Cypress CY7C1516AV18 Manual De Usuario

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CY7C1516AV18, CY7C1527AV18
CY7C1518AV18, CY7C1520AV18
Document Number: 001-06982 Rev. *D
Page 6 of 30
Pin Definitions 
Pin Name
IO
Pin Description
DQ
[x:0]
Input Output-
Synchronous
Data Input Output Signals. Inputs are sampled on the rising edge of K and K clocks during valid write 
operations. These pins drive out the requested data when the read operation is active. Valid data is driven 
out on the rising edge of both the C and C clocks during read operations or K and K when in single clock 
mode. When read access is deselected, Q
[x:0]
 are automatically tri-stated.
CY7C1516AV18 
− DQ
[7:0]
CY7C1527AV18 
− DQ
[8:0]
CY7C1518AV18 
− DQ
[17:0]
CY7C1520AV18 
− DQ
[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.
NWS
0
NWS
1
Input-
Synchronous
Nibble Write Select 0, 1 
 Active LOW (CY7C1516AV18 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
0
 controls D
[3:0] 
and NWS
1
 controls D
[7:4]
.
All the 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.
CY7C1527AV18 
− BWS
0
 controls D
[8:0] 
CY7C1518AV18
 − BWS
0
 controls D
[8:0]
 and BWS
1
 controls D
[17:9].
CY7C1520AV18
 − 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, A0
Input-
Synchronous
Address Inputs. 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 CY7C1516AV18 and 8M x 9 (2 arrays each 
of 4M x9) for CY7C1527AV18, 4M x 18 (2 arrays each of 2M x 18) for CY7C1518AV18, and 2M x 36 (2 
arrays each of 1M x 36) for CY7C1520AV18.
CY7C1516AV18 – Since the least significant bit of the address internally is a “0,” only 22 external address 
inputs are needed to access the entire memory array. 
CY7C1527AV18 – Since the least significant bit of the address internally is a “0,” only 22 external address 
inputs are needed to access the entire memory array. 
CY7C1518AV18 – A0 is the input to the burst counter. These are incremented in a linear fashion internally. 
22 address inputs are needed to access the entire memory array.
CY7C1520AV18 – A0 is the input to the burst counter. These are incremented in a linear fashion internally. 
21 address inputs are needed to access the entire memory array. All the address inputs are ignored when 
the appropriate port is deselected. 
R/W
Input-
Synchronous
Synchronous Read or 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 loaded address. R/W must meet the setup and hold times 
around edge of K.
C
Input Clock
Positive Input Clock for Output Data. C is used in conjunction with C to clock out the read data from 
the device. C and C can be used together to deskew the flight times of various devices on the board back 
to the controller. See application example for further details.
C
Input Clock
Negative Input Clock for Output Data. C is used in conjunction with C to clock out the read data from 
the device. C and C can be used together to deskew the flight times of various devices on the board back 
to the controller. See application example for further details.
K
Input Clock
Positive Input Clock Input. The rising edge of K is used to capture synchronous inputs to the device 
and to drive out data through Q
[x:0] 
when in single clock mode. All accesses are initiated on the rising 
edge of K. 
K
Input Clock
Negative Input Clock Input. K is used to capture synchronous data being presented to the device and 
to drive out data through Q
[x:0]
 when in single clock mode.