PRELIMINARY
CY7C1410V18
CY7C1425V18
CY7C1412V18
CY7C1414V18
Document #: 38-05592 Rev. **
Page 6 of 23
Pin Definitions
Pin Name
I/O
Pin Description
D[x:0]
Input-
Synchronous
Data input signals, sampled on the rising edge of K and K clocks during valid write
operations.
CY7C1410V18 - D[7:0]
CY7C1425V18 - D[8:0]
CY7C1412V18 - D[17:0]
CY7C1414V18 - D[35:0]
WPS
Input-
Synchronous
Write Port Select, active LOW. Sampled on the rising edge of the K clock. When
asserted active, a Write operation is initiated. Deasserting will deselect the Write port.
Deselecting the Write port will cause D[x:0] to be ignored.
NWS0,NWS1
Nibble Write Select 0, 1
− active LOW. (CY7C1425V18 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[3:0] and NWS1 controls D[7:4]. All Nibble Write Selects
are sampled on the same edge as the data. Deselecting a Nibble Write Select will cause
the corresponding nibble of data to be ignored and not written into the device.
BWS0, BWS1,
BWS2, BWS3
Input-
Synchronous
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.
CY7C1425V18
− BWS
0 controls D[8:0]
CY7C1412V18
− BWS
0 controls D[8:0], BWS1 controls D[17:9].
CY7C1414V18
− BWS
0 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 will cause the corresponding byte of data to be ignored and not written into
the device.
A
Input-
Synchronous
Address Inputs. Sampled on the rising edge of the K (Read address) and K (Write
address) clocks during active Read and Write operations. These address inputs are
multiplexed for both Read and Write operations. Internally, the device is organized as 4M
x 8 (2 arrays each of 2M x 8) for CY7C1410V18, 4M x 9 (2 arrays each of 2M x 9) for
CY7C1425V18, 2M x 18 (2 arrays each of 1M x 18) for CY7C1412V18 and 2M x 36 (2
arrays each of 512K x 36) for CY7C1414V18. Therefore, only 21 address inputs are
needed to access the entire memory array of CY7C1410V18 and CY7C1425V18, 20
address inputs for CY7C1412V18 and 19 address inputs for CY7C1414V18. These
inputs are ignored when the appropriate port is deselected.
Q[x:0]
Outputs-
Synchronous
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 clocks during Read
operations or K and K when in single clock mode. When the Read port is deselected,
Q[x:0] are automatically three-stated.
CY7C1410V18
− Q
[7:0]
CY7C1425V18
− Q
[8:0]
CY7C1412V18
− Q
[17:0]
CY7C1414V18
− Q
[35:0]
RPS
Input-
Synchronous
Read Port Select, active LOW. Sampled on the rising edge of Positive Input Clock (K).
When active, a Read operation is initiated. Deasserting will cause the Read port to be
deselected. When deselected, the pending access is allowed to complete and the output
drivers are automatically three-stated following the next rising edge of the C clock. Each
read access consists of a burst of two sequential transfers.
C
Input-
Clock
Positive Output Clock Input. 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 Output Clock Input. 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.