IDT72255LA IDT [Integrated Device Technology], IDT72255LA Datasheet - Page 27

• Manufacturer Part Number: IDT72255LA
• Description: CMOS SUPERSYNC FIFO
• Manufacturer: IDT [Integrated Device Technology]

COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGE
© 2001 Integrated Device Technology, Inc
“LA” mark. The LA part is pin-for-pin compatible with the original “L” version. Some differences exist between the two versions.
The following table details these differences.
NOTES:
1.
2.
3.
4.
5.
Integrated Device Technology, Inc.
IDT has improved the performance of the IDT72255/72265 SuperSync™ FIFOs. The new versions are designated by the
WCLK and RCLK can vary independently and can be stopped. There is no restriction on operating WCLK and RCLK.
This is t
Tf is the period of the ‘selected clock’.
T
Typical I
C
RCLK
L
= Capacitive Load (in pF).
Pin #3
First Word Latency
(IDT Standard Mode)
First Word Latency
(FWFT Mode)
Retransmit Latency
(IDT Standard Mode)
Retransmit Latency
(FWFT Mode)
I
I
Typical I
CC1
CC2
is the cycle period of the read clock.
SKEW3
CC1
DIFFERENCES BETWEEN THE IDT72255LA/72265LA AND IDT72255L/72265L
is based on V
CC1
.
Ite m
5
CC
= 5V, t
DC (Don’t Care) - There
is no restriction on
WCLK and RCLK. See
note 1.
60ns
60ns
60ns
60ns
80mA
20mA
15 + 2.1*f
(mA)
A
=25 C, f
2
2
2
2
NE W P ART
+ t
+ t
+ t
+ t
7 2 2 5 5 LA
7 2 2 6 5 LA
REF
REF
REF
REF
CMOS SUPERSYNC FIFO™
8,192 x 18
16,384 x 18
S
S
= WCLK frequency = RCLK frequency (in MHz using TTL levels), data switching at f
+ 0.02*C
+ 1 T
+ 2 T
+ 1 T
+ 2 T
RCLK
RCLK
RCLK
RCLK
L
*f
4
4
4
4
S
FS (Frequency Select)
t
t
t
t
180mA
15mA
Not Given
FWL1
FWL2
RTF1
RTF2
=14*Tf
=14*Tf
=10*Tf
=10*Tf
O LD P ART
7 2 2 5 5 L
7 2 2 6 5 L
ADDENDUM
3
3
3
3
+ 3T
+ 4T
+ 2T
+ 3T
RCLK
RCLK
RCLK
RCLK
4
4
4
4
(ns) Retransmit latency in the LA
(ns) Retransmit latency in the LA
(ns) First word latency in the LA
(ns) First word latency in the LA
In the LA part this pin must
be tied to either V
and must not toggle after
reset.
part is a fixed value,
independent of the
frequency of RCLK or
WCLK.
part is a fixed value,
independent of the
frequency of RCLK or WCLK
part is a fixed value,
independent of the
frequency of RCLK or WCLK
part is a fixed value,
independent of the
frequency of RCLK or WCLK
Active supply current
Standby current
Typical I
calculation.
CC1
Comme nts
Current
PRELIMINARY
CC
IDT72255LA
IDT72265LA
or GND
S
/2,
APRIL 2001
1