CY7C1518KV18, CY7C1520KV18 72-Mbit DDR II SRAM Two-Word Burst Architecture Datasheet.pdf

CY7C1518KV18
CY7C1520KV18
72-Mbit DDR-II SRAM Two-Word
Burst Architecture
72-Mbit DDR-II SRAM Two-Word Burst Architecture
Features
Configurations
■
72-Mbit density (4M × 18, 2M × 36)
CY7C1518KV18 – 4M × 18
■
333 MHz clock for high bandwidth
CY7C1520KV18 – 2M × 36
■
Two-word burst for reducing address bus frequency
Functional Description
■
Double data rate (DDR) interfaces (data transferred at
666 MHz) at 333 MHz
■
Two input clocks (K and K) for precise DDR timing
❐ SRAM uses rising edges only
■
Two input clocks for output data (C and C) to minimize clock
skew and flight time mismatches
■
Echo clocks (CQ and CQ) simplify data capture in high speed
systems
■
Synchronous internally self-timed writes
■
DDR II operates with 1.5 cycle read latency when DOFF is
asserted HIGH
■
Operates similar to DDR-I device with 1 cycle read latency
when DOFF is asserted LOW
■
1.8 V core power supply with HSTL inputs and outputs
■
Variable drive HSTL output buffers
■
Expanded HSTL output voltage (1.4 V–VDD)
❐ Supports both 1.5 V and 1.8 V IO supply
■
Available in 165-ball fine pitch ball grid array (FBGA) package
(13 × 15 × 1.4 mm)
■
Offered in both Pb-free and non Pb-free packages
■
JTAG 1149.1 compatible Test Access Port
■
Phase-locked loop (PLL) for accurate data placement
The CY7C1518KV18, and CY7C1520KV18 are 1.8 V
synchronous pipelined SRAM equipped with DDR II architecture.
The DDR II consists of an SRAM core with advanced
synchronous peripheral circuitry and a 1-bit burst counter.
Addresses for read and write are latched on alternate rising
edges of the input (K) clock. Write data is registered on the rising
edges of both K and K. Read data is driven on the rising edges
of C and C if provided, or on the rising edge of K and K if C/C are
not provided. On CY7C1518KV18 and CY7C1520KV18, the
burst counter takes in the least significant bit of the external
address and bursts two 18-bit words in the case of
CY7C1518KV18 and two 36-bit words in the case of
CY7C1520KV18 sequentially into or out of the device.
Asynchronous inputs include an output impedance matching
input (ZQ). Synchronous data outputs (Q, sharing the same
physical pins as the data inputs D) are tightly matched to the two
output echo clocks CQ/CQ, eliminating the need for separately
capturing data from each individual DDR SRAM in the system
design. Output data clocks (C/C) enable maximum system
clocking and data synchronization flexibility.
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 C or C (or K or K in a single clock
domain) input clocks. Writes are conducted with on-chip
synchronous self-timed write circuitry.
For a complete list of related documentation, click here.
Selection Guide
Description
333 MHz
300 MHz
250 MHz
Unit
333
300
250
MHz
× 18
520
490
430
mA
× 36
640
600
530
Maximum Operating Frequency
Maximum Operating Current
Cypress Semiconductor Corporation
Document Number: 001-00437 Rev. *U
•
198 Champion Court
•
San Jose, CA 95134-1709
•
408-943-2600
Revised February 4, 2016
CY7C1518KV18
CY7C1520KV18
Logic Block Diagram – CY7C1518KV18
Burst
Logic
22
Write
Reg
21
A(21:1)
CLK
Gen.
K
DOFF
2M x 18 Array
K
Write
Reg
2M x 18 Array
LD
Address
Register
Write Add. Decode
A(21:0)
Read Add. Decode
A0
18
Output
Logic
Control
R/W
C
Read Data Reg.
36
VREF
Control
Logic
R/W
BWS[1:0]
C
18
Reg.
18
CQ
Reg. 18
CQ
18
18
Reg.
DQ[17:0]
Logic Block Diagram – CY7C1520KV18
Burst
Logic
21
Write
Reg
20
A(20:1)
K
CLK
Gen.
DOFF
VREF
R/W
BWS[3:0]
1M x 36 Array
K
Address
Register
Write
Reg
1M x 36 Array
LD
Write Add. Decode
A(20:0)
Read Add. Decode
A0
36
Output
Logic
Control
R/W
C
Read Data Reg.
72
Control
Logic
Document Number: 001-00437 Rev. *U
36
36
C
Reg.
Reg.
CQ
Reg. 36
36
CQ
36
DQ[35:0]
Page 2 of 32
CY7C1518KV18
CY7C1520KV18
Contents
Pin Configurations ........................................................... 4
Pin Definitions .................................................................. 5
Functional Overview ........................................................ 6
Read Operations ......................................................... 6
Write Operations ......................................................... 6
Byte Write Operations ................................................. 7
Single Clock Mode ...................................................... 7
DDR Operation ............................................................ 7
Depth Expansion ......................................................... 7
Programmable Impedance .......................................... 7
Echo Clocks ................................................................ 7
PLL .............................................................................. 7
Application Example ........................................................ 8
Truth Table ........................................................................ 9
Burst Address Table ........................................................ 9
Write Cycle Descriptions ............................................... 10
Write Cycle Descriptions ............................................... 11
IEEE 1149.1 Serial Boundary Scan (JTAG) .................. 12
Disabling the JTAG Feature ...................................... 12
Test Access Port ....................................................... 12
Performing a TAP Reset ........................................... 12
TAP Registers ........................................................... 12
TAP Instruction Set ................................................... 12
TAP Controller State Diagram ....................................... 14
TAP Controller Block Diagram ...................................... 15
TAP Electrical Characteristics ...................................... 15
TAP AC Switching Characteristics ............................... 16
TAP Timing and Test Conditions .................................. 17
Identification Register Definitions ................................ 18
Scan Register Sizes ....................................................... 18
Document Number: 001-00437 Rev. *U
Instruction Codes ........................................................... 18
Boundary Scan Order .................................................... 19
Power Up Sequence in DDR II SRAM ........................... 20
Power Up Sequence ................................................. 20
PLL Constraints ......................................................... 20
Maximum Ratings ........................................................... 21
Operating Range ............................................................. 21
Neutron Soft Error Immunity ......................................... 21
Electrical Characteristics ............................................... 21
DC Electrical Characteristics ..................................... 21
AC Electrical Characteristics ..................................... 23
Capacitance .................................................................... 23
Thermal Resistance ........................................................ 23
AC Test Loads and Waveforms ..................................... 23
Switching Characteristics .............................................. 24
Switching Waveforms .................................................... 26
Read/Write/Deselect Sequence ................................ 26
Ordering Information ...................................................... 27
Ordering Code Definitions ......................................... 27
Package Diagram ............................................................ 28
Acronyms ........................................................................ 29
Document Conventions ................................................. 29
Units of Measure ....................................................... 29
Document History Page ................................................. 30
Sales, Solutions, and Legal Information ...................... 32
Worldwide Sales and Design Support ....................... 32
Products .................................................................... 32
PSoC® Solutions ...................................................... 32
Cypress Developer Community ................................. 32
Technical Support ..................................................... 32
Page 3 of 32
CY7C1518KV18
CY7C1520KV18
Pin Configurations
The pin configurations for CY7C1518KV18, and CY7C1520KV18 follow. [1]
Figure 1. 165-ball FBGA (13 × 15 × 1.4 mm) pinout
CY7C1518KV18 (4M × 18)
1
2
3
4
5
6
7
8
9
10
11
A
CQ
A
A
R/W
BWS1
K
NC/144M
LD
A
A
CQ
B
NC
DQ9
NC
A
NC/288M
K
BWS0
A
NC
NC
DQ8
C
NC
NC
NC
VSS
A
A0
A
VSS
NC
DQ7
NC
D
NC
NC
DQ10
VSS
VSS
VSS
VSS
VSS
NC
NC
NC
E
NC
NC
DQ11
VDDQ
VSS
VSS
VSS
VDDQ
NC
NC
DQ6
F
NC
DQ12
NC
VDDQ
VDD
VSS
VDD
VDDQ
NC
NC
DQ5
G
NC
NC
DQ13
VDDQ
VDD
VSS
VDD
VDDQ
NC
NC
NC
H
DOFF
VREF
VDDQ
VDDQ
VDD
VSS
VDD
VDDQ
VDDQ
VREF
ZQ
J
NC
NC
NC
VDDQ
VDD
VSS
VDD
VDDQ
NC
DQ4
NC
K
NC
NC
DQ14
VDDQ
VDD
VSS
VDD
VDDQ
NC
NC
DQ3
L
NC
DQ15
NC
VDDQ
VSS
VSS
VSS
VDDQ
NC
NC
DQ2
M
NC
NC
NC
VSS
VSS
VSS
VSS
VSS
NC
DQ1
NC
N
NC
NC
DQ16
VSS
A
A
A
VSS
NC
NC
NC
P
NC
NC
DQ17
A
A
C
A
A
NC
NC
DQ0
R
TDO
TCK
A
A
A
C
A
A
A
TMS
TDI
9
10
11
CY7C1520KV18 (2M × 36)
1
2
3
4
A
CQ
B
NC
C
D
5
6
7
8
NC/144M
A
DQ27
DQ18
R/W
BWS2
K
BWS1
LD
A
A
CQ
A
BWS3
K
BWS0
A
NC
NC
DQ8
NC
NC
DQ28
VSS
A
A0
A
VSS
NC
DQ17
DQ7
NC
DQ29
DQ19
VSS
VSS
VSS
VSS
VSS
NC
NC
DQ16
E
NC
NC
DQ20
VDDQ
VSS
VSS
VSS
VDDQ
NC
DQ15
DQ6
F
NC
DQ30
DQ21
VDDQ
VDD
VSS
VDD
VDDQ
NC
NC
DQ5
G
NC
DQ31
DQ22
VDDQ
VDD
VSS
VDD
VDDQ
NC
NC
DQ14
H
DOFF
VREF
VDDQ
VDDQ
VDD
VSS
VDD
VDDQ
VDDQ
VREF
ZQ
J
NC
NC
DQ32
VDDQ
VDD
VSS
VDD
VDDQ
NC
DQ13
DQ4
K
NC
NC
DQ23
VDDQ
VDD
VSS
VDD
VDDQ
NC
DQ12
DQ3
L
NC
DQ33
DQ24
VDDQ
VSS
VSS
VSS
VDDQ
NC
NC
DQ2
M
NC
NC
DQ34
VSS
VSS
VSS
VSS
VSS
NC
DQ11
DQ1
N
NC
DQ35
DQ25
VSS
A
A
A
VSS
NC
NC
DQ10
P
NC
NC
DQ26
A
A
C
A
A
NC
DQ9
DQ0
R
TDO
TCK
A
A
A
C
A
A
A
TMS
TDI
Note
1. NC/144M and NC/288M are not connected to the die and can be tied to any voltage level.
Document Number: 001-00437 Rev. *U
Page 4 of 32
CY7C1518KV18
CY7C1520KV18
Pin Definitions
Pin Name
I/O
Pin Description
DQ[x:0]
Input Output- Data input output signals. Inputs are sampled on the rising edge of K and K clocks during valid write
Synchronous operations. These pins drive out the requested data when the read operation is active. Valid data is
driven out on the rising edge of both the C and C clocks during read operations or K and K when in single
clock mode. When read access is deselected, Q[x:0] are automatically tristated.
CY7C1518KV18  DQ[17:0]
CY7C1520KV18  DQ[35:0]
LD
InputSynchronous load. This input is brought LOW when a bus cycle sequence is defined. This definition
Synchronous includes address and read/write direction. All transactions operate on a burst of 2 data.
BWS0,
BWS1,
BWS2,
BWS3
InputByte Write Select 0, 1, 2, and 3  Active LOW. Sampled on the rising edge of the K and K clocks during
Synchronous write operations. Used to select which byte is written into the device during the current portion of the
write operations. Bytes not written remain unaltered.
CY7C1518KV18 BWS0 controls D[8:0] and BWS1 controls D[17:9].
CY7C1520KV18  BWS0 controls D[8:0], BWS1 controls D[17:9], BWS2 controls D[26:18] and BWS3
controls D[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, A0
InputAddress inputs. These address inputs are multiplexed for both read and write operations. Internally,
Synchronous the device is organized as 4M × 18 (2 arrays each of 2M × 18) for CY7C1518KV18, and 2M × 36 (2
arrays each of 1M × 36) for CY7C1520KV18.
CY7C1518KV18 – A0 is the input to the burst counter. These are incremented in a linear fashion
internally. 22 address inputs are needed to access the entire memory array.
CY7C1520KV18 – A0 is the input to the burst counter. These are incremented in a linear fashion
internally. 21 address inputs are needed to access the entire memory array. All the address inputs are
ignored when the appropriate port is deselected.
R/W
InputSynchronous read or write input. When LD is LOW, this input designates the access type (read when
Synchronous R/W is HIGH, write when R/W is LOW) for loaded address. R/W must meet the setup and hold times
around edge of K.
C
Input Clock
Positive input clock for output data. C is used in conjunction with C to clock out the read data from
the device. C and C can be used together to deskew the flight times of various devices on the board
back to the controller. See application example for further details.
C
Input Clock
Negative input clock for output data. C is used in conjunction with C to clock out the read data from
the device. C and C can be used together to deskew the flight times of various devices on the board
back to the controller. See application example for further details.
K
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[x:0] when in single clock mode. All accesses are initiated on the rising
edge of K.
K
Input Clock
Negative input clock input. K is used to capture synchronous data being presented to the device and
to drive out data through Q[x:0] when in single clock mode.
CQ
Output Clock CQ referenced with respect to C. This is a free running clock and is synchronized to the input clock
for output data (C) of the DDR II. In the single clock mode, CQ is generated with respect to K. The timing
for the echo clocks is shown in the AC Timing table.
CQ
Output Clock CQ referenced with respect to C. This is a free running clock and is synchronized to the input clock
for output data (C) of the DDR II. In the single clock mode, CQ is generated with respect to K. The timing
for the echo clocks is shown in the AC Timing table.
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[x:0] output impedance are set to 0.2 × RQ, where RQ is a resistor
connected between ZQ and ground. Alternatively, this pin can be connected directly to VDDQ, which
enables the minimum impedance mode. This pin cannot be connected directly to GND or left
unconnected.
Document Number: 001-00437 Rev. *U
Page 5 of 32
CY7C1518KV18
CY7C1520KV18
Pin Definitions (continued)
Pin Name
DOFF
I/O
Pin Description
Input
PLL turn off  Active LOW. Connecting this pin to ground turns off the PLL inside the device. The timing
in the PLL turned off operation differs from those listed in this data sheet. For normal operation, this pin
is connected to a pull up through a 10 k or less pull up resistor. The device behaves in DDR-I mode
when the PLL is turned off. In this mode, the device can be operated at a frequency of up to 167 MHz
with DDR-I timing.
TDO
Output
TCK
Input
Test data out (TDO) pin for JTAG
Test clock (TCK) pin for JTAG
TDI
Input
Test data in (TDI) pin for JTAG
TMS
Input
Test mode select (TMS) pin for JTAG
NC
N/A
Not connected to the die. Can be tied to any voltage level.
NC/144M
Input
Not connected to the die. Can be tied to any voltage level.
NC/288M
Input
Not connected to the die. Can be tied to any voltage level.
VREF
VDD
VSS
VDDQ
InputReference
Reference voltage input. Static input used to set the reference level for HSTL inputs, outputs, and AC
measurement points.
Power Supply Power supply Inputs to the core of the device.
Ground
Ground for the device.
Power Supply Power supply inputs for the outputs of the device.
Functional Overview
The CY7C1518KV18, and CY7C1520KV18 are synchronous
pipelined Burst SRAMs equipped with a DDR interface, which
operates with a read latency of one and a half cycles when DOFF
pin is tied HIGH. When DOFF pin is set LOW or connected to
VSS the device behaves in DDR-I mode with a read latency of
one clock cycle.
Accesses are initiated on the rising edge of the positive input
clock (K). All synchronous input timing is referenced from the
rising edge of the input clocks (K and K) and all output timing is
referenced to the rising edge of the output clocks (C/C, or K/K
when in single clock mode).
All synchronous data inputs (D[x:0]) pass through input registers
controlled by the rising edge of the input clocks (K and K). All
synchronous data outputs (Q[x:0]) pass through output registers
controlled by the rising edge of the output clocks (C/C, or K/K
when in single clock mode).
All synchronous control (R/W, LD, BWS[0:X]) inputs pass through
input registers controlled by the rising edge of the input clock (K).
CY7C1518KV18 is described in the following sections. The
same basic descriptions apply to CY7C1520KV18.
Read Operations
The CY7C1518KV18 is organized internally as a two arrays of
2M × 18. Accesses are completed in a burst of 2 sequential 18-bit
data words. Read operations are initiated by asserting R/W
HIGH and LD LOW at the rising edge of the positive input clock
(K). The address presented to address inputs is stored in the
read address register and the least significant bit of the address
is presented to the burst counter. The burst counter increments
the address in a linear fashion. Following the next K clock rise,
the corresponding 18-bit word of data from this address location
is driven onto the Q[17:0] using C as the output timing reference.
Document Number: 001-00437 Rev. *U
On the subsequent rising edge of C the next 18-bit data word
from the address location generated by the burst counter is
driven onto the Q[17:0]. The requested data is valid 0.45 ns from
the rising edge of the output clock (C or C, or K and K when in
single clock mode, 250 MHz, and 300 MHz device). To maintain
the internal logic, each read access must be allowed to
complete. Read accesses can be initiated on every rising edge
of the positive input clock (K).
When read access is deselected, the CY7C1518KV18 first
completes the pending read transactions. Synchronous internal
circuitry automatically tristates the output following the next rising
edge of the positive output clock (C). This enables for a transition
between devices without the insertion of wait states in a depth
expanded memory.
Write Operations
Write operations are initiated by asserting R/W LOW and LD
LOW at the rising edge of the positive input clock (K). The
address presented to address inputs is stored in the write
address register and the least significant bit of the address is
presented to the burst counter. The burst counter increments the
address in a linear fashion. On the following K clock rise, the data
presented to D[17:0] is latched and stored into the 18-bit write
data register, provided BWS[1:0] are both asserted active. On the
subsequent rising edge of the Negative Input Clock (K) the
information presented to D[17:0] is also stored into the write data
register, provided BWS[1:0] are both asserted active. The 36 bits
of data are then written into the memory array at the specified
location. Write accesses can be initiated on every 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).
When the write access is deselected, the device ignores all
inputs after the pending write operations have been completed.
Page 6 of 32
CY7C1518KV18
CY7C1520KV18
Byte Write Operations
Byte write operations are supported by the CY7C1518KV18. A
write operation is initiated as described in the Write Operations
section. The bytes that are written are determined by BWS0 and
BWS1, which are sampled with each set of 18-bit data words.
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 is used to simplify
read, modify, or write operations to a byte write operation.
Single Clock Mode
The CY7C1518KV18 is used with a single clock that controls
both the input and output registers. In this mode, the device
recognizes only a single pair of input clocks (K and K) that control
both the input and output registers. This operation is identical to
the operation if the device had zero skew between the K/K and
C/C clocks. All timing parameters remain the same in this mode.
To use this mode of operation, the user must tie C and C HIGH
at power on. This function is a strap option and not alterable
during device operation.
DDR Operation
The CY7C1518KV18 enables high-performance operation
through high clock frequencies (achieved through pipelining) and
DDR mode of operation. The CY7C1518KV18 requires a single
No Operation (NOP) cycle during transition from a read to a write
cycle. At higher frequencies, some applications may require a
second NOP cycle to avoid contention.
If a read occurs after a write cycle, address and data for the write
are stored in registers. The write information must be stored
because the SRAM cannot perform the last word write to the
array without conflicting with the read. The data stays in this
register until the next write cycle occurs. On the first write cycle
after the read(s), the stored data from the earlier write is written
into the SRAM array. This is called a posted write.
If a read is performed on the same address on which a write is
performed in the previous cycle, the SRAM reads out the most
Document Number: 001-00437 Rev. *U
current data. The SRAM does this by bypassing the memory
array and reading the data from the registers.
Depth Expansion
Depth expansion requires replicating the LD control signal for
each bank. All other control signals can be common between
banks as appropriate.
Programmable Impedance
An external resistor, RQ, must be connected between the ZQ pin
on the SRAM and VSS to allow the SRAM to adjust its output
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 175  and 350 , with VDDQ = 1.5 V. The
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 DDR II to simplify data capture
on high speed systems. Two echo clocks are generated by the
DDR II. CQ is referenced with respect to C and CQ is referenced
with respect to C. These are free running clocks and are
synchronized to the output clock of the DDR II. In single clock
mode, CQ is generated with respect to K and CQ is generated
with respect to K. The timing for the echo clocks is shown in the
Switching Characteristics on page 24.
PLL
These chips use a PLL that is designed to function between
120 MHz and the specified maximum clock frequency. During
power up, when the DOFF is tied HIGH, the PLL is locked after
20 s of stable clock. The PLL can also be reset by slowing or
stopping the input clock K and K for a minimum of 30 ns.
However, it is not necessary to reset the PLL to lock to the
desired frequency. The PLL automatically locks 20 s after a
stable clock is presented. The PLL may be disabled by applying
ground to the DOFF pin. When the PLL is turned off, the device
behaves in DDR-I mode (with one cycle latency and a longer
access time).
Page 7 of 32
CY7C1518KV18
CY7C1520KV18
Application Example
Figure 2 shows two DDR II used in an application.
Figure 2. Application Example (Width Expansion)
SRAM#1
DQ[x:0]
A
ZQ
CQ/CQ
LD R/W BWS C C K K
RQ
SRAM#2
DQ[x:0]
A LD R/W
ZQ
CQ/CQ
RQ
BWS C C K K
DQ[2x:0]
ADDRESS
LD
R/W
BWS
CLKIN1/CLKIN1
CLKIN2/CLKIN2
SOURCE K
SOURCE K
DELAYED K
DELAYED K
FPGA / ASIC
Document Number: 001-00437 Rev. *U
Page 8 of 32
CY7C1518KV18
CY7C1520KV18
Truth Table
The truth table for the CY7C1518KV18, and CY7C1520KV18 follows. [2, 3, 4, 5, 6, 7]
Operation
K
LD
R/W
Write cycle:
Load address; wait one cycle;
input write data on consecutive K and K rising edges.
L–H
L
L
D(A1) at K(t + 1)  D(A2) at K(t + 1) 
Read cycle:
Load address; wait one and a half cycle;
read data on consecutive C and C rising edges.
L–H
L
H
Q(A1) at C(t + 1) Q(A2) at C(t + 2) 
NOP: No operation
L–H
H
X
High Z
High Z
Stopped
X
X
Previous State
Previous State
Standby: Clock stopped
DQ
DQ
Burst Address Table
(CY7C1518KV18, CY7C1520KV18)
First Address (External)
Second Address (Internal)
X..X0
X..X1
X..X1
X..X0
Notes
2. X = “Don’t Care,” H = Logic HIGH, L = Logic LOW, represents rising edge.
3. Device powers up deselected with the outputs in a tristate condition.
4. On CY7C1518KV18 and CY7C1520KV18, “A1” represents address location latched by the devices when transaction was initiated and “A2” represents the addresses
sequence in the burst.
5. “t” represents the cycle at which a read/write operation is started. t + 1 and t + 2 are the first and second clock cycles succeeding the “t” clock cycle.
6. Data inputs are registered at K and K rising edges. Data outputs are delivered on C and C rising edges, except when in single clock mode.
7. Ensure that when the clock is stopped K = K and C = C = HIGH. This is not essential, but permits most rapid restart by overcoming transmission line charging
symmetrically.
Document Number: 001-00437 Rev. *U
Page 9 of 32
CY7C1518KV18
CY7C1520KV18
Write Cycle Descriptions
The write cycle description table for CY7C1518KV18 follows. [8, 9]
BWS0
BWS1
K
K
L
L
L–H
–
L
L
–
L
H
L–H
L
H
–
H
L
L–H
H
L
–
H
H
L–H
H
H
–
Comments
During the data portion of a write sequence
CY7C1518KV18 both bytes (D[17:0]) are written into the device.
L–H During the data portion of a write sequence:
CY7C1518KV18 both bytes (D[17:0]) are written into the device.
–
During the data portion of a write sequence:
CY7C1518KV18 only the lower byte (D[8:0]) is written into the device, D[17:9] remains unaltered.
L–H During the data portion of a write sequence
CY7C1518KV18 only the lower byte (D[8:0]) is written into the device, D[17:9] remains unaltered.
–
During the data portion of a write sequence
CY7C1518KV18 only the upper byte (D[17:9]) is written into the device, D[8:0] remains unaltered.
L–H During the data portion of a write sequence
CY7C1518KV18 only the upper byte (D[17:9]) is written into the device, D[8:0] remains unaltered.
–
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
8. X = “Don’t Care,” H = Logic HIGH, L = Logic LOW, represents rising edge.
9. Is based on a write cycle that was initiated in accordance with the Truth Table on page 9. BWS0, BWS1, BWS2, and BWS3 can be altered on different portions of a
write cycle, as long as the setup and hold requirements are achieved.
Document Number: 001-00437 Rev. *U
Page 10 of 32
CY7C1518KV18
CY7C1520KV18
Write Cycle Descriptions
The write cycle description table for CY7C1520KV18 follows. [10, 11]
BWS0
BWS1
BWS2
BWS3
K
K
Comments
L
L
L
L
L–H
–
During the data portion of a write sequence, all four bytes (D[35:0]) are written into
the device.
L
L
L
L
–
L
H
H
H
L–H
L
H
H
H
–
H
L
H
H
L–H
H
L
H
H
–
H
H
L
H
L–H
H
H
L
H
–
H
H
H
L
L–H
H
H
H
L
–
H
H
H
H
L–H
H
H
H
H
–
L–H During the data portion of a write sequence, all four bytes (D[35:0]) are written into
the device.
–
During the data portion of a write sequence, only the lower byte (D[8:0]) is written
into the device. D[35:9] remains unaltered.
L–H During the data portion of a write sequence, only the lower byte (D[8:0]) is written
into the device. D[35:9] remains unaltered.
–
During the data portion of a write sequence, only the byte (D[17:9]) is written into the
device. D[8:0] and D[35:18] remains unaltered.
L–H During the data portion of a write sequence, only the byte (D[17:9]) is written into the
device. D[8:0] and D[35:18] remains unaltered.
–
During the data portion of a write sequence, only the byte (D[26:18]) is written into
the device. D[17:0] and D[35:27] remains unaltered.
L–H During the data portion of a write sequence, only the byte (D[26:18]) is written into
the device. D[17:0] and D[35:27] remains unaltered.
–
During the data portion of a write sequence, only the byte (D[35:27]) is written into
the device. D[26:0] remains unaltered.
L–H During the data portion of a write sequence, only the byte (D[35:27]) is written into
the device. D[26:0] remains unaltered.
–
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.
Notes
10. X = “Don’t Care,” H = Logic HIGH, L = Logic LOW, represents rising edge.
11. Is based on a write cycle that was initiated in accordance with the Truth Table on page 9. BWS0, BWS1, BWS2, and BWS3 can be altered on different portions of a
write cycle, as long as the setup and hold requirements are achieved.
Document Number: 001-00437 Rev. *U
Page 11 of 32
CY7C1518KV18
CY7C1520KV18
IEEE 1149.1 Serial Boundary Scan (JTAG)
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 1.8 V 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
(VSS) to prevent clocking of the device. TDI and TMS are
internally pulled up and may be unconnected. They may
alternatively be connected to VDD 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.
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.
Test Mode Select (TMS)
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
internally, resulting in a logic HIGH level.
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 about
loading the instruction register, see the TAP Controller State
Diagram 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.
Test Data-Out (TDO)
The TDO output pin is used to serially clock data out from the
registers. The output is active, depending upon the current state
of the TAP state machine (see Instruction Codes on page 18).
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
A Reset is performed by forcing TMS HIGH (VDD) for five rising
edges of TCK. This Reset does not affect the operation of the
SRAM and is performed when 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
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.
Document Number: 001-00437 Rev. *U
Instruction Register
Three-bit instructions are serially loaded into the instruction
register. This register is loaded when it is placed between the TDI
and TDO pins, as shown in TAP Controller Block Diagram on
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.
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.
Bypass Register
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 (VSS) when
the BYPASS instruction is executed.
Boundary Scan Register
The boundary scan register is connected to all 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 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 are
used to capture the contents of the input and output ring.
The Boundary Scan Order on page 19 shows the order in which
the 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.
Identification (ID) Register
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 is shifted out when the TAP controller is in the
Shift-DR state. The ID register has a vendor code and other
information described in Identification Register Definitions on
page 18.
TAP Instruction Set
Eight different instructions are possible with the three-bit
instruction register. All combinations are listed in Instruction
Codes on page 18. Three of these instructions are listed as
RESERVED and must not be used. The other five instructions
are described in this section in detail.
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.
Page 12 of 32
CY7C1518KV18
CY7C1520KV18
IDCODE
The IDCODE instruction loads a vendor-specific, 32-bit code into
the instruction register. It also places the instruction register
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.
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.
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.
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.
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 (tCS and tCH). 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.
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.
Document Number: 001-00437 Rev. *U
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.
The shifting of data for the SAMPLE and PRELOAD phases can
occur concurrently when required, that is, while 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.
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.
EXTEST OUTPUT BUS TRISTATE
IEEE Standard 1149.1 mandates that the TAP controller be able
to put the output bus into a tristate mode.
The boundary scan register has a special bit located at bit #108.
When this scan cell, called the “extest output bus tristate,” 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.
This bit is 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.
Reserved
These instructions are not implemented but are reserved for
future use. Do not use these instructions.
Page 13 of 32
CY7C1518KV18
CY7C1520KV18
TAP Controller State Diagram
The state diagram for the TAP controller follows. [12]
1
TEST-LOGIC
RESET
0
0
TEST-LOGIC/
IDLE
1
SELECT
DR-SCAN
1
1
SELECT
IR-SCAN
0
0
1
1
CAPTURE-DR
CAPTURE-IR
0
0
SHIFT-DR
0
SHIFT-IR
1
1
EXIT1-DR
1
EXIT1-IR
0
0
PAUSE-IR
1
0
1
EXIT2-DR
0
EXIT2-IR
1
1
UPDATE-IR
UPDATE-DR
1
1
0
PAUSE-DR
0
0
0
1
0
Note
12. The 0/1 next to each state represents the value at TMS at the rising edge of TCK.
Document Number: 001-00437 Rev. *U
Page 14 of 32
CY7C1518KV18
CY7C1520KV18
TAP Controller Block Diagram
0
Bypass Register
2
Selection
Circuitry
TDI
1
0
Selection
Circuitry
Instruction Register
31
30
29
.
.
2
1
0
1
0
TDO
Identification Register
108
.
.
.
.
2
Boundary Scan Register
TCK
TAP Controller
TMS
TAP Electrical Characteristics
Over the Operating Range
Parameter [13, 14, 15]
Description
Test Conditions
Min
Max
Unit
VOH1
Output HIGH voltage
IOH =2.0 mA
1.4
–
V
VOH2
Output HIGH voltage
IOH =100 A
1.6
–
V
VOL1
Output LOW voltage
IOL = 2.0 mA
–
0.4
V
VOL2
Output LOW voltage
IOL = 100 A
–
0.2
V
VIH
Input HIGH voltage
VIL
Input LOW voltage
IX
Input and output load current
0.65 × VDD VDD + 0.3
GND  VI  VDD
V
–0.3
0.35 × VDD
V
–5
5
A
Notes
13. These characteristics pertain to the TAP inputs (TMS, TCK, TDI and TDO). Parallel load levels are specified in Electrical Characteristics on page 21.
14. Overshoot: VIH(AC) < VDDQ + 0.85 V (Pulse width less than tCYC/2), Undershoot: VIL(AC) > 1.5 V (Pulse width less than tCYC/2).
15. All voltage referenced to Ground.
Document Number: 001-00437 Rev. *U
Page 15 of 32
CY7C1518KV18
CY7C1520KV18
TAP AC Switching Characteristics
Over the Operating Range
Parameter [16, 17]
Description
Min
Max
Unit
50
–
ns
tTCYC
TCK clock cycle time
tTF
TCK clock frequency
–
20
MHz
tTH
TCK clock HIGH
20
–
ns
tTL
TCK clock LOW
20
–
ns
tTMSS
TMS setup to TCK clock rise
5
–
ns
tTDIS
TDI setup to TCK clock rise
5
–
ns
tCS
Capture setup to TCK rise
5
–
ns
tTMSH
TMS hold after TCK clock rise
5
–
ns
tTDIH
TDI hold after clock rise
5
–
ns
tCH
Capture hold after clock rise
5
–
ns
tTDOV
TCK clock LOW to TDO valid
–
10
ns
tTDOX
TCK clock LOW to TDO invalid
0
–
ns
Setup Times
Hold Times
Output Times
Notes
16. tCS and tCH refer to the setup and hold time requirements of latching data from the boundary scan register.
17. Test conditions are specified using the load in TAP AC Test Conditions. tR/tF = 1 ns.
Document Number: 001-00437 Rev. *U
Page 16 of 32
CY7C1518KV18
CY7C1520KV18
TAP Timing and Test Conditions
Figure 3 shows the TAP timing and test conditions. [18]
Figure 3. TAP Timing and Test Conditions
0.9 V
ALL INPUT PULSES
1.8 V
0.9 V
50 
TDO
0V
Z0 = 50 
(a)
CL = 20 pF
tTH
GND
tTL
Test Clock
TCK
tTMSH
tTMSS
tTCYC
Test Mode Select
TMS
tTDIS
tTDIH
Test Data In
TDI
Test Data Out
TDO
tTDOV
tTDOX
Note
18. Test conditions are specified using the load in TAP AC Test Conditions. tR/tF = 1 ns.
Document Number: 001-00437 Rev. *U
Page 17 of 32
CY7C1518KV18
CY7C1520KV18
Identification Register Definitions
Value
Instruction Field
CY7C1518KV18
Revision number (31:29)
000
000
Cypress device ID (28:12)
11010100010010100
11010100010100100
Cypress JEDEC ID (11:1)
00000110100
00000110100
1
1
ID register presence (0)
Description
CY7C1520KV18
Version number.
Defines the type of SRAM.
Allows unique identification of SRAM
vendor.
Indicates the presence of an ID register.
Scan Register Sizes
Register Name
Bit Size
Instruction
3
Bypass
1
ID
32
Boundary Scan
109
Instruction Codes
Instruction
Code
Description
EXTEST
000
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
Do Not Use: This instruction is reserved for future use.
SAMPLE/PRELOAD
100
Captures the input and output ring contents. Places the boundary scan register between TDI
and TDO. Does not affect the SRAM operation.
RESERVED
101
Do Not Use: This instruction is reserved for future use.
RESERVED
110
Do Not Use: This instruction is reserved for future use.
BYPASS
111
Places the bypass register between TDI and TDO. This operation does not affect SRAM
operation.
Document Number: 001-00437 Rev. *U
Page 18 of 32
CY7C1518KV18
CY7C1520KV18
Boundary Scan Order
Bit #
Bump ID
Bit #
Bump ID
Bit #
Bump ID
Bit #
Bump ID
0
6R
28
10G
56
6A
84
1J
1
6P
29
9G
57
5B
85
2J
2
6N
30
11F
58
5A
86
3K
3
7P
31
11G
59
4A
87
3J
4
7N
32
9F
60
5C
88
2K
5
7R
33
10F
61
4B
89
1K
6
8R
34
11E
62
3A
90
2L
7
8P
35
10E
63
2A
91
3L
8
9R
36
10D
64
1A
92
1M
9
11P
37
9E
65
2B
93
1L
10
10P
38
10C
66
3B
94
3N
11
10N
39
11D
67
1C
95
3M
12
9P
40
9C
68
1B
96
1N
13
10M
41
9D
69
3D
97
2M
14
11N
42
11B
70
3C
98
3P
15
9M
43
11C
71
1D
99
2N
16
9N
44
9B
72
2C
100
2P
17
11L
45
10B
73
3E
101
1P
18
11M
46
11A
74
2D
102
3R
19
9L
47
10A
75
2E
103
4R
20
10L
48
9A
76
1E
104
4P
21
11K
49
8B
77
2F
105
5P
22
10K
50
7C
78
3F
106
5N
23
9J
51
6C
79
1G
107
5R
24
9K
52
8A
80
1F
108
Internal
25
10J
53
7A
81
3G
26
11J
54
7B
82
2G
27
11H
55
6B
83
1H
Document Number: 001-00437 Rev. *U
Page 19 of 32
CY7C1518KV18
CY7C1520KV18
Power Up Sequence in DDR II SRAM
PLL Constraints
DDR II SRAMs must be powered up and initialized in a
predefined manner to prevent undefined operations.
■
PLL uses K clock as its synchronizing input. The input must
have low phase jitter, which is specified as tKC Var.
■
The PLL functions at frequencies down to 120 MHz.
■
If the input clock is unstable and the PLL is enabled, then the
PLL may lock onto an incorrect frequency, causing unstable
SRAM behavior. To avoid this, provide 20 s of stable clock to
relock to the desired clock frequency.
Power Up Sequence
■
Apply power and drive DOFF either HIGH or LOW (All other
inputs can be HIGH or LOW).
❐ Apply VDD before VDDQ.
❐ Apply VDDQ before VREF or at the same time as VREF.
❐ Drive DOFF HIGH.
■
Provide stable DOFF (HIGH), power and clock (K, K) for 20 s
to lock the PLL.
~
~
Figure 4. Power Up Waveforms
K
K
~
~
Unstable Clock
> 20μs Stable clock
Start Normal
Operation
Clock Start (Clock Starts after V DD / V DDQ Stable)
VDD / VDDQ
DOFF
Document Number: 001-00437 Rev. *U
V DD / V DDQ Stable (< +/- 0.1V DC per 50ns )
Fix HIGH (or tie to VDDQ)
Page 20 of 32
CY7C1518KV18
CY7C1520KV18
Maximum Ratings
Operating Range
Exceeding maximum ratings may impair the useful life of the
device. These user guidelines are not tested.
Range
Storage temperature ................................ –65 °C to +150 °C
Commercial
Ambient temperature
with power applied ................................... –55 °C to +125 °C
Industrial
Ambient
Temperature (TA)
0 °C to +70 °C
VDD[20]
VDDQ[20]
1.8 ± 0.1 V 1.4 V to VDD
–40 °C to +85 °C
Supply voltage on VDD relative to GND .......–0.5 V to +2.9 V
Supply voltage on VDDQ relative to GND ...... –0.5 V to +VDD
DC applied to outputs in High Z ........–0.5 V to VDDQ + 0.3 V
Neutron Soft Error Immunity
DC input voltage [19] ........................... –0.5 V to VDD + 0.3 V
Current into outputs (LOW) ........................................ 20 mA
Static discharge voltage
(MIL-STD-883, M 3015) .......................................... >2001 V
Latch up current ..................................................... >200 mA
Test
Conditions Typ
Parameter
Description
Max*
Unit
LSBU
Logical
single-bit
upsets
25 °C
197
216
FIT/M
b
LMBU
Logical
multi-bit
upsets
25 °C
0
0.01 FIT/M
b
SEL
Single event
latch up
85 °C
0
0.1
FIT/D
ev
* No LMBU or SEL events occurred during testing; this column represents a
statistical 2, 95% confidence limit calculation. For more details refer to Application
Note AN54908 “Accelerated Neutron SER Testing and Calculation of Terrestrial
Failure Rates”
Electrical Characteristics
Over the Operating Range
DC Electrical Characteristics
Over the Operating Range
Parameter [21]
Description
VDD
Power supply voltage
Test Conditions
Min
Typ
Max
Unit
1.7
1.8
1.9
V
VDDQ
IO supply voltage
1.4
1.5
VDD
V
VOH
Output HIGH voltage
Note 22
VDDQ/2 – 0.12
–
VDDQ/2 + 0.12
V
VOL
Output LOW voltage
Note 23
VDDQ/2 – 0.12
–
VDDQ/2 + 0.12
V
VOH(LOW)
Output HIGH voltage
IOH =0.1 mA, Nominal impedance
VDDQ – 0.2
–
VDDQ
V
IOL = 0.1 mA, Nominal impedance
VOL(LOW)
Output LOW voltage
VSS
–
0.2
V
VIH
Input HIGH voltage
VREF + 0.1
–
VDDQ + 0.3
V
VIL
Input LOW voltage
–0.3
–
VREF – 0.1
V
IX
Input leakage current
GND  VI  VDDQ
5
–
5
A
IOZ
Output leakage current
GND  VI  VDDQ, Output disabled
VREF
Input reference voltage [24] Typical value = 0.75 V
5
–
5
A
0.68
0.75
0.95
V
Notes
19. Overshoot: VIH(AC) < VDDQ + 0.85 V (Pulse width less than tCYC/2), Undershoot: VIL(AC) > 1.5 V (Pulse width less than tCYC/2).
20. Power up: assumes a linear ramp from 0 V to VDD(min) within 200 ms. During this time VIH < VDD and VDDQ < VDD.
21. All voltage referenced to Ground.
22. Outputs are impedance controlled. IOH = –(VDDQ/2)/(RQ/5) for values of 175  < RQ < 350 .
23. Outputs are impedance controlled. IOL = (VDDQ/2)/(RQ/5) for values of 175  < RQ < 350 .
24. VREF(min) = 0.68 V or 0.46 VDDQ, whichever is larger, VREF(max) = 0.95 V or 0.54 VDDQ, whichever is smaller.
Document Number: 001-00437 Rev. *U
Page 21 of 32
CY7C1518KV18
CY7C1520KV18
Electrical Characteristics (continued)
Over the Operating Range
DC Electrical Characteristics (continued)
Over the Operating Range
Parameter [21]
IDD[25]
ISB1
Description
VDD operating supply
Automatic power down
current
Test Conditions
Min
Typ
Max
Unit
VDD = Max, IOUT = 0 mA, 333 MHz (× 18)
f = fMAX = 1/tCYC
(× 36)
–
–
520
mA
–
–
640
300 MHz (× 18)
–
–
490
(× 36)
–
–
600
250 MHz (× 18)
–
–
430
(× 36)
–
–
530
Max VDD,
333 MHz (× 18)
Both Ports Deselected,
(× 36)
VIN  VIH or VIN  VIL
f = fMAX = 1/tCYC,
300 MHz (× 18)
Inputs Static
(× 36)
–
–
290
–
–
290
–
–
280
–
–
280
250 MHz (× 18)
–
–
270
(× 36)
–
–
270
mA
mA
mA
mA
mA
Note
25. The operation current is calculated with 50% read cycle and 50% write cycle.
Document Number: 001-00437 Rev. *U
Page 22 of 32
CY7C1518KV18
CY7C1520KV18
AC Electrical Characteristics
Over the Operating Range
Parameter [26]
Description
Test Conditions
Min
Typ
Max
Unit
VIH
Input HIGH voltage
VREF + 0.2
–
–
V
VIL
Input LOW voltage
–
–
VREF – 0.2
V
Max
Unit
4
pF
4
pF
Capacitance
Parameter [27]
Description
CIN
Input capacitance
CO
Output capacitance
Test Conditions
TA = 25 C, f = 1 MHz, VDD = 1.8 V, VDDQ = 1.5 V
Thermal Resistance
Parameter [27]
JA (0 m/s)
Description
Thermal resistance
(junction to ambient)
JA (1 m/s)
165-ball FBGA Unit
Package
Test Conditions
Socketed on a 170 × 220 × 2.35 mm, eight-layer printed
circuit board
JA (3 m/s)
14.43
°C/W
13.40
°C/W
12.66
°C/W
JB
Thermal resistance
(junction to board)
11.38
°C/W
JC
Thermal resistance
(junction to case)
3.30
°C/W
AC Test Loads and Waveforms
Figure 5. AC Test Loads and Waveforms
VREF = 0.75 V
VREF
0.75 V
VREF
OUTPUT
Z0 = 50 
Device
Under
Test
ZQ
RL = 50 
R = 50 
ALL INPUT PULSES
1.25 V
0.75 V
OUTPUT
Device
Under
VREF = 0.75 V Test ZQ
RQ =
250 
(a)
0.75 V
INCLUDING
JIG AND
SCOPE
5 pF
[28]
0.25 V
Slew Rate = 2 V/ns
RQ =
250 
(b)
Notes
26. Overshoot: VIH(AC) < VDDQ + 0.85 V (Pulse width less than tCYC/2), Undershoot: VIL(AC) > 1.5 V (Pulse width less than tCYC/2).
27. Tested initially and after any design or process change that may affect these parameters.
28. Unless otherwise noted, test conditions assume signal transition time of 2 V/ns, timing reference levels of 0.75 V, VREF = 0.75 V, RQ = 250, VDDQ = 1.5 V, input pulse
levels of 0.25 V to 1.25 V, and output loading of the specified IOL/IOH and load capacitance shown in (a) of Figure 5.
Document Number: 001-00437 Rev. *U
Page 23 of 32
CY7C1518KV18
CY7C1520KV18
Switching Characteristics
Over the Operating Range
Parameters [29, 30]
Cypress Consortium
Parameter Parameter
333 MHz
Description
VDD(typical) to the first access [31]
tPOWER
300 MHz
250 MHz
Unit
Min
Max
Min
Max
Min
Max
1
–
1
–
1
–
ms
tCYC
tKHKH
K clock and C clock cycle time
3.0
8.4
3.3
8.4
4.0
8.4
ns
tKH
tKHKL
Input clock (K/K and C/C) HIGH
1.20
–
1.32
–
1.6
–
ns
tKL
tKLKH
Input clock (K/K and C/C) LOW
1.20
–
1.32
–
1.6
–
ns
tKHKH
tKHKH
K clock rise to K clock rise and C
to C rise (rising edge to rising
edge)
1.35
–
1.49
–
1.8
–
ns
tKHCH
tKHCH
K/K clock rise t o C/C clock rise
(rising edge to rising edge)
0.0
1.30
0.0
1.45
0.0
1.8
ns
Setup Times
tSA
tAVKH
Address setup to K clock rise
0.4
–
0.4
–
0.5
–
ns
tSC
tIVKH
Control setup to K clock rise (LD,
R/W)
0.4
–
0.4
–
0.5
–
ns
tSCDDR
tIVKH
Double data rate control setup to
clock (K/K) Rise (BWS0, BWS1,
BWS2, BWS3)
0.3
–
0.3
–
0.35
–
ns
tSD
tDVKH
D[X:0] setup to clock (K/K) rise
0.3
–
0.3
–
0.35
–
ns
tHA
tKHAX
Address hold after K clock rise
0.4
–
0.4
–
0.5
–
ns
tHC
tKHIX
Control hold after K clock rise
(LD, R/W)
0.4
–
0.4
–
0.5
–
ns
tHCDDR
tKHIX
Double data rate control hold
after clock (K/K) rise (BWS0,
BWS1, BWS2, BWS3)
0.3
–
0.3
–
0.35
–
ns
tHD
tKHDX
D[X:0] hold after clock (K/K) rise
0.3
–
0.3
–
0.35
–
ns
Hold Times
Notes
29. Unless otherwise noted, test conditions assume signal transition time of 2 V/ns, timing reference levels of 0.75 V, VREF = 0.75 V, RQ = 250, VDDQ = 1.5 V, input pulse
levels of 0.25 V to 1.25 V, and output loading of the specified IOL/IOH and load capacitance shown in (a) of Figure 5 on page 23.
30. When a part with a maximum frequency above 167 MHz is operating at a lower clock frequency, it requires the input timings of the frequency range in which it is operated
and outputs data with the output timings of that frequency range.
31. This part has an internal voltage regulator; tPOWER is the time that the power is supplied above VDD min initially before a read or write operation can be initiated.
Document Number: 001-00437 Rev. *U
Page 24 of 32
CY7C1518KV18
CY7C1520KV18
Switching Characteristics (continued)
Over the Operating Range
Parameters [29, 30]
Cypress Consortium
Parameter Parameter
333 MHz
Description
300 MHz
250 MHz
Min
Max
Min
Max
Min
Max
Unit
Output Times
tCO
tCHQV
C/C clock rise (or K/K in single
clock mode) to data valid
–
0.45
–
0.45
–
0.45
ns
tDOH
tCHQX
Data output hold after output C/C
clock rise (Active to Active)
–0.45
–
–0.45
–
–0.45
–
ns
tCCQO
tCHCQV
C/C clock rise to echo clock valid
–
0.45
–
0.45
–
0.45
ns
tCQOH
tCHCQX
Echo clock hold after C/C clock
rise
–0.45
–
–0.45
–
–0.45
–
ns
tCQD
tCQHQV
Echo clock high to data valid
–
0.25
–
0.27
–
0.30
ns
tCQDOH
tCQHQX
Echo clock high to data invalid
–0.25
–
–0.27
–
–0.30
–
ns
tCQH
tCQHCQL
Output clock (CQ/CQ) HIGH [32]
1.25
–
1.40
–
1.75
–
ns
tCQHCQH
tCQHCQH
CQ clock rise to CQ clock rise
(rising edge to rising edge) [32]
1.25
–
1.40
–
1.75
–
ns
tCHZ
tCHQZ
Clock (C/C) rise to High Z (Active
to High Z) [33, 34]
–
0.45
–
0.45
–
0.45
ns
tCLZ
tCHQX1
Clock (C/C) rise to Low Z [33, 34]
–0.45
–
–0.45
–
–0.45
–
ns
tKC Var
Clock phase jitter
–
0.20
–
0.20
–
0.20
ns
20
–
20
–
20
–
s
30
–
30
–
30
–
ns
PLL Timing
tKC Var
tKC lock
tKC lock
PLL lock time (K, C)
tKC Reset
tKC Reset
K static to PLL reset
[35]
Notes
32. These parameters are extrapolated from the input timing parameters (tCYC/2 – 250 ps, where 250 ps is the internal jitter). These parameters are only guaranteed by
design and are not tested in production.
33. tCHZ, tCLZ are specified with a load capacitance of 5 pF as in (b) of Figure 5 on page 23. Transition is measured 100 mV from steady-state voltage.
34. At any voltage and temperature tCHZ is less than tCLZ and tCHZ less than tCO.
35. For frequencies 300 MHz or below, the Cypress QDR II devices surpass the QDR consortium specification for PLL lock time (tKC lock) of 20 µs (min. spec.) and will
lock after 1024 clock cycles (min. spec.), after a stable clock is presented, per the previous 90 nm version.
Document Number: 001-00437 Rev. *U
Page 25 of 32
CY7C1518KV18
CY7C1520KV18
Switching Waveforms
Read/Write/Deselect Sequence
Figure 6. Read/Write/Deselect Sequence [36, 37, 38]
Notes
36. Q00 refers to output from address A0. Q01 refers to output from the next internal burst address following A0, that is, A0 + 1.
37. Outputs are disabled (High Z) one clock cycle after a NOP.
38. In this example, if address A4 = A3, then data Q40 = D30 and Q41 = D31. Write data is forwarded immediately as read results. This note applies to the whole diagram.
Document Number: 001-00437 Rev. *U
Page 26 of 32
CY7C1518KV18
CY7C1520KV18
Ordering Information
The following table contains only the parts that are currently available. If you do not see what you are looking for, contact your local
sales representative. For more information, visit the Cypress website at www.cypress.com and refer to the product summary page at
http://www.cypress.com/products
Cypress maintains a worldwide network of offices, solution centers, manufacturer’s representatives and distributors. To find the office
closest to you, visit us at http://www.cypress.com/go/datasheet/offices.
Speed
(MHz)
333
Package
Diagram
Ordering Code
Package Type
CY7C1518KV18-333BZC
51-85180 165-ball FBGA (13 × 15 × 1.4 mm)
CY7C1518KV18-333BZXC
51-85180 165-ball FBGA (13 × 15 × 1.4 mm) Pb-free
Operating
Range
Commercial
CY7C1520KV18-333BZXC
300
CY7C1520KV18-333BZXI
51-85180 165-ball FBGA (13 × 15 × 1.4 mm) Pb-free
Industrial
CY7C1518KV18-300BZXC
51-85180 165-ball FBGA (13 × 15 × 1.4 mm) Pb-free
Commercial
CY7C1518KV18-300BZXI
51-85180 165-ball FBGA (13 × 15 × 1.4 mm) Pb-free
Industrial
CY7C1520KV18-300BZXI
250
CY7C1520KV18-250BZC
51-85180 165-ball FBGA (13 × 15 × 1.4 mm)
CY7C1518KV18-250BZXC
51-85180 165-ball FBGA (13 × 15 × 1.4 mm) Pb-free
Commercial
CY7C1520KV18-250BZXC
CY7C1518KV18-250BZI
51-85180 165-ball FBGA (13 × 15 × 1.4 mm)
Industrial
CY7C1520KV18-250BZI
CY7C1518KV18-250BZXI
51-85180 165-ball FBGA (13 × 15 × 1.4 mm) Pb-free
CY7C1520KV18-250BZXI
Ordering Code Definitions
CY 7
C 15XX K V18 - XXX
BZ
X X
Temperature Range: X = C or I
C = Commercial; I = Industrial
Pb-free
Package Type:
BZ = 165-ball FBGA
Frequency range: 333 MHz or 300 MHz or 250 MHz
V18 = 1.8 V
Die Revision
Part Identifier:
15XX = 1518 or 1520
Technology Code: C = CMOS
Marketing Code: 7 = SRAM
Company ID: CY = Cypress
Document Number: 001-00437 Rev. *U
Page 27 of 32
CY7C1518KV18
CY7C1520KV18
Package Diagram
Figure 7. 165-ball FBGA (13 × 15 × 1.4 mm) BB165D/BW165D (0.5 Ball Diameter) Package Outline, 51-85180
51-85180 *G
Document Number: 001-00437 Rev. *U
Page 28 of 32
CY7C1518KV18
CY7C1520KV18
Acronyms
Acronym
Document Conventions
Description
Units of Measure
DDR
Double Data Rate
FBGA
Fine-Pitch Ball Grid Array
°C
degree Celsius
HSTL
High-Speed Transceiver Logic
k
kilohm
I/O
Input/Output
MHz
megahertz
JEDEC
Joint Electron Devices Engineering Council
µA
microampere
JTAG
Joint Test Action Group
µs
microsecond
LMBU
Logical Multiple Bit Upset
mA
milliampere
LSB
Least Significant Bit
LSBU
Logical Single Bit Upset
MSB
Most Significant Bit
PLL
Phase-Locked Loop
QDR
Quad Data Rate
SEL
Single Event Latch-up
pF
picofarad
SRAM
Static Random Access Memory
V
volt
TAP
Test Access Port
W
watt
TCK
Test Clock
TMS
Test Mode Select
TDI
Test Data-In
TDO
Test Data-Out
TTL
Transistor-Transistor Logic
Document Number: 001-00437 Rev. *U
Symbol
Unit of Measure
ms
millisecond
mm
millimeter
mV
millivolt
ns
nanosecond

ohm
%
percent
Page 29 of 32
CY7C1518KV18
CY7C1520KV18
Document History Page
Document Title: CY7C1518KV18/CY7C1520KV18, 72-Mbit DDR-II SRAM Two-Word Burst Architecture
Document Number: 001-00437
Rev.
ECN No.
Orig. of
Change
Submission
Date
**
374703
SYT
See ECN
New data sheet.
*A
1103864
VKN
See ECN
Updated Selection Guide (Updated Maximum Operating Current parameter).
Updated Ordering Information (Updated part numbers, added disclaimer at the
top of the Ordering Information table).
*B
1699246
VKN /
AESA
See ECN
Changed status from Advance Information to Preliminary.
*C
1939726
VKN /
AESA
See ECN
Updated Electrical Characteristics (Added Note 25 and referred the same Note
in IDD parameter).
Updated Switching Characteristics (Updated Note 32, changed minimum value
of tKC lock parameter from 1024 cycles to 20 s).
*D
2606839
VKN /
PYRS
11/13/08
Updated Identification Register Definitions (Changed Revision Number (31:29)
from 001 to 000).
Updated Power Up Sequence in DDR II SRAM (Updated description and
Figure 4).
Updated Maximum Ratings (Changed Ambient Temperature with Power
Applied from “–10 °C to +85 °C” to “–55 °C to +125 °C”).
Updated Thermal Resistance (Replaced values of JA and JC parameters
from TBD to respective Thermal Values for 165-ball FBGA Package).
Updated Ordering Information (Updated Package Type column (Changed the
package size from 15 × 17 × 1.4 mm to 13 × 15 × 1.4 mm)).
Updated Package Diagram (Changed the package size from 15 × 17 × 1.4 mm
to 13 × 15 × 1.4 mm (Removed spec 51-85195 and included 51-85180)).
*E
2681899
VKN /
PYRS
04/01/2009
Changed status from Preliminary to Final.
Updated Ordering Information (Modified the disclaimer for the Ordering
information).
Post to external web.
*F
2747635
VKN /
AESA
08/03/2009
Added Neutron Soft Error Immunity.
Updated Ordering Information (By including parts that are available, and
modified the disclaimer for the Ordering information).
*G
2767155
VKN /
AESA
09/23/2009
Updated Capacitance (Changed value of Input Capacitance (CIN) from 2 pF to
4 pF, changed value of Output Capacitance (CO) from 3 pF to 4 pF).
Updated Ordering Information (Modified the disclaimer for the Ordering
information).
*H
2870201
NJY
02/01/2010
No technical updates.
*I
2896003
NJY
03/19/2010
Updated Ordering Information (Removed inactive parts).
Description of Change
*J
3216622
NJY
04/05/2011
Updated to new template.
*K
3298193
OSN
06/30/2011
Updated Ordering Information (Removed pruned part number
CY7C1520KV18-200BZC).
*L
3404578
PRIT
10/13/2011
Updated Ordering Information (Removed prune part number
CY7C1520KV18-300BZI).
Updated to new template.
*M
3441341
PRIT
11/21/2011
Updated Switching Characteristics (Added Note 35 and referred the same note
in description of tKC lock parameter).
Updated Package Diagram.
Document Number: 001-00437 Rev. *U
Page 30 of 32
CY7C1518KV18
CY7C1520KV18
Document History Page (continued)
Document Title: CY7C1518KV18/CY7C1520KV18, 72-Mbit DDR-II SRAM Two-Word Burst Architecture
Document Number: 001-00437
Rev.
ECN No.
Orig. of
Change
Submission
Date
Description of Change
*N
3598158
PRIT
04/24/2012
Updated Features (Removed CY7C1516KV18, CY7C1527KV18 related
information).
Updated Configurations (Removed CY7C1516KV18, CY7C1527KV18 related
information).
Updated Functional Description (Removed CY7C1516KV18, CY7C1527KV18
related information).
Updated Selection Guide (Removed 167 MHz and 200 MHz frequencies
related information, removed CY7C1516KV18, CY7C1527KV18 related
information).
Removed Logic Block Diagram – CY7C1516KV18.
Removed Logic Block Diagram – CY7C1527KV18.
Updated Pin Configurations (Removed CY7C1516KV18, CY7C1527KV18
related information).
Updated Pin Definitions (Removed CY7C1516KV18, CY7C1527KV18 related
information).
Updated Functional Overview (Removed CY7C1516KV18, CY7C1527KV18
related information).
Updated Truth Table (Removed CY7C1516KV18, CY7C1527KV18 related
information).
Updated Write Cycle Descriptions (Removed CY7C1516KV18 related
information).
Removed Write Cycle Descriptions (Corresponding to CY7C1527KV18).
Updated Identification Register Definitions (Removed CY7C1516KV18,
CY7C1527KV18 related information).
Updated Electrical Characteristics (Updated DC Electrical Characteristics
(Removed 167 MHz and 200 MHz frequencies related information, removed
CY7C1516KV18, CY7C1527KV18 related information)).
Updated Switching Characteristics (Removed 167 MHz and 200 MHz
frequencies related information).
Updated Ordering Information (Updated part numbers).
Updated Package Diagram (spec 51-85180 (changed revision from *D to *E)).
*O
3666992
PRIT
07/05/2012
No technical updates.
Completing Sunset review.
*P
3841481
YHB /
GOPA
12/14/2012
Updated Ordering Information (Updated part numbers).
Updated Package Diagram (spec 51-85180 (Changed revision from *E to *F)).
*Q
4371693
PRIT
05/06/2014
Updated Application Example:
Updated Figure 2.
Updated Thermal Resistance:
Updated values of JA and JC parameters.
Included JB parameter and its details.
Updated to new template.
*R
4489182
PRIT
08/31/2014
Updated Ordering Information (Updated part numbers).
*S
4569232
PRIT
11/14/2014
Updated Functional Description:
Added “For a complete list of related documentation, click here.” at the end.
*T
4811102
PRIT
06/25/2015
Updated Ordering Information (Updated part numbers).
Updated to new template.
Completing Sunset Review.
*U
5125408
PRIT
02/04/2016
Updated Switching Waveforms:
Updated Read/Write/Deselect Sequence:
Updated Figure 6.
Updated Package Diagram:
spec 51-85180 – Changed revision from *F to *G.
Document Number: 001-00437 Rev. *U
Page 31 of 32
CY7C1518KV18
CY7C1520KV18
Sales, Solutions, and Legal Information
Worldwide Sales and Design Support
Cypress maintains a worldwide network of offices, solution centers, manufacturer’s representatives, and distributors. To find the office
closest to you, visit us at Cypress Locations.
PSoC® Solutions
Products
Automotive
Clocks & Buffers
Interface
Lighting & Power Control
Memory
PSoC
Touch Sensing
USB Controllers
Wireless/RF
cypress.com/go/automotive
cypress.com/go/clocks
cypress.com/go/interface
cypress.com/go/powerpsoc
cypress.com/go/memory
cypress.com/go/psoc
cypress.com/go/touch
psoc.cypress.com/solutions
PSoC 1 | PSoC 3 | PSoC 4 | PSoC 5LP
Cypress Developer Community
Community | Forums | Blogs | Video | Training
Technical Support
cypress.com/go/support
cypress.com/go/USB
cypress.com/go/wireless
© Cypress Semiconductor Corporation, 2005-2016. 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: 001-00437 Rev. *U
Revised February 4, 2016
Page 32 of 32
QDR RAMs and Quad Data Rate RAMs comprise a new family of products developed by Cypress, IDT, NEC, Renesas, and Samsung. All products and company names mentioned in this document
may be the trademarks of their respective holders.
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