■ 18-Mbit density (2M x 8, 2M x 9, 1M x 18, 512K x 36)
■ 300 MHz clock for high bandwidth
■ 2-word burst for reducing address bus frequency
■ Double Data Rate (DDR) interfaces
(data transferred at 600 MHz) at 300 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
■ 1.8V core power supply with HSTL inputs and outputs
■ Variable drive HSTL output buffers
■ Expanded HSTL output voltage (1.4V–V
■ Available in 165-Ball FBGA package (13 x 15 x 1.4 mm)
■ Offered in both Pb-free and non Pb-free packages
■ JTAG 1149.1 compatible test access port
■ Delay Lock Loop (DLL) for accurate data placement
DD
)
Configurations
CY7C1392BV18 – 2M x 8
CY7C1992BV18 – 2M x 9
CY7C1393BV18 – 1M x 18
CY7C1394BV18 – 512K x 36
The CY7C1392BV18, CY7C1992BV18, CY7C1393BV18, and
CY7C1394BV18 are 1.8V Synchronous Pipelined SRAMs,
equipped with Double Data Rate Separate IO (DDR-II SIO)
architecture. The DDR-II SIO consists of two separate ports: the
read port and the write port to access the memory array. The
read port has data outputs to support read operations and the
write port has data inputs to support write operations. The DDR-II
SIO has separate data inputs and data outputs to completely
eliminate the need to “turn-around” the data bus required with
common IO devices. Access to each port is accomplished
through a common address bus. 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
is driven on the rising edges of C and C if provided, or on the
rising edge of K and K
location is associated with two 8-bit words in the case of
CY7C1392BV18, two 9-bit words in the case of
CY7C1992BV18, two 18-bit words in the case of
CY7C1393BV18, and two 36-bit words in the case of
CY7C1394BV18 that burst sequentially into or out of the device.
Asynchronous inputs include an output impedance matching
input (ZQ). Synchronous data outputs are tightly matched to the
two output echo clocks CQ/CQ
data separately from each individual DDR-II SIO SRAM in the
system design. Output data clocks (C/C
system clocking and data synchronization flexibility.
All synchronous inputs pass through input registers controlled by
the K or K
registers controlled by the C or C
domain) input clocks. Writes are conducted with on-chip
synchronous self-timed write circuitry.
input clocks. All data outputs pass through output
CInput ClockPositive Input Clock for Output Data. C is used in conjunction with C
Input-
Synchronous
Synchronous
Input-
Synchronous
Synchronous
Outputs-
Synchronous
Synchronous
Data Input Signals. Sampled on the rising edge of K and K clocks during valid write operations.
CY7C1392BV18 - D
CY7C1992BV18 - D
CY7C1393BV18 - D
CY7C1394BV18 - D
[7:0]
[8:0]
[17:0]
[35:0]
Synchronous Load. This input is brought LOW when a bus cycle sequence is defined. This definition
includes address and read/write direction. All transactions operate on a burst of 2 data (one clock period
of bus activity).
Nibble Write Select 0, 1 − Active LOW (CY7C1392BV18 Only). Sampled on the rising edge of the K
and K
clocks during Write operations. Used to select which nibble is written into the device during the
current portion of the Write operations.Nibbles not written remain unaltered.
NWS0 controls D
All Nibble Write Selects are sampled on the same edge as the data. Deselecting a Nibble Write Select
and NWS1 controls D
[3:0]
[7:4]
.
ignores the corresponding nibble of data and it is not written into the device.
Byte Write Select 0, 1, 2 and 3 − Active LOW. Sampled on the rising edge of the K and K clocks during
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.
CY7C1992BV18 − BWS
CY7C1393BV18 − BWS
CY7C1394BV18 − BWS
D
[35:27].
All the Byte Write Selects are sampled on the same edge as the data. Deselecting a Byte Write Select
controls D
0
controls D
0
controls D
0
[8:0]
, BWS1 controls D
[8:0]
, BWS1 controls D
[8:0]
.
[17:9]
,BWS2 controls D
[17:9]
ignores the corresponding byte of data and it is not written into the device.
Address Inputs. Sampled on the rising edge of the K clock during active read and write operations. These
address inputs are multiplexed for both read and write operations. Internally, the device is organized as
2M x 8 (2 arrays each of 1M x 8) for CY7C1392BV18, 2M x 9 (2 arrays each of 1M x 9) for CY7C1992BV18,
1M x 18 (2 arrays each of 512K x 18) for CY7C1393BV18 and 512K x 36 (2 arrays each of 256K x 36)
for CY7C1394BV18. Therefore, only 20 address inputs are needed to access the entire memory array of
CY7C1392BV18 and CY7C1992BV18, 19 address inputs for CY7C1393BV18 and 18 address inputs for
CY7C1394BV18. These inputs are ignored when the appropriate port is deselected.
Data Output Signals. These pins drive out the requested data during a read operation. Valid data is
driven out on the rising edge of both the C and C
clock mode. When the read port is deselected, Q
CY7C1392BV18 − Q
CY7C1992BV18 − Q
CY7C1393BV18 − Q
CY7C1394BV18 − Q
[7:0]
[8:0]
[17:0]
[35:0]
clocks during read operations, or K and K when in single
are automatically tri-stated.
[x:0]
Synchronous Read/Write Input. When LD is LOW, this input designates the access type (read when
R/W
is HIGH, write when R/W is LOW) for the loaded address. R/W must meet the setup and hold times
around the edge of K.
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 on page 9 for further details.
and BWS3 controls
[26:18]
to clock out the read data from
C
Input ClockNegative 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 on page 9 for further details.
KInput ClockPositive Input Clock Input. The rising edge of K is used to capture synchronous inputs to the device
and to drive out data through Q
edge of K.
K
Input ClockNegative Input Clock Input. K is used to capture synchronous inputs being presented to the device and
to drive out data through Q
[x:0]
when in single clock mode. All accesses are initiated on the rising
CQEcho ClockCQ is 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 timings
for the echo clocks is shown in the Switching Characteristics on page 23.
CQ
ZQInputOutput Impedance Matching Inpu t. This input is used to tune the device outputs to the system data bus
DOFF
TDOOutputTDO for JTAG.
TCKInputTCK Pin for JTAG.
TDIInputTDI Pin for JTAG.
TMSInputTMS Pin for JTAG.
NCN/ANot Connected to the Die. Can be tied to any voltage level.
NC/36MN/ANot Connected to the Die. Can be tied to any voltage level.
NC/72MN/ANot Connected to the Die. Can be tied to any voltage level.
NC/144MN/ANot Connected to the Die. Can be tied to any voltage level.
NC/288MN/ANot Connected to the Die. Can be tied to any voltage level.
V
REF
V
DD
V
SS
V
DDQ
Echo ClockCQ is Referenced with Respect to C. This is a free-running clock and is synchronized to the input clock
InputDLL Turn Off − Active LOW . Connecting this pin to ground turns off the DLL inside the device. The timing
Input-
Reference
Power Supply Power Supply Inputs to the Core of the Device.
GroundGround for the Device.
Power Supply Power Supply Inputs for the Outputs of the Device.
for output data (C
for the echo clocks is shown in the Switching Characteristics on page 23.
impedance. CQ, CQ, and Q
between ZQ and ground. Alternatively, this pin can be connected directly to V
minimum impedance mode. This pin cannot be connected directly to GND or left unconnected.
in the DLL turned off operation differs from those listed in this data sheet.
Reference Voltage In put . Static input used to set the reference level for HSTL inputs, Outputs, and AC
measurement points.
) of the DDR-II. In the single clock mode, CQ is generated with respect to K. The timings
output impedance are set to 0.2 x RQ, where RQ is a resistor connected
The CY7C1392BV18, CY7C1992BV18, CY7C1393BV18, and
CY7C1394BV18 are synchronous pipelined Burst SRAMs
equipped with a DDR-II Separate IO interface.
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
when in single clock mode).
All synchronous data inputs (D
controlled by the rising edge of the input clocks (K and K
synchronous data outputs (Q
controlled by the rising edge of the output clocks (C/C
) pass through input registers
[x:0]
) pass through output registers
[x:0]
when in single-clock mode).
All synchronous control (R/W, LD, BWS
input registers controlled by the rising edge of the input clock (K).
) inputs pass through
[0:X]
CY7C1393BV18 is described in the following sections. The
same basic descriptions apply to CY7C1392BV18,
CY7C1992BV18, and CY7C1394BV18.
Read Operations
The CY7C1393BV18 is organized internally as two arrays of
512K x 18. Accesses are completed in a burst of two 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. Following the next K clock rise the
corresponding lowest order 18-bit word of data is driven onto the
Q
using C as the output timing reference. On the subse-
[17:0]
quent rising edge of C, the next 18-bit data word is driven onto
the Q
edge of the output clock (C or C
. The requested data is valid 0.45 ns from the rising
[17:0]
, or K and K when in single clock
mode, for 200 MHz and 250 MHz device). Read accesses can
be initiated on every rising edge of the positive input clock (K).
This pipelines the data flow such that data is transferred out of
the device on every rising edge of the output clocks, C/C (or K/K
when in single clock mode).
The CY7C1393BV18 first completes the pending read transactions, when read access is deselected. Synchronous internal
circuitry automatically tri-states the output following the next
rising edge of the positive output clock (C).
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. On the following K clock rise the data presented
to D
provided BWS
rising edge of the negative input clock (K
presented to D
provided BWS
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). This 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 Write access is deselected, the device ignores all inputs
after the pending write operations are completed.
is latched and stored into the 18-bit write data register,
[17:0]
are both asserted active. On the subsequent
[1:0]
is also stored into the write data register,
[17:0]
are both asserted active. The 36 bits of data
[1:0]
) the information
).
, or K/K
). All
, or K/K
Byte Write Operations
Byte write operations are supported by the CY7C1393BV18. A
write operation is initiated as described in the Write Operations
section. The bytes that are written are determined by BWS0 and
BWS
, which are sampled with each set of 18-bit data words.
1
Asserting the appropriate Byte Write Select input during the data
portion of a write latches the data being presented and writes it
into the device. Deasserting the Byte Write Select input during
the data portion of a write enables the data stored in the device
for that byte to remain unaltered. This feature can be used to
simplify read/modify/write operations to a byte write operation.
Single Clock Mode
The CY7C1393BV18 can be 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. T o use this mode of operation, tie C and C
HIGH at
power on. This function is a strap option and not alterable during
device operation.
DDR Operation
The CY7C1393BV18 enables high-performance operation
through high clock frequencies (achieved through pipelining) and
double data rate mode of operation.
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.
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 V
driver impedance. The value of RQ must be 5x the value of the
to enable the SRAM to adjust its output
SS
intended line impedance driven by the SRAM. The allowable
range of RQ to guarantee impedance matching with a tolerance
of ±15% is between 175Ω and 350Ω
output impedance is adjusted every 1024 cycles at power up to
, with V
=1.5V. The
DDQ
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
with respect to C
. These are free-running clocks and are
synchronized to the output clock of the DDR-II. In the single clock
mode, CQ is generated with respect to K and CQ
with respect to K
These chips use a Delay Lock Loop (DLL) that is designed to
function between 120 MHz and the specified maximum clock
frequency. During power up, when the DOFF is tied HIGH, the
DLL is locked after 1024 cycles of stable clock. The DLL 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 DLL
Application Example
Figure 1 shows four DDR-II SIO used in an application.
Figure 1. Application Example
to lock it to the desired frequency. The DLL automatically locks
1024 clock cycles after a stable clock is presented. The DLL may
be disabled by applying ground to the DOFF
pin. When the DLL
is turned off, the device behaves in DDR-I mode (with one cycle
latency and a longer access time). For information refer to the
application note DLL Considerations in QDRII™/DDRII.
2. X = “Don't Care,” H = Logic HIGH, L = Logic LOW,
↑represents rising edge.
3. Device powers up deselected with the outputs in a tri-state condition.
4. “A” represents address location latched by the devices when transaction was initiated. A + 0, A + 1 represents the internal address 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 respectively 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. It is recommended that K = K
and C = C = HIGH when clock is stopped. This is not essential, but permits most rapid restart by overcoming transmission line charging
symmetrically.
8. Is based on a write cycle that was initiated in accordance with the Write Cycle Descriptions table. NWS
0
, NWS1, BWS0, BWS1, BWS
2 ,
and BWS3 can be altered on
different portions of a write cycle, as long as the setup and hold requirements are achieved.
The truth table for CY7C1392BV18, CY7C1992BV18, CY7C1393BV18, and CY7C1394BV18 follows.
OperationKLDR/WDQDQ
Write Cycle:
L-HLLD(A + 0) at K(t + 1)↑ D(A + 1) at K(t + 1)↑
Load address; wait one cycle;
input write data on consecutive K and K
Read Cycle:
rising edges.
L-HL HQ(A + 0) at C
Load address; wait one and a half cycle;
read data on consecutive C
and C rising edges.
NOP: No OperationL-HHXHigh-ZHigh-Z
Standby: Clock StoppedStoppedXXPrevious StatePrevious State
[2, 3, 4, 5, 6, 7]
(t + 1)↑ Q(A + 1) at C(t + 2)↑
Write Cycle Descriptions
The write cycle description table for CY7C1392BV18 and CY7C1393BV18 follows.
BWS0/
NWS
0
BWS1/
NWS
K
1
K
Comments
LLL–H–During the data portion of a write sequence:
CY7C1392BV18 − both nibbles (D
CY7C1393BV18 − both bytes (D
) are written into the device.
[7:0]
) are written into the device.
[17:0]
LL–L-H During the data portion of a write sequence:
CY7C1392BV18 − both nibbles (D
CY7C1393BV18 − both bytes (D
) are written into the device.
[7:0]
) are written into the device.
[17:0]
LHL–H–During the data portion of a write sequence:
CY7C1392BV18 − only the lower nibble (D
CY7C1393BV18 − only the lower byte (D
[3:0]
) is written into the device, D
[8:0]
LH–L–H During the data portion of a write sequence:
CY7C1392BV18 − only the lower nibble (D
CY7C1393BV18 − only the lower byte (D
[3:0]
) is written into the device, D
[8:0]
HLL–H–During the data portion of a write sequence:
CY7C1392BV18 − only the upper nibble (D
CY7C1393BV18 − only the upper byte (D
[7:4]
[17:9]
HL–L–H During the data portion of a write sequence :
CY7C1392BV18 − only the upper nibble (D
CY7C1393BV18 − only the upper byte (D
[7:4]
[17:9]
HHL–H–No data is written into the devices during this portion of a write operation.
[2, 8]
) is written into the device, D
) is written into the device, D
) is written into the device, D
) is written into the device, D
) is written into the device, D
) is written into the device, D
remains unaltered.
[7:4]
remains unaltered.
[17:9]
remains unaltered.
[7:4]
remains unaltered.
[17:9]
remains unaltered.
[3:0]
remains unaltered.
[8:0]
remains unaltered.
[3:0]
remains unaltered.
[8:0]
HH–L–H No data is written into the devices during this portion of a write operation.
Document #: 38-05623 Rev. *DPage 10 of 31
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