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CY7C4255, CY7C4265, CY7C4265A
Document #: 38-06004 Rev. *E
Page 8 of 23
Figure 5. Reset Timing[17]
Figure 6. First Data Word Latency after Reset with Simultaneous Read and Write
Notes
17. The clocks (RCLK, WCLK) can be free-running during reset.
18. After reset, the outputs are LOW if OE = 0 and three-state if OE = 1.
19. When tSKEW2 > minimum specification, tFRL (maximum) = tCLK + tSKEW2. When tSKEW2 < minimum specification, tFRL (maximum) = either 2*tCLK + tSKEW2 or
tCLK + tSKEW2. The Latency Timing applies only at the Empty Boundary (EF = LOW).
20. The first word is available the cycle after EF goes HIGH, always.
Switching Waveforms (continued)
tRS
tRSR
Q0–Q17
RS
tRSF
tRSF
tRSF
OE = 1
OE = 0
REN,WEN,
LD
EF,PAE
FF,PAF,
HF
[18]
D0 (FIRSTVALIDWRITE)
tSKEW2
WEN
WCLK
Q0 –Q17
EF
REN
OE
tOE
tENS
tOLZ
tDS
RCLK
tREF
tA
tFRL
D1
D2
D3
D4
D0
D1
D0 –D17
tA
[19]
[20]
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