17
COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES
IDT72V295/72V2105 3.3V HIGH DENSITY CMOS
SUPERSYNC FIFOTM 131,072 x 18, 262,144 x 18
Figure 8. Read Cycle, Empty Flag and First Data Word Latency Timing (IDT Standard Mode)
NOTES:
1. tSKEW1 is the minimum time between a rising WCLK edge and a rising RCLK edge to guarantee that
EF will go HIGH (after one RCLK cycle plus tREF). If the time between the rising edge
of WCLK and the rising edge of RCLK is less than tSKEW1, then
EF deassertion may be delayed one extra RCLK cycle.
2.
LD = HIGH.
3. First word latency: tSKEW1 + 1*TRCLK + tREF.
NOTES:
1. tSKEW1 is the minimum time between a rising RCLK edge and a rising WCLK edge to guarantee that
FF will go high (after one WCLK cycle pus tWFF). If the time between the rising
edge of the RCLK and the rising edge of the WCLK is less than tSKEW1, then the
FF deassertion may be delayed one extra WCLK cycle.
2.
LD = HIGH, OE = LOW, EF = HIGH.
Figure 7. Write Cycle and Full Flag Timing (IDT Standard Mode)
D0 - Dn
WEN
RCLK
REN
tENH
Q0 - Qn
DATA READ
NEXT DATA READ
DATA IN OUTPUT REGISTER
tSKEW1(1)
4668 drw 10
WCLK
NO WRITE
1
2
1
2
tDS
NO WRITE
tWFF
tA
tENS
tSKEW1(1)
tDS
tA
DX
tDH
tCLK
tCLKH
tCLKL
DX+1
tWFF
tDH
FF
RCLK
REN
4668 drw 11
EF
tCLK
tCLKH
tCLKL
tENH
tREF
tA
tOLZ
tOE
Q0 - Qn
OE
WCLK
tSKEW1(1)
WEN
D0 - Dn
tENS
tENH
tDS
tDHS
D0
1
2
tOLZ
LAST WORD
D0
D1
tENS
tENH
tDS
tDH
tOHZ
LAST WORD
tREF
tENH
tENS
tA
tREF
tENS
tENH
NO OPERATION