CY7C1311CV18, CY7C1911CV18
CY7C1313CV18, CY7C1315CV18
Document Number: 001-07165 Rev. *C
Page 10 of 31
Application Example
Figure 1 shows four QDR-II used in an application.
Figure 1. Application Example
Truth Table
The truth table for CY7C1311CV18, CY7C1911CV18, CY7C1313CV18, and CY7C1315CV18 follows. [2, 3, 4, 5, 6, 7]
Operation
K
RPS WPS
DQ
DQ
DQ
DQ
Write Cycle:
Load address on the rising
edge of K; write data on
two consecutive K and K
rising edges.
L-H
H [8]
L [9] 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
L [9]
XQ(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
R = 250
ohms
Vt
R
R = 250
ohms
Vt
Vt
R
Vt = Vddq/2
R = 50
ohms
R
CC#
D
A
SRAM #4
R
P
S
#
W
P
S
#
B
W
S
#
K
ZQ
CQ/CQ#
Q
K#
CC#
D
A
K
SRAM #1
R
P
S
#
W
P
S
#
B
W
S
#
ZQ
CQ/CQ#
Q
K#
BUS
MASTER
(CPU
or
ASIC)
DATA IN
DATA OUT
Address
RPS#
WPS#
BWS#
Source K
Source K#
Delayed K
Delayed K#
CLKIN/CLKIN#
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.
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