Cypress CY7C1176V18 Manual De Usuario

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CY7C1161V18, CY7C1176V18
CY7C1163V18, CY7C1165V18
Document Number: 001-06582 Rev. *D
Page 10 of 29
Application Example
 shows four QDR-II+ used in an application.
Figure 1. Application Example
Truth Table 
The truth table for the CY7C1161V18, CY7C1176V18, CY7C1163V18, and CY7C1165V18 follows.
Operation
K
RPS WPS
DQ
DQ
DQ
DQ
Write Cycle: Load 
address on rising edge of 
K; input write data on two 
consecutive K and K rising 
edges.
L-H
H
L
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 (2.5 Cycle 
Latency): Load address on 
rising edge of K; wait one 
and a half cycle; read data 
on two consecutive K and 
K rising edges.
L-H
L
X
Q(A) at K(t + 2) 
↑ Q(A + 1) at K(t + 3) ↑ Q(A + 2) at K(t + 3)↑ Q(A + 3) at K(t + 4) ↑
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
BUS  MASTER
(CPU or ASIC)
DATA IN
DATA OUT
Address
Source K
Source K
Vt
Vt
Vt
R
R
CLKIN/CLKIN
D
A
K
SRAM #4
RQ = 250ohms
ZQ
CQ/CQ
Q
K
RPS WPS BWS
D
A
K
SRAM #1
RQ = 250ohms
ZQ
CQ/CQ
Q
K
RPS WPS BWS
RPS
WPS
BWS
R = 50ohms, Vt = V        /2
DDQ
R
Notes
2. The above application shows four QDR-II+ being used.
3. X = “Don't Care,” H = Logic HIGH, L = Logic LOW, 
↑ 
represents rising edge.
4. Device powers up deselected and the outputs in a tri-state condition.
5. “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.
6. “t” represents the cycle at which a read or write operation is started. t + 1, t + 2, t + 3 and t + 4 are the first, second, third, and fourth clock cycles, respectively succeeding 
the “t” clock cycle.
7. Data inputs are registered at K and K rising edges. Data outputs are delivered on K and K rising edges.
8. It is recommended that K = K = HIGH when clock is stopped. This is not essential, but permits most rapid restart by overcoming transmission line charging symmetrically.
9. If this signal was LOW to initiate the previous cycle, this signal becomes a “Don’t Care” for this operation.
10. 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.