Cypress CY7C1415BV18 Manual De Usuario

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CY7C1411BV18, CY7C1426BV18
CY7C1413BV18, CY7C1415BV18
Document Number: 001-07037 Rev. *D
Page 10 of 30
Truth Table
The truth table for CY7C1411BV18, CY7C1426BV18, CY7C1413BV18, and CY7C1415BV18 follows. 
Operation
K
RPS WPS
DQ
DQ
DQ
DQ
Write Cycle:
Load address on the rising 
edge of K; input write data 
on two consecutive K and 
K rising edges.
L-H
D(A) at K(t + 1)
↑ D(A + 1) at K(t + 1)↑ D(A + 2) at K(t + 2)↑ D(A + 3) at K(t + 2)↑
Read Cycle:
Load address on the rising 
edge of K; wait one and a 
half cycle; read data on 
two consecutive C and C 
rising edges.
L-H
X
Q(A)  at  C(t + 1)
↑ Q(A + 1) at C(t + 2)↑ Q(A + 2) at C(t + 2)↑ Q(A + 3) at C(t + 3)↑
NOP: No Operation
L-H
H
H
D = X
Q = High-Z
D = X
Q = High-Z 
D = X
Q = High-Z
D = X
Q = High-Z
Standby: Clock Stopped
Stopped
X
X
Previous State
Previous State
Previous State
Previous State
Write Cycle Descriptions 
The write cycle description table for CY7C1411BV18 and CY7C1413BV18 follows. 
 
BWS
0
/
NWS
0
BWS
1
/
NWS
1
K
K
Comments
L
L
L–H
During the data portion of a write sequence 
CY7C1411BV18 
− both nibbles (D
[7:0]
) are written into the device, 
CY7C1413BV18 
− both bytes (D
[17:0]
) are written into the device.
L
L
L-H During the data portion of a write sequence 
:
CY7C1411BV18 
− both nibbles (D
[7:0]
) are written into the device,
CY7C1413BV18 
− both bytes (D
[17:0]
) are written into the device.
L
H
L–H
During the data portion of a write sequence 
:
CY7C1411BV18 
− only the lower nibble (D
[3:0]
) is written into the device, D
[7:4]
 remains unaltered. 
CY7C1413BV18 
− 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 
CY7C1411BV18 
− only the lower nibble (D
[3:0]
) is written into the device, D
[7:4]
 remains unaltered.
CY7C1413BV18 
− 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 
CY7C1411BV18 
− only the upper nibble (D
[7:4]
) is written into the device, D
[3:0]
 remains unaltered.
CY7C1413BV18 
− 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 
CY7C1411BV18 
− only the upper nibble (D
[7:4]
) is written into the device, D
[3:0]
 remains unaltered.
CY7C1413BV18 
− 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 tri-state condition.
4. “A” represents address location latched by the devices when transaction was initiated. A + 1, A + 2, and A +3 represents the address sequence in the burst.
5. “t” represents the cycle at which a read/write operation is started. t + 1, t + 2, and t + 3 are the first, second and third 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. If this signal was LOW to initiate the previous cycle, this signal becomes a “Don’t Care” for this operation.
9. This signal was HIGH on previous K clock rise. Initiating consecutive read or write operations on consecutive K clock rises is not permitted. The device ignores the 
second read or write request.
10. 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
3
 can be altered on 
different portions of a write cycle, as long as the setup and hold requirements are achieved.