Cypress CY7C1524AV18 Manual De Usuario

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CY7C1522AV18, CY7C1529AV18
CY7C1523AV18, CY7C1524AV18
Document #: 001-06981 Rev. *D
Page 6 of 30
Pin Definitions 
Pin Name
IO
Pin Description
D
[x:0]
Input-
Synchronous
Data Input Signals. Sampled on the rising edge of K and K clocks during valid write operations. 
CY7C1522AV18 - D
[7:0]
CY7C1529AV18 - D
[8:0]
CY7C1523AV18 - D
[17:0]
CY7C1524AV18 - D
[35:0]
LD
Input-
Synchronous
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).
NWS
0
NWS
1
Nibble Write Select 0, 1 
 Active LOW (CY7C1522AV18 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. 
NWS
controls D
[3:0] 
and NWS
1
 controls D
[7:4]
All Nibble Write Selects are sampled on the same edge as the data. Deselecting a Nibble Write Select 
ignores the corresponding nibble of data and it is not written into the device.
BWS
0
BWS
1
BWS
2
BWS
3
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.
CY7C1529AV18
 − BWS
0
 controls D
[8:0]
 
CY7C1523AV18
 − BWS
0
 controls D
[8:0]
, BWS
1
 controls D
[17:9]
.
CY7C1524AV18
 − BWS
0
 controls D
[8:0]
, BWS
1
 controls D
[17:9]
,BWS
2
 controls D
[26:18]
 and BWS
3
 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
Input-
Synchronous
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 
8M x 8 (2 arrays each of 4M x 8) for CY7C1522AV18, 8M x 9 (2 arrays each of 4M x 9) for CY7C1529AV18, 
4M x 18 (2 arrays each of 2M x 18) for CY7C1523AV18 and 2M x 36 (2 arrays each of 1M x 36) for 
CY7C1524AV18. Therefore, only 22 address inputs are needed to access the entire memory array of 
CY7C1522AV18 and CY7C1529AV18, 21 address inputs for CY7C1523AV18 and 20 address inputs for 
CY7C1524AV18. 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 tri-stated. 
CY7C1522AV18 
− Q
[7:0]
CY7C1529AV18 
− Q
[8:0]
CY7C1523AV18 
− Q
[17:0]
CY7C1524AV18 
− Q
[35:0]
R/W
Input-
Synchronous
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.
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 
 on page 9 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 
 on page 9 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 inputs being presented to the device and 
to drive out data through Q
[x:0]
 when in single clock mode.