72255LA20TF IDT, 72255LA20TF Datasheet - Page 17

• Manufacturer Part Number: 72255LA20TF
• Description: FIFO
• Manufacturer: IDT

Specifications of 72255LA20TF

• Part # Aliases: IDT72255LA20TF

Q
NOTES:
1. t
2. LD = HIGH, OE = LOW, EF = HIGH
D
Q
NOTES:
1. t
2. LD = HIGH.
3. First word latency: 60ns + t
IDT72255LA/72265LA CMOS SuperSync FIFO™
8,192 x 18 and 16,384 x 18
D
WCLK
RCLK
WCLK
0
0
0
0
RCLK
rising edge of the RCLK and the rising edge of the WCLK is less than t
WEN
rising edge of WCLK and the rising edge of RCLK is less than t
SKEW1
- Q
- D
REN
SKEW3
- D
- Q
FF
n
n
n
n
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 t
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 t
t
ENS
t
DATA IN OUTPUT REGISTER
ENS
t
t
OLZ
SKEW1
t
ENH
t
REF
t
REF
A
Figure 8. Read Cycle, Empty Flag and First Data Word Latency Timing (IDT Standard Mode)
t
OE
(1)
+ 1*
TRCLK
t
t
SKEW3
ENH
t
ENS
t
DS
t
A
.
D
(1)
1
0
NO WRITE
Figure 7. Write Cycle and Full Flag Timing (IDT Standard Mode)
NO OPERATION
t
t
DHS
ENH
LAST WORD
1
SKEW3
2
t
WFF
, then EF deassertion may be delayed one extra RCLK cycle.
SKEW1
t
t
DS
OHZ
t
t
DS
t
ENS
CLKH
, then the FF deassertion may be delayed one extra WCLK cycle.
D
D
1
X
NO OPERATION
t
WFF
t
t
17
ENH
DATA READ
DH
t
t
DH
CLK
2
t
CLKL
t
CLKH
t
t
REF
ENS
t
OLZ
t
SKEW1
t
CLK
(1)
t
CLKL
t
ENS
t
ENH
LAST WORD
t
A
1
NO WRITE
t
ENH
t
A
COMMERCIAL AND INDUSTRIAL
WFF
2
REF
TEMPERATURE RANGES
). If the time between the
). If the time between the
NEXT DATA READ
t
t
ENS
WFF
JANUARY 13, 2009
t
DS
D
0
D
X
+1
t
REF
t
t
4670 drw10
ENH
A
t
DH
t
WFF
4670 drw 11
D
1