CY7C1522AV18, CY7C1529AV18
CY7C1523AV18, CY7C1524AV18
Document #: 001-06981 Rev. *D Page 10 of 30
Truth Table
The truth table for CY7C1522AV18, CY7C1529AV18, CY7C1523AV18, and CY7C1524AV18 follows. [2, 3, 4, 5, 6, 7]
Operation KLD R/W DQ DQ
Write Cycle:
Load address; wait one cycle;
input write data on consecutive K and K rising edges.
L-H L L D(A + 0) at K(t + 1)↑D(A + 1) at K(t + 1)↑
Read Cycle:
Load address; wait one and a half cycle;
read data on consecutive C and C rising edges.
L-H L H Q(A + 0) at C(t + 1)↑Q(A + 1) at C(t + 2)↑
NOP: No Operation L-H H X High-Z High-Z
Standby: Clock Stopped Stopped X X Previous State Previous State
Write Cycle Descriptions
The write cycle description table for CY7C1522AV18 and CY7C1523AV18 follows. [2, 8]
BWS0/
NWS0
BWS1/
NWS1KKComments
L L L–H – During the data portion of a write sequence :
CY7C1522AV18 − both nibbles (D[7:0]) are written into the device,
CY7C1523AV18 − both bytes (D[17:0]) are written into the device.
L L – L-H During the data portion of a write sequence :
CY7C1522AV18 − both nibbles (D[7:0]) are written into the device,
CY7C1523AV18 − both bytes (D[17:0]) are written into the device.
L H L–H – During the data portion of a write sequence :
CY7C1522AV18 − only the lower nibble (D[3:0]) is written into the device, D[7:4] remains unaltered.
CY7C1523AV18 − 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 :
CY7C1522AV18 − only the lower nibble (D[3:0]) is written into the device, D[7:4] remains unaltered.
CY7C1523AV18 − 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 :
CY7C1522AV18 − only the upper nibble (D[7:4]) is written into the device, D[3:0] remains unaltered.
CY7C1523AV18 − 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 :
CY7C1522AV18 − only the upper nibble (D[7:4]) is written into the device, D[3:0] remains unaltered.
CY7C1523AV18 − 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 + 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. 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. Is based on a write cycle that was initiated in accordance with the Write Cycle Descriptions table. NWS0, NWS1, BWS0, BWS1, BWS2 and BWS3 can be altered on
different portions of a write cycle, as long as the setup and hold requirements are achieved.
[+] Feedback [+] Feedback