Write cycle descriptions – Cypress CY7C1157V18 User Manual
Page 10
CY7C1146V18, CY7C1157V18
CY7C1148V18, CY7C1150V18
Document Number: 001-06621 Rev. *D
Page 10 of 27
Write Cycle Descriptions
The write cycle descriptions of CY7C1146V18 and CY7C1148V18 follows.
BWS
0
/
NWS
0
BWS
1
/
NWS
1
K
K
Comments
L
L
L – H
–
When the Data portion of a write sequence is active
:
CY7C1146V18
− both nibbles (D
[7:0]
) are written into the device.
CY7C1148V18
− both bytes (D
[17:0]
) are written into the device.
L
L
–
L – H When the Data portion of a write sequence is active
:
CY7C1146V18
− both nibbles (D
[7:0]
) are written into the device.
CY7C1148V18
− both bytes (D
[17:0]
) are written into the device.
L
H
L – H
–
When the Data portion of a write sequence is active
:
CY7C1146V18
− only the lower nibble (D
[3:0]
) is written into the device, D
[7:4]
remains unaltered.
CY7C1148V18
− only the lower byte (D
[8:0]
) is written into the device, D
[17:9]
remains unaltered.
L
H
–
L – H When the Data portion of a write sequence is active
:
CY7C1146V18
− only the lower nibble (D
[3:0]
) is written into the device, D
[7:4]
remains unaltered.
CY7C1148V18
− only the lower byte (D
[8:0]
) is written into the device, D
[17:9]
remains unaltered.
H
L
L – H
–
When the Data portion of a write sequence is active:
CY7C1146V18
− only the upper nibble (D
[7:4]
) is written into the device, D
[3:0]
remains unaltered.
CY7C1148V18
− only the upper byte (D
[17:9]
) is written into the device, D
[8:0]
remains unaltered.
H
L
–
L – H When the Data portion of a write sequence is active
:
CY7C1146V18
− only the upper nibble (D
[7:4]
) is written into the device, D
[3:0]
remains unaltered.
CY7C1148V18
− 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 when this portion of a write operation is active.
H
H
–
L – H No data is written into the devices when this portion of a write operation is active.
The write cycle descriptions of CY7C1146V18 follows.
BWS
0
K
K
Comments
L
L – H
–
When the Data portion of a write sequence is active
, the single byte (D
[8:0]
) is written into the device.
L
–
L – H
When the Data portion of a write sequence is active
, the single byte (D
[8:0]
) is written into the device.
H
L – H
–
No data is written into the device when this portion of a write operation is active.
H
–
L – H
No data is written into the device when this portion of a write operation is active.
Note
9. Is based on a Write cycle was initiated in accordance with the Write Cycle Description Truth Table. Alter BWS
0
, BWS
1
, BWS
2
,
and BWS
3
on different portions of a Write
cycle, as long as the setup and hold requirements are achieved.