72245LB25JI IDT, 72245LB25JI Datasheet - Page 10

• Manufacturer Part Number: 72245LB25JI
• Description: FIFO
• Manufacturer: IDT

Specifications of 72245LB25JI

• Number Of Circuits: 2
• Data Bus Width: 18 bit
• Bus Direction: Unidirectional
• Memory Size: 72 KB
• Timing Type: Synchronous
• Organization: 4 K x 18
• Maximum Clock Frequency: 40 MHz
• Access Time: 15 ns
• Supply Voltage - Max: 5.5 V
• Supply Voltage - Min: 4.5 V
• Maximum Operating Current: 60 mA
• Maximum Operating Temperature: + 85 C
• Package / Case: PLCC-64
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Part # Aliases: IDT72245LB25JI

NOTE:
1. t
NOTES:
1. When t
2. The first word is available the cycle after EF goes HIGH, always.
IDT72205LB/72215LB/72225LB/72235LB/72245LB CMOS SyncFIFO
256 x 18, 512 x 18, 1,024 x 18, 2,048 x 18 and 4,096 x 18
Q
D
Q
D
edge of RCLK and the rising edge of WCLK is less than t
0
0
WCLK
RCLK
SKEW1
The Latency Timing applies only at the Empty Boundary (EF = LOW).
WCLK
0
0
- Q
RCLK
- D
- Q
- D
17
17
SKEW2
is the minimum time between a rising RCLK edge and a rising WCLK edge to guarantee that FF will go HIGH during the current clock cycle. If the time between the rising
17
17
LOW
DATA IN OUTPUT REGISTER
t
minimum specification, t
ENS
t
ENS
t
SKEW1
t
NO WRITE
DS
(1)
Figure 7. First Data Word Latency after Reset with Simultaneous Read and Write
FRL
D
t
0
(maximum) = t
ENH
(first valid write)
t
A
t
SKEW2
t
WFF
CLK
SKEW1
t
OLZ
+ t
, then FF may not change state until the next WCLK edge.
SKEW2
t
DS
t
FRL
Figure 8. Full Flag Timing
. When t
(1)
D
DATA WRITE
1
t
SKEW2
REF
t
t
ENS
WFF
10
< minimum specification, t
TM
t
DATA READ
OE
t
ENS
D
t
A
t
2
SKEW1
NO WRITE
FRL
(1)
(maximum) = either 2*t
t
ENH
D
t
COMMERCIAL AND INDUSTRIAL
A
0
D
t
A
t
3
TEMPERATURE RANGES
CLK
WFF
NEXT DATA READ
+ t
SKEW2
t
MARCH 2013
DS
or t
2766 drw 10
CLK
D
1
2766 drw 09
DATA
WRITE
D
+ t
4
SKEW2
.