operating Range
Parameter
Description
Output HIGH Voltage
Test Conditions
= −2.0 mA
Min
1.4
1.6
Max
Unit
V
V
V
V
V
V
I
I
I
I
I
V
V
OH1
OH2
OL1
OL2
IH
OH
OH
OL
OL
Output HIGH Voltage
Output LOW Voltage
Output LOW Voltage
Input HIGH Voltage
= −100 μA
= 2.0 mA
0.4
0.2
V
= 100 μA
V
0.65V
V
+ 0.3
V
DD
DD
Input LOW Voltage
–0.3
–5
0.35V
5
V
IL
DD
Input and Output Load Current
GND ≤ V ≤ V
DD
μA
X
I
Notes
13. These characteristics pertain to the TAP inputs (TMS, TCK, TDI and TDO). Parallel load levels are specified in the Electrical Characteristics Table.
14. Overshoot: V (AC) < V + 0.35V (Pulse width less than t /2).
/2), Undershoot: V (AC) > −0.3V (Pulse width less than t
IH
DDQ
CYC
IL
CYC
15. All Voltage referenced to Ground.
Document Number: 001-05389 Rev. *F
Page 15 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
TAP AC Switching Characteristics
Over the Operating Range
Parameter
Description
Min
Max
Unit
ns
t
t
t
t
TCK Clock Cycle Time
TCK Clock Frequency
TCK Clock HIGH
50
TCYC
TF
20
MHz
ns
20
20
TH
TCK Clock LOW
ns
TL
Setup Times
t
t
t
TMS Setup to TCK Clock Rise
TDI Setup to TCK Clock Rise
Capture Setup to TCK Rise
5
5
5
ns
ns
ns
TMSS
TDIS
CS
Hold Times
t
t
t
TMS Hold after TCK Clock Rise
TDI Hold after Clock Rise
5
5
5
ns
ns
ns
TMSH
TDIH
Capture Hold after Clock Rise
CH
Output Times
t
t
TCK Clock LOW to TDO Valid
TCK Clock LOW to TDO Invalid
10
ns
ns
TDOV
TDOX
0
TAP Timing and Test Conditions
Figure 2 shows the TAP timing and test conditions.
Figure 2. TAP Timing and Test Conditions
0.9V
ALL INPUT PULSES
1.8V
50Ω
0.9V
TDO
0V
Z = 50
Ω
0
C = 20 pF
L
tTL
tTH
GND
(a)
Test Clock
TCK
tTCYC
tTMSH
tTMSS
Test Mode Select
TMS
tTDIS
tTDIH
Test Data In
TDI
Test Data Out
TDO
tTDOV
tTDOX
Notes
16. t and t refer to the setup and hold time requirements of latching data from the boundary scan register.
CS
CH
17. Test conditions are specified using the load in TAP AC Test Conditions. t /t = 1 ns.
R
F
Document Number: 001-05389 Rev. *F
Page 16 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Identification Register Definitions
Value
Instruction Field
Description
CY7C1541V18
CY7C1556V18
000
CY7C1543V18
000
CY7C1545V18
Revision Number
(31:29)
000
000
Version number.
Cypress Device ID 11010010101000100 11010010101001100 11010010101010100 11010010101100100 Defines the type of
(28:12)
SRAM.
Cypress JEDEC ID
(11:1)
00000110100
1
00000110100
1
00000110100
1
00000110100
1
Allows unique
identification of
SRAM vendor.
ID Register
Presence (0)
Indicates the
presence of an ID
register.
Scan Register Sizes
Register Name
Bit Size
Instruction
Bypass
3
1
ID
32
109
Boundary Scan
Instruction Codes
Instruction
EXTEST
Code
000
Description
Captures the input and output ring contents.
IDCODE
001
Loads the ID register with the vendor ID code and places the register between TDI and TDO.
This operation does not affect SRAM operation.
SAMPLE Z
010
Captures the input and output contents. Places the boundary scan register between TDI and
TDO. Forces all SRAM output drivers to a High-Z state.
RESERVED
011
100
Do Not Use: This instruction is reserved for future use.
SAMPLE/PRELOAD
Captures the input and output ring contents. Places the boundary scan register between TDI
and TDO. Does not affect the SRAM operation.
RESERVED
RESERVED
BYPASS
101
110
111
Do Not Use: This instruction is reserved for future use.
Do Not Use: This instruction is reserved for future use.
Places the bypass register between TDI and TDO. This operation does not affect SRAM
operation.
Document Number: 001-05389 Rev. *F
Page 17 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Boundary Scan Order
Bit #
0
Bump ID
6R
Bit #
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
Bump ID
10G
9G
Bit #
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
Bump ID
6A
5B
5A
4A
5C
4B
3A
2A
1A
2B
3B
1C
1B
3D
3C
1D
2C
3E
2D
2E
1E
2F
Bit #
84
Bump ID
1J
1
6P
85
2J
2
6N
11F
11G
9F
86
3K
3
7P
87
3J
4
7N
88
2K
5
7R
10F
11E
10E
10D
9E
89
1K
6
8R
90
2L
7
8P
91
3L
8
9R
92
1M
1L
9
11P
10P
10N
9P
93
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
10C
11D
9C
94
3N
95
3M
1N
96
10M
11N
9M
9D
97
2M
3P
11B
11C
9B
98
99
2N
9N
100
101
102
103
104
105
106
107
108
2P
11L
11M
9L
10B
11A
10A
9A
1P
3R
4R
10L
11K
10K
9J
4P
8B
5P
7C
3F
5N
6C
1G
1F
5R
9K
8A
Internal
10J
11J
11H
7A
3G
2G
1H
7B
6B
Document Number: 001-05389 Rev. *F
Page 18 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
DLL Constraints
Power Up Sequence in QDR-II+ SRAM
■ DLL uses K clock as its synchronizing input. The input must
have low phase jitter, which is specified as t
QDR-II+ SRAMs must be powered up and initialized in a
predefined manner to prevent undefined operations. During
Power Up, when the DOFF is tied HIGH, the DLL gets locked
after 2048 cycles of stable clock.
.
KC Var
■ The DLL functions at frequencies down to 120 MHz.
■ If the input clock is unstable and the DLL is enabled, then the
DLL may lock onto an incorrect frequency, causing unstable
SRAM behavior. To avoid this, provide 2048 cycles stable clock
to relock to the desired clock frequency.
Power Up Sequence
■ Apply power with DOFF tied HIGH (All other inputs can be
HIGH or LOW)
❐ Apply V before V
DD
DDQ
❐ Apply V
before V
or at the same time as V
DDQ
REF REF
■ Provide stable power and clock (K, K) for 2048 cycles to lock
the DLL.
Figure 3. Power Up Waveforms
K
K
Start Normal
Operation
Unstable Clock
> 2048 Stable Clock
Clock Start (Clock Starts after V /V
DD DDQ
is Stable)
V
/V
+
V
/V Stable (< 0.1V DC per 50 ns)
DD DDQ
DD DDQ
Fix HIGH (tie to V
DDQ
)
DOFF
Document Number: 001-05389 Rev. *F
Page 19 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Current into Outputs (LOW) ........................................ 20 mA
Static Discharge Voltage (MIL-STD-883, M. 3015)... >2001V
Latch-up Current .................................................... >200 mA
Maximum Ratings
Exceeding maximum ratings may impair the useful life of the
device. These user guidelines are not tested.
Storage Temperature ................................. –65°C to +150°C
Ambient Temperature with Power Applied.. –55°C to +125°C
Operating Range
Ambient
DD
V
DDQ
Supply Voltage on V Relative to GND........–0.5V to +2.9V
Range
Commercial
Industrial
Temperature (T )
V
DD
A
Supply Voltage on V
Relative to GND.......–0.5V to +V
0°C to +70°C
1.8 ± 0.1V
1.4V to
DDQ
DD
V
DD
DC Applied to Outputs in High-Z ........ –0.5V to V
+ 0.3V
–40°C to +85°C
DDQ
DC Input Voltage
.............................. –0.5V to V + 0.3V
DD
Electrical Characteristics
DC Electrical Characteristics
Over the Operating Range
Parameter
Description
Power Supply Voltage
IO Supply Voltage
Test Conditions
Min
1.7
1.4
Typ
Max
Unit
V
1.8
1.5
1.9
V
V
DD
V
V
V
V
V
V
V
I
V
DD
DDQ
OH
Output HIGH Voltage
Output LOW Voltage
Output HIGH Voltage
Output LOW Voltage
Note 19
Note 20
V
V
/2 – 0.12
/2 – 0.12
– 0.2
V
V
/2 + 0.12
/2 + 0.12
V
DDQ
DDQ
DDQ
V
OL
DDQ
I
I
= −0.1 mA, Nominal Impedance
V
V
V
OH(LOW)
OL(LOW)
IH
OH
OL
DDQ
DDQ
= 0.1 mA, Nominal Impedance
V
0.2
V
SS
Input HIGH Voltage
Input LOW Voltage
V
+ 0.1
V
+ 0.15
V
REF
DDQ
–0.15
V
– 0.1
V
IL
REF
Input Leakage Current
Output Leakage Current
Input Reference Voltage
GND ≤ V ≤ V
−2
−2
2
μA
μA
V
X
I
DDQ
I
GND ≤ V ≤ V
Output Disabled
2
OZ
I
DDQ,
V
Typical Value = 0.75V
0.68
0.75
0.95
1300
1300
1300
1370
1200
1200
1200
1230
1100
1100
1100
1140
REF
I
V
Operating Supply
V
= Max,
= 0 mA,
375 MHz
333 MHz
300 MHz
x8
x9
mA
DD
DD
DD
I
OUT
f = f
= 1/t
MAX
CYC
x18
x36
x8
mA
mA
x9
x18
x36
x8
x9
x18
x36
Notes
18. Power up: Assumes a linear ramp from 0V to V (min) within 200 ms. During this time V < V and V
< V .
DD
DD
IH
DD
DDQ
19. Output are impedance controlled. I = −(V
/2)/(RQ/5) for values of 175 Ω <= RQ <= 350 Ω.
OH
DDQ
20. Output are impedance controlled. I = (V
/2)/(RQ/5) for values of 175 Ω <= RQ <= 350 Ω.
OL
DDQ
21. V
(min) = 0.68V or 0.46V
, whichever is larger, V
(max) = 0.95V or 0.54V
, whichever is smaller.
DDQ
REF
DDQ
REF
22. The operation current is calculated with 50% read cycle and 50% write cycle.
Document Number: 001-05389 Rev. *F
Page 20 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Electrical Characteristics (continued)
DC Electrical Characteristics
[15]
Over the Operating Range
Parameter
Description
Test Conditions
, 375 MHz
DD
Min
Typ
Max
525
525
525
410
500
500
500
395
450
450
450
385
Unit
I
Automatic Power down
Current
Max V
x8
x9
mA
SB1
Both Ports Deselected,
V
≥ V or V ≤ V
IN
IH
= 1/t
IN
IL
f = f
Static
, Inputs
x18
x36
x8
MAX
CYC
333 MHz
300 MHz
mA
mA
x9
x18
x36
x8
x9
x18
x36
AC Electrical Characteristics
Over the Operating Range
Parameter
Description
Input HIGH Voltage
Input LOW Voltage
Test Conditions
Min
+ 0.2
Typ
–
Max
Unit
V
V
V
V
+ 0.24
DDQ
IH
IL
REF
V
–0.24
–
V
– 0.2
V
REF
Capacitance
Tested initially and after any design or process change that may affect these parameters.
Parameter
Description
Input Capacitance
Test Conditions
Max
Unit
C
T = 25°C, f = 1 MHz, V = 1.8V, V = 1.5V
DDQ
5
6
7
pF
pF
pF
IN
A
DD
C
Clock Input Capacitance
Output Capacitance
CLK
O
C
Document Number: 001-05389 Rev. *F
Page 21 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Thermal Resistance
Tested initially and after any design or process change that may affect these parameters.
165 FBGA
Package
Parameter
Description
Test Conditions
Unit
Θ
Thermal Resistance
(Junction to Ambient)
Test conditions follow standard test methods and
procedures for measuring thermal impedance, in
accordance with EIA/JESD51.
11.82
°C/W
JA
Θ
Thermal Resistance
(Junction to Case)
2.33
°C/W
JC
Figure 4. AC Test Loads and Waveforms
V
REF = 0.75V
0.75V
VREF
VREF
0.75V
R = 50Ω
OUTPUT
ALL INPUT PULSES
1.25V
Z = 50Ω
0
OUTPUT
Device
Under
Test
R = 50Ω
L
0.75V
Device
Under
0.25V
5 pF
VREF = 0.75V
Slew Rate = 2 V/ns
ZQ
Test
ZQ
RQ =
RQ =
250Ω
250Ω
INCLUDING
JIG AND
SCOPE
(a)
(b)
Note
23. Unless otherwise noted, test conditions assume signal transition time of 2V/ns, timing reference levels of 0.75V, Vref = 0.75V, RQ = 250Ω, V
= 1.5V, input pulse
DDQ
levels of 0.25V to 1.25V, and output loading of the specified I /I and load capacitance shown in (a) of AC Test Loads and Waveforms.
OL OH
Document Number: 001-05389 Rev. *F
Page 22 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Switching Characteristics
Over the Operating Range
375 MHz
333 MHz
300 MHz
CY
Consortium
Description
Unit
Parameter Parameter
Min Max Min Max Min Max
t
t
t
t
t
V
(Typical) to the First Access
1
1
1
ms
POWER
CYC
KH
DD
t
t
t
t
K Clock Cycle Time
2.66 8.40 3.0 8.40 3.3 8.40 ns
KHKH
KHKL
KLKH
KHKH
Input Clock (K/K) HIGH
Input Clock (K/K) LOW
0.4
0.4
–
–
–
0.4
0.4
0.4
0.4
–
–
–
t
t
CYC
KL
CYC
K Clock Rise to K Clock Rise (rising edge to rising edge)
1.13
1.28
–
1.40
ns
KHKH
Setup Times
t
t
t
t
t
t
Address Setup to K Clock Rise
0.4
0.4
–
–
–
0.4
0.4
–
–
–
0.4
0.4
–
–
–
ns
ns
ns
SA
AVKH
IVKH
IVKH
Control Setup to K Clock Rise (RPS, WPS)
SC
Double Data Rate Control Setup to Clock (K/K) Rise
0.28
0.28
0.28
SCDDR
(BWS , BWS BWS , BWS )
0
1,
2
3
t
t
D Setup to Clock (K/K) Rise
[X:0]
0.28
–
0.28
–
0.28
–
ns
SD
DVKH
Hold Times
t
t
t
t
t
t
Address Hold after K Clock Rise
0.4
0.4
–
–
–
0.4
0.4
–
–
–
0.4
0.4
–
–
–
ns
ns
ns
HA
KHAX
KHIX
KHIX
Control Hold after K Clock Rise (RPS, WPS)
HC
Double Data Rate Control Hold after Clock (K/K) Rise
0.28
0.28
0.28
HCDDR
(BWS , BWS BWS , BWS )
0
1,
2
3
t
t
D Hold after Clock (K/K) Rise
[X:0]
0.28
–
0.28
–
0.28
–
ns
HD
KHDX
Output Times
t
t
t
t
K/K Clock Rise to Data Valid
–
0.45
–
–
0.45
–
–
0.45 ns
ns
CO
CHQV
CHQX
Data Output Hold after Output K/K Clock Rise
(Active to Active)
–0.45
–0.45
–0.45
–
DOH
t
t
t
t
t
t
t
t
t
t
t
t
K/K Clock Rise to Echo Clock Valid
Echo Clock Hold after K/K Clock Rise
Echo Clock High to Data Valid
–
0.45
–
–
0.45
–
–
0.45 ns
CCQO
CQOH
CQD
CHCQV
CHCQX
CQHQV
CQHQX
CQHCQL
CQHCQH
–0.45
–0.45
–0.45
–
0.2
–
ns
ns
ns
ns
ns
0.2
–
0.2
–
Echo Clock High to Data Invalid
–0.2
0.88
0.88
–0.2
1.03
1.03
–0.2
1.15
1.15
CQDOH
CQH
Output Clock (CQ/CQ) HIGH
–
–
–
[26]
CQ Clock Rise to CQ Clock Rise
–
–
–
CQHCQH
(rising edge to rising edge)
t
t
t
t
t
t
Clock (K/K) Rise to High-Z (Active to High-Z)
–
0.45
–
–
0.45
–
–
0.45 ns
ns
CHZ
CLZ
CHQZ
Clock (K/K) Rise to Low-Z
–0.45
–0.45
–0.45
–
CHQX1
CQHQVLD
Echo Clock High to QVLD Valid
–0.20 0.20 –0.20 0.20 –0.20 0.20 ns
QVLD
DLL Timing
t
t
t
t
t
t
Clock Phase Jitter
DLL Lock Time (K)
–
0.20
–
–
0.20
–
–
0.20 ns
Cycles
ns
KC Var
KC Var
2048
30
2048
30
2048
30
–
KC lock
KC Reset
KC lock
KC Reset
K Static to DLL Reset
Notes
24. When a part with a maximum frequency above 300MHz is operating at a lower clock frequency, it requires the input timings of the frequency range in which it is being
operated and outputs data with the output timings of that frequency range.
25. This part has a voltage regulator internally; t
be initiated.
is the time that the power needs to be supplied above V minimum initially before a read or write operation can
POWER
DD
26. These parameters are extrapolated from the input timing parameters (t
-250ps, where 250ps is the internal jitter. An input jitter of 200ps(t
) is already included
KHKH
KCVAR
in the t
). These parameters are only guaranteed by design and are not tested in production.
KHKH
27. t
, t
, are specified with a load capacitance of 5 pF as in part (b) of “AC Test Loads and Waveforms” on page 22. Transition is measured ± 100 mV from steady-state
CHZ CLZ
voltage.
28. At any given voltage and temperature t
is less than t
and t
less than t
.
CO
CHZ
CLZ
CHZ
29. t
spec is applicable for both rising and falling edges of QVLD signal.
QVLD
30. Hold to >V or <V .
IH
IL
Document Number: 001-05389 Rev. *F
Page 23 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Switching Waveforms
Read/Write/Deselect Sequence
Figure 5. Waveform for 2.0 Cycle Read Latency
NOP
1
READ
2
WRITE
3
READ
4
WRITE
5
NOP
6
7
8
K
t
t
CYC
t
t
KH
KL
KHKH
K
RPS
t
t
SC HC
t
t
SC
HC
WPS
A
A0
A1
A2
A3
t
t
HD
t
t
HD
SA HA
t
SD
t
SD
D10
D11
D12
D13
D30
D31
D32
D33
D
t
QVLD
t
QVLD
QVLD
t
DOH
t
t
CQDOH
CO
t
t
CHZ
t
CLZ
CQD
Q
Q22
Q01
Q02
Q23
Q00
t
Q03 Q20 Q21
(Read Latency = 2.0 Cycles)
CCQO
CQOH
CQ
CQ
CCQO
t
t
t
CQHCQH
CQH
CQOH
DON’T CARE
UNDEFINED
Notes
31. Q00 refers to output from address A0. Q01 refers to output from the next internal burst address following A0, that is, A0+1.
32. Outputs are disabled (High-Z) one clock cycle after a NOP.
33. In this example, if address A2 = A1, then data Q20 = D10, Q21 = D11, Q22 = D12, and Q23 = D13. Write data is forwarded immediately as read results. This note
applies to the whole diagram.
Document Number: 001-05389 Rev. *F
Page 24 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Ordering Information
Not all of the speed, package and temperature ranges are available. Please contact your local sales representative or
Speed
(MHz)
Package
Diagram
Operating
Range
Ordering Code
Package Type
375 CY7C1541V18-375BZC
CY7C1556V18-375BZC
CY7C1543V18-375BZC
CY7C1545V18-375BZC
CY7C1541V18-375BZXC
CY7C1556V18-375BZXC
CY7C1543V18-375BZXC
CY7C1545V18-375BZXC
CY7C1541V18-375BZI
CY7C1556V18-375BZI
CY7C1543V18-375BZI
CY7C1545V18-375BZI
CY7C1541V18-375BZXI
CY7C1556V18-375BZXI
CY7C1543V18-375BZXI
CY7C1545V18-375BZXI
333 CY7C1541V18-333BZC
CY7C1556V18-333BZC
CY7C1543V18-333BZC
CY7C1545V18-333BZC
CY7C1541V18-333BZXC
CY7C1556V18-333BZXC
CY7C1543V18-333BZXC
CY7C1545V18-333BZXC
CY7C1541V18-333BZI
CY7C1556V18-333BZI
CY7C1543V18-333BZI
CY7C1545V18-333BZI
CY7C1541V18-333BZXI
CY7C1556V18-333BZXI
CY7C1543V18-333BZXI
CY7C1545V18-333BZXI
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm)
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm) Pb-Free
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm)
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm) Pb-Free
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm)
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm) Pb-Free
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm)
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm) Pb-Free
Commercial
Industrial
Commercial
Industrial
Document Number: 001-05389 Rev. *F
Page 25 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Ordering Information (continued)
Not all of the speed, package and temperature ranges are available. Please contact your local sales representative or
Speed
(MHz)
Package
Diagram
Operating
Range
Ordering Code
Package Type
300 CY7C1541V18-300BZC
CY7C1556V18-300BZC
CY7C1543V18-300BZC
CY7C1545V18-300BZC
CY7C1541V18-300BZXC
CY7C1556V18-300BZXC
CY7C1543V18-300BZXC
CY7C1545V18-300BZXC
CY7C1541V18-300BZI
CY7C1556V18-300BZI
CY7C1543V18-300BZI
CY7C1545V18-300BZI
CY7C1541V18-300BZXI
CY7C1556V18-300BZXI
CY7C1543V18-300BZXI
CY7C1545V18-300BZXI
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm)
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm) Pb-Free
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm)
51-85195 165-Ball Fine Pitch Ball Grid Array (15 x 17 x 1.4 mm) Pb-Free
Commercial
Industrial
Document Number: 001-05389 Rev. *F
Page 26 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Package Diagram
Figure 6. 165-ball FBGA (15 x 17 x 1.4 mm), 51-85195
"/44/- 6)%7
4/0 6)%7
0). ꢀ #/2.%2
ꢃꢂꢃꢄ - #
ꢃꢂꢇꢄ - # ! "
ꢌꢃꢂꢀꢈ
0). ꢀ #/2.%2
ꢃꢂꢄꢃ
ꢅꢀꢆꢄ8
ꢍꢃꢂꢃꢆ
ꢀ
ꢇ
ꢉ
ꢈ
ꢄ
ꢆ
ꢁ
ꢊ
ꢋ
ꢀꢃ
ꢀꢀ
ꢀꢀ ꢀꢃ
ꢋ
ꢊ
ꢁ
ꢆ
ꢄ
ꢈ
ꢉ
ꢇ
ꢀ
!
"
!
"
#
$
#
$
%
%
&
&
'
'
(
*
(
*
+
+
,
,
-
-
.
0
2
.
0
2
!
ꢀꢂꢃꢃ
ꢄꢂꢃꢃ
ꢀꢃꢂꢃꢃ
"
ꢀꢄꢂꢃꢃ¼ꢃꢂꢀꢃ
ꢃꢂꢀꢄꢅꢈ8
./4%3 ꢎ
3/,$%2 0!$ 490% ꢎ./. 3/,$%2 -!3+ $%&).%$ ꢅ.3-$
0!#+!'% 7%)'(4 ꢎꢃꢂꢆꢄG
*%$%# 2%&%2%.#% ꢎ-/ꢍꢇꢀꢆ ꢏ $%3)'. ꢈꢂꢆ#
0!#+!'% #/$% ꢎ""ꢃ!$
3%!4).' 0,!.%
#
51-85195-*A
Document Number: 001-05389 Rev. *F
Page 27 of 28
CY7C1541V18, CY7C1556V18
CY7C1543V18, CY7C1545V18
Document History Page
Document Title: CY7C1541V18/CY7C1556V18/CY7C1543V18/CY7C1545V18, 72-Mbit QDR™-II+ SRAM 4-Word Burst Archi-
tecture (2.0 Cycle Read Latency)
Document Number: 001-05389
ISSUE
DATE
ORIG. OF
CHANGE
REV. ECN NO.
DESCRIPTION OF CHANGE
**
403090 See ECN
425252 See ECN
VEE
VEE
New Data Sheet
*A
Updated the DLL Section
Fixed typos in the DC and AC parameter section
Updated the switching waveform
Updated the Power up sequence
Added additional parameters in the AC timing
*B
*C
437000 See ECN
461934 See ECN
IGS
ECN for Show on web
NXR
Moved the Selection Guide table from page# 3 to page# 1
Modified Application Diagram
Changed t and t from 40 ns to 20 ns, changed t
, t
, t , t
, t
, t
TH
TL
TMSS TDIS CS TMSH TDIH CH
from 10 ns to 5 ns and changed t
Characteristics table
from 20 ns to 10 ns in TAP AC Switching
TDOV
Modified Power Up waveform
Included Maximum ratings for Supply Voltage on V
Relative to GND
DDQ
Changed the Maximum Ratings for DC Input Voltage from V
to V
DDQ
DD
Changed the Pin Definition of I from Input Load current to Input Leakage current on
X
page#18
*D
497567 See ECN
NXR
Changed the V
operating voltage to 1.4V to V in the Features section, in
DDQ DD
Operating Range table and in the DC Electrical Characteristics table
Added foot note in page# 1
Changed the Maximum rating of Ambient Temperature with Power Applied from –10°C
to +85°C to –55°C to +125°C
Changed V (Max) spec from 0.85V to 0.95V in the DC Electrical Characteristics
REF
table and in the note below the table
Updated footnote #21 to specify Overshoot and Undershoot Spec
Updated I and I values
DD
SB
Updated Θ and Θ values
JA
JC
Removed x9 part and its related information
Updated footnote #25
*E
*F
1351243 See ECN VKN/FSU Converted from preliminary to final
Added x8 and x9 parts
Changed t
max spec to 8.4 ns for all speed bins
CYC
Updated footnote# 23
Updated Ordering Information table
2181046 See ECN VKN/AESA Added footnote# 22 related to I
DD
© Cypress Semiconductor Corporation, 2005-2008. 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: 001-05389 Rev. *F
Revised March 06, 2008
Page 28 of 28
QDR RAMs and Quad Data Rate RAMs comprise a new family of products developed by Cypress, IDT, NEC, Renesas, and Samsung. All product and company names mentioned in this document
are the trademarks of their respective holders.
|