STK12C68-5 (SMD5962-94599)
Document Number: 001-51026 Rev. **
Page 10 of 18
SRAM Write Cycle
Parameter
Description
35 ns
55 ns
Unit
Min
Max
Min
Max
Cypress
Parameter
Alt
t
WC
t
AVAV
Write Cycle Time
35
55
ns
t
PWE
t
WLWH,
t
WLEH
Write Pulse Width
25
45
ns
t
SCE
t
ELWH,
t
ELEH
Chip Enable To End of Write
25
45
ns
t
SD
t
DVWH,
t
DVEH
Data Setup to End of Write
12
25
ns
t
HD
t
WHDX,
t
EHDX
Data Hold After End of Write
0
0
ns
t
AW
t
AVWH,
t
AVEH
Address Setup to End of Write
25
45
ns
t
SA
t
AVWL,
t
AVEL
Address Setup to Start of Write
0
0
ns
t
HA
t
WHAX,
t
EHAX
Address Hold After End of Write
0
0
ns
t
HZWE
[9,10]
t
WLQZ
Write Enable to Output Disable
13
15
ns
t
LZWE
[9]
t
WHQX
Output Active After End of Write
5
5
ns
Switching Waveforms
Figure 10. SRAM Write Cycle 1: WE Controlled
[11, 12]
Figure 11. SRAM Write Cycle 2: CE Controlled
[11, 12]
t
WC
t
SCE
t
HA
t
AW
t
SA
t
PWE
t
SD
t
HD
t
HZWE
t
LZWE
ADDRESS
CE
WE
DATA IN
DATA OUT
DATA VALID
HIGH IMPEDANCE
PREVIOUS DATA
t
WC
ADDRESS
t
SA
t
SCE
t
HA
t
AW
t
PWE
t
SD
t
HD
CE
WE
DATA IN
DATA OUT
HIGH IMPEDANCE
DATA VALID
Notes
10. If WE is Low when CE goes Low, the outputs remain in the high impedance state.
11. HSB must be high during SRAM Write cycles.
12. CE or WE must be greater than V
IH
during address transitions.
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