CY7C2642KV18, CY7C2644KV18 144-Mbit QDR® II+ SRAM Two-Word Burst Architecture (2.0 Cycle Read Latency) with ODT Datasheet.pdf

CY7C2642KV18/CY7C2644KV18
®
144-Mbit QDR II+ SRAM Two-Word
Burst Architecture (2.0 Cycle Read Latency) with ODT
144-Mbit QDR ® II+ SRAM Two-Word Burst Architecture (2.0 Cycle Read Latency) with ODT
Features
■
■
Separate independent read and write data ports
❐ Supports concurrent transactions
■
333-MHz clock for high bandwidth
■
Two-word burst for reducing address bus frequency
■
Double data rate (DDR) interfaces on both read and write ports
(data transferred at 666 MHz) at 333 MHz
■
Available in 2.0-clock cycle latency
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
On-die termination (ODT) feature
❐ Supported for D[x:0], BWS[x:0], and K/K inputs
■ 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
■
Quad data rate (QDR®) II+ operates with 2.0-cycle read latency
when DOFF is asserted high
■
Operates similar to QDR I device with one cycle read latency
when DOFF is asserted low
■
Available in × 18, and × 36 configurations
■
Full data coherency, providing most current data
■
Core VDD = 1.8 V± 0.1 V; I/O VDDQ = 1.4 V to VDD [1]
❐ Supports both 1.5 V and 1.8 V I/O supply
■
High-speed transceiver logic (HSTL) inputs and variable drive
HSTL output buffers
■
Available in 165-ball fine pitch ball grid array (FBGA) package
(15 × 17 × 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
Configurations
With Read Cycle Latency of 2.0 cycles:
CY7C2642KV18 – 8 M × 18
CY7C2644KV18 – 4 M × 36
Functional Description
The CY7C2642KV18, and CY7C2644KV18 are 1.8-V
synchronous pipelined SRAMs, equipped with QDR® II+
architecture. Similar to QDR II architecture, QDR II+ architecture
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 I/O devices. Access to each port is 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 two 18-bit words
(CY7C2642KV18), or 36-bit words (CY7C2644KV18) that burst
sequentially into or out of the device. Because data can be
transferred into and out of the device on every rising edge of both
input clocks (K and K), memory bandwidth is maximized while
simplifying system design by eliminating bus “turn arounds”.
These devices have an ODT feature supported for D[x:0],
BWS[x:0], and K/K inputs, which helps eliminate external
termination resistors, reduce cost, reduce board area, and
simplify board routing.
Depth expansion is accomplished with port selects, which
enables each port to operate independently.
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.
For a complete list of related documentation, click here.
Selection Guide
Description
333 MHz
Maximum operating frequency
Maximum operating current
300 MHz
Unit
333
300
MHz
× 18
970
Not Offered
mA
× 36
1160
1080
Note
1. The Cypress QDR II+ devices surpass the QDR consortium specification and can support VDDQ = 1.4 V to VDD.
Cypress Semiconductor Corporation
Document Number: 001-44138 Rev. *P
•
198 Champion Court
•
San Jose, CA 95134-1709
•
408-943-2600
Revised December 31, 2015
CY7C2642KV18/CY7C2644KV18
Logic Block Diagram – CY7C2642KV18
K
CLK
Gen.
DOFF
22
Address
Register
Read Add. Decode
K
Write
Reg
4M x 18 Array
Address
Register
Write
Reg
4M x 18 Array
A(21:0)
22
18
Write Add. Decode
D[17:0]
A(21:0)
RPS
Control
Logic
Read Data Reg.
CQ
36
VREF
WPS
BWS[1:0]
18
Control
Logic
18
Reg.
Reg. 18
Reg.
18
CQ
18
Q[17:0]
QVLD
Logic Block Diagram – CY7C2644KV18
K
CLK
Gen.
DOFF
21
Address
Register
Read Add. Decode
K
Write
Reg
2M x 36 Array
Address
Register
Write
Reg
2M x 36 Array
A(20:0)
21
36
Write Add. Decode
D[35:0]
A(20:0)
RPS
Control
Logic
Read Data Reg.
CQ
72
VREF
WPS
BWS[3:0]
36
Control
Logic
36
Reg.
Reg. 36
Reg.
36
CQ
36
Q[35:0]
QVLD
Document Number: 001-44138 Rev. *P
Page 2 of 30
CY7C2642KV18/CY7C2644KV18
Contents
Pin Configurations ........................................................... 4
Pin Definitions .................................................................. 5
Functional Overview ........................................................ 6
Read Operations ......................................................... 6
Write Operations ......................................................... 7
Byte Write Operations ................................................. 7
Concurrent Transactions ............................................. 7
Depth Expansion ......................................................... 7
Programmable Impedance .......................................... 7
Echo Clocks ................................................................ 7
Valid Data Indicator (QVLD) ........................................ 7
On-Die Termination (ODT) .......................................... 7
PLL .............................................................................. 7
Application Example ........................................................ 8
Truth Table ........................................................................ 9
Write Cycle Descriptions ................................................. 9
Write Cycle Descriptions ............................................... 10
IEEE 1149.1 Serial Boundary Scan (JTAG) .................. 11
Disabling the JTAG Feature ...................................... 11
Test Access Port ....................................................... 11
Performing a TAP Reset ........................................... 11
TAP Registers ........................................................... 11
TAP Instruction Set ................................................... 11
TAP Controller State Diagram ....................................... 13
TAP Controller Block Diagram ...................................... 14
TAP Electrical Characteristics ...................................... 14
TAP AC Switching Characteristics ............................... 15
TAP Timing and Test Conditions .................................. 16
Identification Register Definitions ................................ 17
Scan Register Sizes ....................................................... 17
Instruction Codes ........................................................... 17
Document Number: 001-44138 Rev. *P
Boundary Scan Order .................................................... 18
Power Up Sequence in QDR II+ SRAM ......................... 19
Power Up Sequence ................................................. 19
PLL Constraints ......................................................... 19
Maximum Ratings ........................................................... 20
Operating Range ............................................................. 20
Neutron Soft Error Immunity ......................................... 20
Electrical Characteristics ............................................... 20
DC Electrical Characteristics ..................................... 20
AC Electrical Characteristics ..................................... 22
Capacitance .................................................................... 22
Thermal Resistance ........................................................ 22
AC Test Loads and Waveforms ..................................... 22
Switching Characteristics .............................................. 23
Switching Waveforms .................................................... 24
Read/Write/Deselect Sequence ................................ 24
Ordering Information ...................................................... 25
Ordering Code Definitions ......................................... 25
Package Diagram ............................................................ 26
Acronyms ........................................................................ 27
Document Conventions ................................................. 27
Units of Measure ....................................................... 27
Document History Page ................................................. 28
Sales, Solutions, and Legal Information ...................... 30
Worldwide Sales and Design Support ....................... 30
Products .................................................................... 30
PSoC® Solutions ...................................................... 30
Cypress Developer Community ................................. 30
Technical Support ..................................................... 30
Page 3 of 30
CY7C2642KV18/CY7C2644KV18
Pin Configurations
The pin configurations for CY7C2642KV18, and CY7C2644KV18 follow. [2]
Figure 1. 165-ball FBGA (15 × 17 × 1.4 mm) pinout
CY7C2642KV18 (8 M × 18)
1
2
3
4
5
6
7
8
9
10
11
A
CQ
A
A
WPS
BWS1
K
NC/288M
RPS
A
A
CQ
B
NC
Q9
D9
A
NC
K
BWS0
A
NC
NC
Q8
C
NC
NC
D10
VSS
A
A
A
VSS
NC
Q7
D8
D
NC
D11
Q10
VSS
VSS
VSS
VSS
VSS
NC
NC
D7
E
NC
NC
Q11
VDDQ
VSS
VSS
VSS
VDDQ
NC
D6
Q6
F
NC
Q12
D12
VDDQ
VDD
VSS
VDD
VDDQ
NC
NC
Q5
G
NC
D13
Q13
VDDQ
VDD
VSS
VDD
VDDQ
NC
NC
D5
H
DOFF
VREF
VDDQ
VDDQ
VDD
VSS
VDD
VDDQ
VDDQ
VREF
ZQ
J
NC
NC
D14
VDDQ
VDD
VSS
VDD
VDDQ
NC
Q4
D4
K
NC
NC
Q14
VDDQ
VDD
VSS
VDD
VDDQ
NC
D3
Q3
L
NC
Q15
D15
VDDQ
VSS
VSS
VSS
VDDQ
NC
NC
Q2
M
NC
NC
D16
VSS
VSS
VSS
VSS
VSS
NC
Q1
D2
N
NC
D17
Q16
VSS
A
A
A
VSS
NC
NC
D1
P
NC
NC
Q17
A
A
QVLD
A
A
NC
D0
Q0
R
TDO
TCK
A
A
A
ODT
A
A
A
TMS
TDI
1
2
3
4
5
6
7
8
9
10
11
A
CQ
NC/288M
A
WPS
BWS2
K
BWS1
RPS
A
A
CQ
B
Q27
Q18
D18
A
BWS3
K
BWS0
A
D17
Q17
Q8
C
D27
Q28
D19
VSS
A
A
A
VSS
D16
Q7
D8
D
D28
D20
Q19
VSS
VSS
VSS
VSS
VSS
Q16
D15
D7
E
Q29
D29
Q20
VDDQ
VSS
VSS
VSS
VDDQ
Q15
D6
Q6
F
Q30
Q21
D21
VDDQ
VDD
VSS
VDD
VDDQ
D14
Q14
Q5
CY7C2644KV18 (4 M × 36)
G
D30
D22
Q22
VDDQ
VDD
VSS
VDD
VDDQ
Q13
D13
D5
H
DOFF
VREF
VDDQ
VDDQ
VDD
VSS
VDD
VDDQ
VDDQ
VREF
ZQ
J
D31
Q31
D23
VDDQ
VDD
VSS
VDD
VDDQ
D12
Q4
D4
K
Q32
D32
Q23
VDDQ
VDD
VSS
VDD
VDDQ
Q12
D3
Q3
L
Q33
Q24
D24
VDDQ
VSS
VSS
VSS
VDDQ
D11
Q11
Q2
M
D33
Q34
D25
VSS
VSS
VSS
VSS
VSS
D10
Q1
D2
N
D34
D26
Q25
VSS
A
A
A
VSS
Q10
D9
D1
P
Q35
D35
Q26
A
A
QVLD
A
A
Q9
D0
Q0
R
TDO
TCK
A
A
A
ODT
A
A
A
TMS
TDI
Note
2. NC/288M is not connected to the die and can be tied to any voltage level.
Document Number: 001-44138 Rev. *P
Page 4 of 30
CY7C2642KV18/CY7C2644KV18
Pin Definitions
Pin Name
I/O
Pin Description
D[x:0]
InputData input signals. Sampled on the rising edge of K and K clocks during valid write operations.
Synchronous CY7C2642KV18  D[17:0]
CY7C2644KV18  D[35:0]
WPS
InputWrite 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].
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.
CY7C2642KV18  BWS0 controls D[8:0] and BWS1 controls D[17:9].
CY7C2644KV18  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
InputAddress inputs. Sampled on the rising edge of the K (read address) and K (write address) clocks during
Synchronous active read and write operations. These address inputs are multiplexed for both read and write
operations. Internally, the device is organized as 8 M × 18 (2 arrays each of 4 M × 18) for CY7C2642KV18,
and 4 M × 36 (2 arrays each of 2 M × 36) for CY7C2644KV18. Therefore, only 22 address inputs for
CY7C2642KV18, and 21 address inputs for CY7C2644KV18. These inputs are ignored when the
appropriate port is deselected.
Q[x:0]
OutputData output signals. These pins drive out the requested data during a read operation. Valid data is
Synchronous driven out on the rising edge of the K and K clocks during read operations. When the read port is
deselected, Q[x:0] are automatically tri-stated.
CY7C2642KV18  Q[17:0]
CY7C2644KV18  Q[35:0]
RPS
InputRead 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 two sequential transfers.
QVLD
Valid output Valid output indicator. The Q Valid indicates valid output data. QVLD is edge aligned with CQ and CQ.
indicator
ODT [3]
On-die
termination
input pin
On-die termination input. This pin is used for On-Die termination of the input signals. ODT range
selection is made during power up initialization. A low on this pin selects a low range that follows RQ/3.33
for 175  < RQ < 350 (where RQ is the resistor tied to ZQ pin)A high on this pin selects a high range
that follows RQ/1.66 for 175 < RQ < 250 (where RQ is the resistor tied to ZQ pin). When left floating,
a high range termination value is selected by default.
Note
3. On-Die Termination (ODT) feature is supported for D[x:0], BWS[x:0], and K/K inputs.
Document Number: 001-44138 Rev. *P
Page 5 of 30
CY7C2642KV18/CY7C2644KV18
Pin Definitions (continued)
Pin Name
I/O
Pin Description
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]. All accesses are initiated on the rising edge of K.
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
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 timing for the echo clocks is shown in Switching Characteristics on page 23.
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 timing for the echo clocks is shown in the Switching Characteristics on page 23.
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, connect this pin directly to VDDQ, which enables the
minimum impedance mode. This pin cannot be connected directly to GND or left unconnected.
DOFF
Input
PLL turn off  Active low. Connecting this pin to ground turns off the PLL inside the device. The timing
in the operation with the PLL turned off differs from those listed in this data sheet. For normal operation,
connect this pin to a pull up through a 10 K or less pull up resistor. The device behaves in QDR 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 QDR I timing.
TDO
Output
TCK
Input
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/288M
Input
Not connected to the die. Can be tied to any voltage level.
VREF
VDD
VSS
VDDQ
InputReference
Test data-out (TDO) pin for JTAG.
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 CY7C2642KV18, and CY7C2644KV18 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 flows 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 two 18-bit
data transfers in the case of CY7C2642KV18, and two 36-bit
data transfers in the case of CY7C2644KV18 in one clock cycle.
These devices operate with a read latency of two cycles when
DOFF pin is tied high. When DOFF pin is set low or connected
to VSS then the device behaves in QDR I mode with a read
latency of one clock cycle.
Document Number: 001-44138 Rev. *P
Accesses for both ports are initiated on the rising edge of 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[x:0]) pass through input registers
controlled by the input clocks (K and K). All synchronous data
outputs (Q[x:0]) pass through output registers controlled by the
rising edge of the input clocks (K and K) as well.
All synchronous control (RPS, WPS, BWS[x:0]) inputs pass
through input registers controlled by the rising edge of the input
clocks (K and K).
CY7C2642KV18 is described in the following sections. The
same basic descriptions apply to CY7C2644KV18.
Read Operations
The CY7C2642KV18 is organized internally as two arrays of
4 M × 18. Accesses are completed in a burst of two 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 is latched on the rising edge of the K clock. The address
Page 6 of 30
CY7C2642KV18/CY7C2644KV18
presented to the address inputs is stored in the read address
register. Following the next two K clock rise, the corresponding
lowest order 18-bit word of data is driven onto the Q[17:0] using
K as the output timing reference. On the subsequent rising edge
of K, the next 18-bit data word is driven onto the Q[17:0]. The
requested data is valid 0.45 ns from the rising edge of the input
clock (K and K).
When the read port is deselected, the CY7C2642KV18 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
seamless transition between devices without the insertion of wait
states in a depth expanded memory.
Write Operations
Write operations are initiated by asserting WPS active at the
rising edge of the positive input clock (K). On the same K clock
rise the data presented to D[17:0] is latched and stored into the
lower 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 address is latched and 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.
When deselected, the write port ignores all inputs after the
pending write operations have been completed.
Byte Write Operations
Byte write operations are supported by the CY7C2642KV18. 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 can be used to
simplify read, modify, or write operations to a byte write
operation.
Concurrent Transactions
The read and write ports on the CY7C2642KV18 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. The user can start reads and writes in the same clock cycle.
If the ports access the same location at the same time, 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.
Depth Expansion
The CY7C2642KV18 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
Document Number: 001-44138 Rev. *P
does not affect the other port. All pending transactions (read and
write) are completed before the device is deselected.
Programmable Impedance
An external resistor, RQ, must be connected between the ZQ pin
on the SRAM and VSS to enable the SRAM to adjust its output
driver impedance. The value of RQ must be 5 × 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 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
referenced with respect to K. These are free-running clocks and
are synchronized to the input clock of the QDR II+. The timing
for the echo clocks is shown in the Switching Characteristics on
page 23.
Valid Data Indicator (QVLD)
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.
On-Die Termination (ODT)
These devices have an on-die termination feature for data inputs
(D[x:0]), Byte Write Selects (BWS[x:0]), and Input Clocks (K and
K). The termination resistors are integrated within the chip. The
ODT range selection is enabled through ball R6 (ODT pin). The
ODT termination tracks value of RQ where RQ is the resistor tied
to the ZQ pin. ODT range selection is made during power up
initialization. A low on this pin selects a low range that follows
RQ/3.33 for 175 < RQ < 350 (where RQ is the resistor tied
to ZQ pin)A high on this pin selects a high range that follows
RQ/1.66 for 175 < RQ < 250 (where RQ is the resistor tied
to ZQ pin). When left floating, a high range termination value is
selected by default. For a detailed description of ODT
implementation, refer to the application note, AN42468, On-Die
Termination for QDRII+/DDRII+ SRAMs.
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 clocks 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 QDR I mode with one cycle latency and a longer
access time).
Page 7 of 30
CY7C2642KV18/CY7C2644KV18
Application Example
Figure 2 shows two QDR II+ used in an application.
Figure 2. Application Example (Width Expansion)
SRAM#1
D[x:0]
A
RPS
WPS
ZQ
CQ/CQ
Q[x:0]
BWS K K
RQ
SRAM#2
D[x:0]
A
RPS
WPS
ZQ
CQ/CQ
Q[x:0]
BWS K K
RQ
DATA IN[2x:0]
DATA OUT [2x:0]
ADDRESS
RPS
WPS
BWS
CLKIN1/CLKIN1
CLKIN2/CLKIN2
SOURCE K
SOURCE K
FPGA / ASIC
Document Number: 001-44138 Rev. *P
Page 8 of 30
CY7C2642KV18/CY7C2644KV18
Truth Table
The truth table for CY7C2642KV18, and CY7C2644KV18 follows. [4, 5, 6, 7, 8, 9]
Operation
K
RPS WPS
DQ
DQ
Write Cycle:
Load address on the rising edge of K;
input write data on K and K rising edges.
L–H
X
L
D(A) at K(t) 
D(A + 1) at K(t) 
Read Cycle: (2.0 cycle Latency)
Load address on the rising edge of K;
wait two cycles; read data on K and K rising edges.
L–H
L
X
Q(A) at K(t + 2) 
Q(A + 1) at K(t + 2) 
NOP: No Operation
L–H
H
H
D=X
Q = High Z
D=X
Q = High Z
Stopped
X
X
Previous State
Previous State
Standby: Clock Stopped
Write Cycle Descriptions
The write cycle description table for CY7C2642KV18 follows. [4, 10]
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
CY7C2642KV18 both bytes (D[17:0]) are written into the device.
L–H During the data portion of a write sequence:
CY7C2642KV18 both bytes (D[17:0]) are written into the device.
–
During the data portion of a write sequence:
CY7C2642KV18 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
CY7C2642KV18 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
CY7C2642KV18 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
CY7C2642KV18 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
4. X = “Don't Care,” H = Logic HIGH, L = Logic LOW, represents rising edge.
5. Device powers up deselected with the outputs in a tri-state condition.
6. “A” represents address location latched by the devices when transaction was initiated. A + 1 represents the internal address sequence in the burst.
7. “t” represents the cycle at which a Read/Write operation is started. t + 1, and t + 2 are the first, and second clock cycles respectively succeeding the “t” clock cycle.
8. Data inputs are registered at K and K rising edges. Data outputs are delivered on K and K rising edges as well.
9. 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.
10. Is based on a write cycle that was initiated in accordance with the Truth Table. 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: 001-44138 Rev. *P
Page 9 of 30
CY7C2642KV18/CY7C2644KV18
Write Cycle Descriptions
The write cycle description table for CY7C2644KV18 follow. [11, 12]
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
11. X = “Don't Care,” H = Logic HIGH, L = Logic LOW, represents rising edge.
12. 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: 001-44138 Rev. *P
Page 10 of 30
CY7C2642KV18/CY7C2644KV18
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 I/O 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 on
loading the instruction register, see the TAP Controller State
Diagram on page 13. 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 17).
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 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
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: 001-44138 Rev. *P
Instruction Register
Three-bit instructions can be 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 14. 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 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 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.
The Boundary Scan Order on page 18 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 can be 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 17.
TAP Instruction Set
Eight different instructions are possible with the three-bit
instruction register. All combinations are listed in Instruction
Codes on page 17. 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 11 of 30
CY7C2642KV18/CY7C2644KV18
IDCODE
BYPASS
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.
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.
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 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.
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.
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 TRI-STATE
IEEE Standard 1149.1 mandates that the TAP controller be able
to put the output bus into a tri-state mode.
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.
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 pre-set low 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.
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.
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.
Document Number: 001-44138 Rev. *P
Page 12 of 30
CY7C2642KV18/CY7C2644KV18
TAP Controller State Diagram
The state diagram for the TAP controller follows. [13]
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
13. The 0/1 next to each state represents the value at TMS at the rising edge of TCK.
Document Number: 001-44138 Rev. *P
Page 13 of 30
CY7C2642KV18/CY7C2644KV18
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 [14, 15, 16]
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
GND  VI  VDD
0.65 × VDD VDD + 0.3
V
–0.3
0.35 × VDD
V
–5
5
A
Notes
14. These characteristics pertain to the TAP inputs (TMS, TCK, TDI and TDO). Parallel load levels are specified in the Electrical Characteristics on page 20.
15. Overshoot: VIH(AC) < VDDQ + 0.35 V (Pulse width less than tCYC/2), Undershoot: VIL(AC) > 0.3 V (Pulse width less than tCYC/2).
16. All voltage referenced to ground.
Document Number: 001-44138 Rev. *P
Page 14 of 30
CY7C2642KV18/CY7C2644KV18
TAP AC Switching Characteristics
Over the Operating Range
Parameter [17, 18]
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
17. tCS and tCH refer to the setup and hold time requirements of latching data from the boundary scan register.
18. Test conditions are specified using the load in TAP AC Test Conditions. tR/tF = 1 ns.
Document Number: 001-44138 Rev. *P
Page 15 of 30
CY7C2642KV18/CY7C2644KV18
TAP Timing and Test Conditions
Figure 3 shows the TAP timing and test conditions. [19]
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
19. Test conditions are specified using the load in TAP AC Test Conditions. tR/tF = 1 ns.
Document Number: 001-44138 Rev. *P
Page 16 of 30
CY7C2642KV18/CY7C2644KV18
Identification Register Definitions
Value
Instruction Field
CY7C2642KV18
Revision Number (31:29)
Description
CY7C2644KV18
000
000
Cypress Device ID (28:12)
11010010100010011
11010010100100011
Cypress JEDEC ID (11:1)
00000110100
00000110100
ID Register Presence (0)
1
1
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 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: 001-44138 Rev. *P
Page 17 of 30
CY7C2642KV18/CY7C2644KV18
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: 001-44138 Rev. *P
Page 18 of 30
CY7C2642KV18/CY7C2644KV18
Power Up Sequence in QDR II+ SRAM
PLL Constraints
QDR 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: 001-44138 Rev. *P
V DD / V DDQ Stable (< +/- 0.1V DC per 50ns )
Fix HIGH (or tie to VDDQ)
Page 19 of 30
CY7C2642KV18/CY7C2644KV18
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
Industrial
Ambient temperature
with power applied ................................... –55 °C to +125 °C
Commercial
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 input voltage
VDD [21]
VDDQ [21]
–40 °C to +85 °C
1.8 ± 0.1 V
1.4 V to
VDD
0 °C to +70 °C
Neutron Soft Error Immunity
DC applied to outputs in High Z ........ –0.5 V to VDDQ + 0.3 V
[20]
Ambient
Temperature (TA)
........................... –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/
Mb
LMBU
Logical
multi-bit
upsets
25 °C
0
0.01
FIT/
Mb
SEL
Single event
latch up
85 °C
0
0.1
FIT/
Dev
* 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 [22]
Min
Typ
Max
Unit
VDD
Power supply voltage
1.7
1.8
1.9
V
VDDQ
I/O supply voltage
1.4
1.5
VDD
V
VOH
Output high voltage
Note 23
VDDQ/2 – 0.12
–
VDDQ/2 + 0.12
V
VOL
Output low voltage
Note 24
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
VOL(LOW)
Output low voltage
IOL = 0.1 mA, Nominal Impedance
VSS
–
0.2
V
VIH
Input high voltage
VREF + 0.1
–
VDDQ + 0.15
V
VIL
Input low voltage
IX
Input leakage current
IOZ
Output leakage current
VREF
Description
Input reference voltage
Test Conditions
[25]
–0.15
–
VREF – 0.1
V
GND  VI  VDDQ
2
–
2
A
GND  VI  VDDQ, Output Disabled
2
–
2
A
0.68
0.75
0.95
V
Typical Value = 0.75 V
Notes
20. Overshoot: VIH(AC) < VDDQ + 0.35 V (Pulse width less than tCYC/2), Undershoot: VIL(AC) > 0.3 V (Pulse width less than tCYC/2).
21. Power up: Assumes a linear ramp from 0 V to VDD(min) within 200 ms. During this time VIH < VDD and VDDQ < VDD.
22. All voltage referenced to ground.
23. Output are impedance controlled. IOH = (VDDQ/2)/(RQ/5) for values of 175   RQ  350 .
24. Output are impedance controlled. IOL = (VDDQ/2)/(RQ/5) for values of 175   RQ  350 .
25. 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: 001-44138 Rev. *P
Page 20 of 30
CY7C2642KV18/CY7C2644KV18
Electrical Characteristics (continued)
Over the Operating Range
DC Electrical Characteristics (continued)
Over the Operating Range
Parameter [22]
IDD
[26]
ISB1
Description
VDD Operating Supply
Automatic Power Down
Current
Test Conditions
VDD = Max,
IOUT = 0 mA,
f = fMAX = 1/tCYC
Min
Typ
Max
Unit
333 MHz (× 18)
–
–
970
mA
(× 36)
–
–
1160
300 MHz (× 36)
–
–
1080
mA
Max VDD,
333 MHz (× 18)
Both Ports Deselected,
(× 36)
VIN  VIH or VIN  VIL,
300 MHz (× 36)
f = fMAX = 1/tCYC,
Inputs Static
–
–
410
mA
–
–
410
–
–
390
mA
Note
26. The operation current is calculated with 50% read cycle and 50% write cycle.
Document Number: 001-44138 Rev. *P
Page 21 of 30
CY7C2642KV18/CY7C2644KV18
AC Electrical Characteristics
Over the Operating Range
Parameter [27]
Description
Test Conditions
Min
Typ
Max
Unit
VIH
Input high voltage
VREF + 0.2
–
VDDQ + 0.24
V
VIL
Input low voltage
–0.24
–
VREF – 0.2
V
Max
Unit
4
pF
4
pF
Capacitance
Parameter [28]
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 [28]
JA (0 m/s)
JA (1 m/s)
Description
165-ball FBGA Unit
Package
Test Conditions
Thermal resistance
(junction to ambient)
Socketed on a 170 × 220 × 2.35 mm, eight-layer printed
circuit board
JA (3 m/s)
12.23
°C/W
11.17
°C/W
10.42
°C/W
JB
Thermal resistance
(junction to board)
9.34
°C/W
JC
Thermal resistance
(junction to case)
2.10
°C/W
AC Test Loads and Waveforms
Figure 5. AC Test Loads and Waveforms
VREF = 0.75 V
VREF
0.75 V
VREF
OUTPUT
DEVICE
UNDER
TEST
ZQ
Z0 = 50 
RL = 50 
VREF = 0.75 V
R = 50 
ALL INPUT PULSES
1.25 V
0.75 V
OUTPUT
DEVICE
UNDER
TEST ZQ
RQ =
250 
(a)
0.75 V
INCLUDING
JIG AND
SCOPE
5 pF
[29]
0.25 V
SLEW RATE= 2 V/ns
RQ =
250 
(b)
Notes
27. Overshoot: VIH(AC) < VDDQ + 0.35 V (Pulse width less than tCYC/2), Undershoot: VIL(AC) > 0.3 V (Pulse width less than tCYC/2).
28. Tested initially and after any design or process change that may affect these parameters.
29. Unless otherwise noted, test conditions are based on 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: 001-44138 Rev. *P
Page 22 of 30
CY7C2642KV18/CY7C2644KV18
Switching Characteristics
Over the Operating Range
Parameters [30, 31]
333 MHz
Description
Cypress Consortium
Parameter Parameter
VDD(typical) to the first access [32]
tPOWER
300 MHz
Min
Max
Min
Max
1
–
1
–
Unit
ms
tCYC
tKHKH
K clock cycle time
3.0
8.4
3.3
8.4
ns
tKH
tKHKL
Input clock (K/K) high
0.4
–
0.4
–
tCYC
tKL
tKLKH
Input clock (K/K) low
0.4
–
0.4
–
tCYC
tKHKH
tKHKH
K clock rise to K clock rise (rising edge to rising edge)
1.35
–
1.49
–
ns
Setup Times
tSA
tAVKH
Address setup to K clock rise
0.3
–
0.3
–
ns
tSC
tIVKH
Control setup to K clock rise (RPS, WPS)
0.3
–
0.3
–
ns
tSCDDR
tIVKH
DDR control setup to clock (K/K) rise (BWS0, BWS1, BWS2, BWS3)
0.3
–
0.3
–
ns
tSD
tDVKH
D[X:0] setup to clock (K/K) rise
0.3
–
0.3
–
ns
tHA
tKHAX
Address hold after K clock rise
0.3
–
0.3
–
ns
tHC
tKHIX
Control hold after K clock rise (RPS, WPS)
0.3
–
0.3
–
ns
tHCDDR
tKHIX
DDR control hold after clock (K/K) rise (BWS0, BWS1, BWS2, BWS3)
0.3
–
0.3
–
ns
tHD
tKHDX
D[X:0] hold after clock (K/K) rise
0.3
–
0.3
–
ns
–
0.45
–
0.45
ns
–0.45
–
–0.45
–
ns
–
0.45
–
0.45
ns
Hold Times
Output Times
tCO
tCHQV
K/K clock rise to data valid
tDOH
tCHQX
Data output hold after output K/K clock rise (active to active)
tCCQO
tCHCQV
K/K clock rise to echo clock valid
tCQOH
tCHCQX
–
–0.45
–
ns
tCQHQV
Echo clock hold after K/K clock rise
Echo clock high to data valid
–0.45
tCQD
–
0.25
–
0.27
ns
tCQDOH
tCQHQX
Echo clock high to data invalid
–0.25
–
–0.27
–
ns
tCQH
tCQHCQL
Output clock (CQ/CQ) high [33]
1.25
–
1.40
–
ns
1.25
–
1.40
–
ns
–
0.45
–
0.45
ns
–0.45
–
–0.45
–
ns
–0.20
0.20
–0.20
0.20
ns
tCQHCQH
tCQHCQH
CQ clock rise to CQ clock rise (rising edge to rising edge)
tCHZ
tCHQZ
Clock (K/K) rise to high Z (active to high Z) [34, 35]
tCLZ
tQVLD
tCHQX1
Clock (K/K) rise to low Z
[34, 35]
[36]
[33]
tCQHQVLD
Echo clock high to QVLD valid
tKC Var
tKC Var
Clock phase jitter
–
0.20
–
0.20
ns
tKC lock
tKC lock
PLL lock time (K)
20
–
20
–
s
tKC Reset
tKC Reset
K static to PLL reset [37]
30
–
30
–
ns
PLL Timing
Notes
30. Unless otherwise noted, test conditions are based on 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 22.
31. When a part with a maximum frequency above 200 MHz 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.
32. This part has a voltage regulator internally; tPOWER is the time that the power must be supplied above VDD minimum initially before initiating a read or write operation.
33. 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.
34. tCHZ, tCLZ, are specified with a load capacitance of 5 pF as in part (b) of Figure 5 on page 22. Transition is measured  100 mV from steady state voltage.
35. At any voltage and temperature tCHZ is less than tCLZ and tCHZ less than tCO.
36. tQVLD spec is applicable for both rising and falling edges of QVLD signal.
37. Hold to >VIH or <VIL.
Document Number: 001-44138 Rev. *P
Page 23 of 30
CY7C2642KV18/CY7C2644KV18
Switching Waveforms
Read/Write/Deselect Sequence
Figure 6. Waveform for 2.0 Cycle Read Latency [38, 39, 40]
READ
1
WRITE
2
READ
3
READ
5
WRITE
4
NOP
7
WRITE
6
WRITE
8
NOP
9
10
11
12
K
tKH
tKHKH
tCYC
tKL
K
RPS
tSC tHC
WPS
A
D
A0
D10
A1
A2
tSA tHA
tSA tHA
D11
D30
A3
A4
A5
D31
D50
D51
A6
D60
D61
tSD tHD
tSD tHD
tQVLD
QVLD
tQVLD
Q
tCQD
tCO
tCLZ
Q00
tCHZ
tDOH
Q01
Q20
(Read Latency = 2.0 Cycles)
Q21
Q40
Q41
tCQDOH
tCCQO
CQ
tCQH
tCQHCQH
tCQOH
tCCQO
CQ
tCQOH
DON’T CARE
UNDEFINED
Notes
38. Q00 refers to output from address A0. Q01 refers to output from the next internal burst address following A0, that is, A0 + 1.
39. Outputs are disabled (High Z) one clock cycle after a NOP.
40. In this example, if address A0 = A1, then data Q00 = D10 and Q01 = D11. Write data is forwarded immediately as read results. This note applies to the whole diagram.
Document Number: 001-44138 Rev. *P
Page 24 of 30
CY7C2642KV18/CY7C2644KV18
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)
Ordering Code
Package
Diagram
Package Type
Operating
Range
300
CY7C2644KV18-300BZXI
51-85195 165-ball FBGA (15 × 17 × 1.4 mm) Pb-free
Industrial
333
CY7C2644KV18-333BZI
51-85195 165-ball FBGA (15 × 17 × 1.4 mm)
Industrial
CY7C2644KV18-333BZXI
51-85195 165-ball FBGA (15 × 17 × 1.4 mm) Pb-free
Industrial
CY7C2642KV18-333BZXC
51-85195 165-ball FBGA (15 × 17 × 1.4 mm) Pb-free
Commercial
Ordering Code Definitions
CY
7
C 264X K V18 - 3XX BZ
X
X
Temperature Grade: X = I or C
I = Industrial; C = Commercial
Pb-free
Package Type: BZ = 165-ball FBGA
Frequency Range: 3XX = 300 or 333 MHz
V18 = 1.8 V
Die Revision
Part Identifier: 264X = 2644 or 2642
Technology Code: C = CMOS
Marketing Code: 7 = SRAM
Company ID: CY = Cypress
Document Number: 001-44138 Rev. *P
Page 25 of 30
CY7C2642KV18/CY7C2644KV18
Package Diagram
Figure 7. 165-ball FBGA (15 × 17 × 1.40 mm) (0.50 Ball Diameter) Package Outline, 51-85195
51-85195 *D
Document Number: 001-44138 Rev. *P
Page 26 of 30
CY7C2642KV18/CY7C2644KV18
Acronyms
Acronym
Document Conventions
Description
Units of Measure
BWS
Byte Write Select
DDR
Double Data Rate
°C
degree Celsius
DLL
Delay Lock Loop
FIT/Dev
failure in time per device
FBGA
Fine-Pitch Ball Grid Array
FIT/Mb
failure in time per mega bit
HSTL
High-Speed Transceiver Logic
MHz
megahertz
I/O
Input/Output
µA
microampere
JTAG
Joint Test Action Group
µs
microsecond
LSB
Least Significant Bit
LSBU
Logical Single-Bit Upsets
LMBU
Logical Multi-Bit Upsets
MSB
Most Significant Bit
ODT
On-Die Termination
PLL
Phase Locked Loop
pF
picofarad
QDR
Quad Data Rate
V
volt
SEL
Single Event Latch-up
W
watt
SRAM
Static Random Access Memory
TAP
Test Access Port
TCK
Test Clock
TDI
Test Data-In
TDO
Test Data-Out
TMS
Test Mode Select
Document Number: 001-44138 Rev. *P
Symbol
Unit of Measure
mA
milliampere
mm
millimeter
ms
millisecond
ns
nanosecond

ohm
%
percent
Page 27 of 30
CY7C2642KV18/CY7C2644KV18
Document History Page
Document Title: CY7C2642KV18/CY7C2644KV18, 144-Mbit QDR® II+ SRAM Two-Word Burst Architecture (2.0 Cycle Read
Latency) with ODT
Document Number: 001-44138
Rev.
ECN
Orig. Of
Change
Submission
Date
**
1980429
VKN /
AESA
See ECN
*A
2557050
VKN /
AESA
09/24/2008
*B
2806011
VKN /
PYRS
11/12/09
Added Neutron Soft Error Immunity.
Updated Capacitance:
Changed Input Capacitance (CIN) from 2 pF to 4 pF.
Changed Output Capacitance (CO) from 3 pF to 4 pF.
Updated Ordering Information:
Included parts that are available.
Added disclaimer at the top of Ordering Information table.
Updated Package Diagram.
*C
2884892
VKN
02/26/10
Updated Switching Characteristics:
Changed minimum value of tSA and tSC parameters from 0.6 ns to 0.4 ns for
200 MHz, from 0.5 ns to 0.35 ns for 250 MHz, and from 0.4 ns to 0.3 ns for
333 MHz and 300 MHz
*D
3024181
NJY
09/07/2010
Changed datasheet status from Preliminary to Final.
Added Ordering Code Definitions under Ordering Information.
Added Acronyms, and Units of Measure.
*E
3242369
NJY
04/27/2011
Updated Switching Characteristics.
Updated to new template.
*F
3275033
NJY
06/06/2011
No technical updates.
*G
3429006
PRIT
12/06/2011
Updated Ordering Information.
Updated Package Diagram.
*H
3599727
AVIA / PRIT
04/25/2012
Updated Features (Removed CY7C2640KV18, CY7C2655KV18,
CY7C2642KV18 related information).
Updated Configurations (Removed CY7C2640KV18, CY7C2655KV18,
CY7C2642KV18 related information).
Updated Functional Description (Removed CY7C2640KV18,
CY7C2655KV18, CY7C2642KV18 related information).
Updated Selection Guide (Removed 250 MHz, 200 MHz frequencies related
information, removed CY7C2640KV18, CY7C2655KV18, CY7C2642KV18
related information).
Removed Logic Block Diagram – CY7C2640KV18.
Removed Logic Block Diagram – CY7C2655KV18.
Removed Logic Block Diagram – CY7C2642KV18.
Updated Pin Configurations (Removed CY7C2640KV18, CY7C2655KV18,
CY7C2642KV18 related information).
Updated Pin Definitions (Removed CY7C2640KV18, CY7C2655KV18,
CY7C2642KV18 related information).
Document Number: 001-44138 Rev. *P
Description Of Change
New data sheet.
Updated Identification Register Definitions:
Changed Revision number [31:29] from 001 to 000.
Updated Power Up Sequence in QDR II+ SRAM:
Updated description.
Updated Figure 4.
Updated Electrical Characteristics:
Updated values of IDD and ISB1 parameters.
Updated Thermal Resistance:
Included values.
Updated to new template.
Page 28 of 30
CY7C2642KV18/CY7C2644KV18
Document History Page (continued)
Document Title: CY7C2642KV18/CY7C2644KV18, 144-Mbit QDR® II+ SRAM Two-Word Burst Architecture (2.0 Cycle Read
Latency) with ODT
Document Number: 001-44138
Rev.
ECN
Orig. Of
Change
Submission
Date
Description Of Change
*H (cont.)
3599727
AVIA / PRIT
04/25/2012
Updated Functional Overview (Removed CY7C2640KV18, CY7C2655KV18,
CY7C2642KV18 related information).
Updated Truth Table (Removed CY7C2640KV18, CY7C2655KV18,
CY7C2642KV18 related information).
Removed Write Cycle Descriptions (Corresponding to CY7C2640KV18,
CY7C2642KV18).
Removed Write Cycle Descriptions (Corresponding to CY7C2655KV18).
Updated Identification Register Definitions (Removed CY7C2640KV18,
CY7C2655KV18, CY7C2642KV18 related information).
Updated Operating Range (Removed Commercial Temperature Range).
Updated Electrical Characteristics (Removed 250 MHz, 200 MHz frequencies
related information, removed CY7C2640KV18, CY7C2655KV18,
CY7C2642KV18 related information).
Updated Switching Characteristics (Removed 250 MHz, 200 MHz frequencies
related information).
*I
3800880
PRIT
11/02/2012
No technical updates.
Completing Sunset Review.
*J
4108422
PRIT
09/02/2013
Updated Features (Included CY7C2642KV18 related information).
Updated Configurations (Included CY7C2642KV18 related information).
Updated Functional Description (Included CY7C2642KV18 related
information).
Updated Pin Configurations (Included CY7C2642KV18 related information).
Updated Pin Definitions (Included CY7C2642KV18 related information).
Updated Functional Overview (Included CY7C2642KV18 related information).
Updated Truth Table (Included CY7C2642KV18 related information).
Included Write Cycle Descriptions (Corresponding to CY7C2642KV18).
Updated Identification Register Definitions (Included CY7C2642KV18 related
information).
Updated Operating Range (Included Commercial Temperature Range).
Updated Electrical Characteristics (Included CY7C2642KV18 related
information).
Updated Ordering Information (Updated part numbers).
Updated to new template.
*K
4234953
PRIT
01/02/2014
No technical updates.
Completing Sunset Review.
*L
4283394
PRIT
02/17/2014
Updated Ordering Information (Updated part numbers).
*M
4372754
PRIT
05/07/2014
Updated Application Example:
Updated Figure 2.
Updated Thermal Resistance:
Updated values of JA parameter.
Included JB parameter and its details.
*N
4575228
PRIT
11/20/2014
Updated Functional Description:
Added “For a complete list of related documentation, click here.” at the end.
Updated Ordering Information:
Updated part numbers.
*O
4829606
PRIT
07/10/2015
Updated Ordering Information:
Updated part numbers.
Updated Package Diagram:
spec 51-85195 – Changed revision from *C to *D.
Updated to new template.
*P
5068841
PRIT
12/31/2015
No technical updates.
Completing Sunset Review.
Document Number: 001-44138 Rev. *P
Page 29 of 30
CY7C2642KV18/CY7C2644KV18
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
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
USB Controllers
Wireless/RF
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, 2008-2015. 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: 001-44138 Rev. *P
Revised December 31, 2015
Page 30 of 30
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.
Similar pages
CY7C2263KV18, CY7C2265KV18 36-Mbit QDR® II+ SRAM Four-Word Burst Architecture (2.5 Cycle Read Latency) with ODT Datasheet.pdf
CYPRESS CY7C2665KV18
CY7C2663KV18, CY7C2665KV18 144-Mbit QDR® II+ SRAM Four-Word Burst Architecture (2.5 Cycle Read Latency) with ODT Datasheet.pdf
CY7C2163KV18/CY7C2165KV18, 18-MBIT QDR® II+ SRAM FOUR-WORD BURST ARCHITECTURE (2.5 CYCLE READ LATENCY) WITH ODT Datasheet.pdf
CYPRESS CY7C2644KV18
CY7C25632KV18, CY7C25652KV18:72-Mbit QDR®II+ SRAM Four-Word Burst Architecture (2.5 Cycle Read Latency) with ODT Datasheet.pdf
CY7C1565KV18 72-Mbit QDR® II+ SRAM Four-Word Burst Architecture (2.5 Cycle Read Latency) Datasheet.pdf
CY7C2168KV18, CY7C2170KV18:18-Mbit DDR II+ SRAM Two-Word Burst Architecture (2.5 Cycle Read Latency) with ODT Datasheet.pdf
CY7C1625KV18, CY7C1612KV18, CY7C1614KV18 144-Mbit QDR® II SRAM Two-Word Burst Architecture Datasheet.pdf
CY7C2670KV18 144-Mbit DDR II+ SRAM Two-Word Burst Architecture (2.5 Cycle Read Latency) with ODT Datasheet.pdf
CY7C1525KV18, CY7C1512KV18, CY7C1514KV18 72-Mbit QDR II SRAM Two-Word Burst Architecture Datasheet.pdf
CYPRESS CY7C1613KV18
CYPRESS CY7C1514KV18
CY7C1312KV18, CY7C1314KV18 18-Mbit QDR® II SRAM Two-Word Burst Architecture Datasheet.pdf
CY7C2268KV18, CY7C2270KV18 36-Mbit DDR II+ SRAM Two-Word Burst Architecture (2.5 Cycle Read Latency) with ODT Datasheet.pdf
CY7C1423KV18/CY7C1424KV18, 36-MBIT DDR II SIO SRAM TWO-WORD BURST ARCHITECTURE Datasheet.pdf
CY7C15632KV18 72-Mbit QDR II+ SRAM Four-Word Burst Architecture (2.5 Cycle Read Latency) Datasheet.pdf
CYPRESS CY7C1625KV18
CY7C1526KV18, CY7C1513KV18, CY7C1515KV18 72-Mbit QDR® II SRAM Four-Word Burst Architecture Datasheet.pdf
CYPRESS CY7C1645KV18
CY7C1143KV18, CY7C1145KV18:18-Mbit QDR® II+ SRAM Four-Word Burst Architecture (2.0 Cycle Read Latency) Datasheet.pdf
CYPRESS CY7C2670KV18