IDT72V255LA/72V265LA 3.3 VOLT CMOS SuperSync FIFO™
8,192 x 18, 16,384 x 18
COMMERCIAL AND INDUSTRIAL
TEMPERATURE RANGES
DESCRIPTION (CONTINUED)
•
•
The period required by the retransmit operation is now fixed and short.
The first word data latency period, from the time the first word is written to
an empty FIFO to the time it can be read, is now fixed and short. (The variable
clock cycle counting delay associated with the latency period found on
previous SuperSync devices has been eliminated on this SuperSync
family.)
SuperSync FIFOs are particularly appropriate for networking, video,
telecommunications, data communications and other applications that need to
buffer large amounts of data.
The input port is controlled by a Write Clock (WCLK) input and a Write Enable
(WEN) input. Data is written into the FIFO on every rising edge of WCLK when
WEN
is asserted. The output port is controlled by a Read Clock (RCLK) input
and Read Enable (REN) input. Data is read from the FIFO on every rising
edge of RCLK when
REN
is asserted. An Output Enable (OE) input is provided
for three-state control of the outputs.
The frequencies of both the RCLK and the WCLK signals may vary from 0
to fMAX with complete independence. There are no restrictions on the
frequency of one clock input with respect to the other.
PIN CONFIGURATIONS
WCLK
PRS
LD
FWFT/SI
GND
EF/OR
RCLK
REN
RT
OE
FF/IR
MRS
PAF
HF
V
CC
PAE
PIN 1
64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49
WEN
SEN
DC
(1)
V
CC
GND
D17
D16
D15
D14
D13
D12
D11
D10
D9
D8
D7
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
Q17
Q16
GND
Q15
Q14
V
CC
Q13
Q12
Q11
GND
Q10
Q9
Q8
Q7
Q6
GND
GND
Q0
Q1
GND
Q2
Q3
V
CC
Q4
Q5
D1
D0
D5
D4
D3
D2
D6
4672 drw 02
TQFP (PN64-1, ORDER CODE: PF)
STQFP (PP64-1, ORDER CODE: TF)
TOP VIEW
NOTE:
1. DC = Don’t Care. Must be tied to GND or V
CC
, cannot be left open.
2