Cypress CY7C1514KV18 Manual De Usuario

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CY7C1510KV18, CY7C1525KV18
CY7C1512KV18, CY7C1514KV18
Document Number: 001-00436 Rev. *E
Page 10 of 30
Truth Table
The truth table for CY7C1510KV18, CY7C1525KV18, CY7C1512KV18, and CY7C1514KV18 follow. 
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 + 0) at K(t) 
D(A + 1) at K(t) 
Read Cycle:
Load address on the rising edge of K; 
wait one and a half cycle; read data on C and C rising edges.
L-H
L
X
Q(A + 0) at C(t + 1) 
↑ Q(A + 1) at C(t + 2) ↑
NOP: No Operation
L-H
H
H
D = X
Q = High-Z
D = X
Q = High-Z 
Standby: Clock Stopped
Stopped
X
X
Previous State
Previous State
Write Cycle Descriptions 
The write cycle description table for CY7C1510KV18 and CY7C1512KV18 follow. 
 
BWS
0
/
NWS
0
BWS
1
/
NWS
1
K
K
Comments
L
L
L–H
During the data portion of a write sequence 
CY7C1510KV18 
− both nibbles (D
[7:0]
) are written into the device.
CY7C1512KV18 
− both bytes (D
[17:0]
) are written into the device.
L
L
L-H During the data portion of a write sequence 
:
CY7C1510KV18 
− both nibbles (D
[7:0]
) are written into the device.
CY7C1512KV18 
− both bytes (D
[17:0]
) are written into the device.
L
H
L–H
During the data portion of a write sequence 
:
CY7C1510KV18 
− only the lower nibble (D
[3:0]
) is written into the device, D
[7:4]
 remains unaltered. 
CY7C1512KV18 
− only the lower byte (D
[8:0]
) is written into the device, D
[17:9]
 remains unaltered.
L
H
L–H During the data portion of a write sequence 
CY7C1510KV18 
− only the lower nibble (D
[3:0]
) is written into the device, D
[7:4]
 remains unaltered.
CY7C1512KV18 
− only the lower byte (D
[8:0]
) is written into the device, D
[17:9]
 remains unaltered.
H
L
L–H
During the data portion of a write sequence 
CY7C1510KV18 
− only the upper nibble (D
[7:4]
) is written into the device, D
[3:0]
 remains unaltered.
CY7C1512KV18 
− only the upper byte (D
[17:9]
) is written into the device, D
[8:0]
 remains unaltered.
H
L
L–H During the data portion of a write sequence 
CY7C1510KV18 
− only the upper nibble (D
[7:4]
) is written into the device, D
[3:0]
 remains unaltered.
CY7C1512KV18 
− only the upper byte (D
[17:9]
) is written into the device, D
[8:0]
 remains unaltered.
H
H
L–H
No data is written into the devices during this portion of a write operation. 
H
H
L–H No data is written into the devices during this portion of a write operation. 
Notes
2. X = “Don't Care,” H = Logic HIGH, L = Logic LOW, 
represents rising edge.
3. Device powers up deselected with the outputs in a tristate 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. Ensure that when the clock is stopped K = K and C = C = HIGH. 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 
 table. NWS
0
, NWS
1
,
 
BWS
0
, BWS
1
,
 
BWS
2
,
 
and BWS
can be altered on 
different portions of a write cycle, as long as the setup and hold requirements are achieved.