IDT72255LA15PFG IDT, Integrated Device Technology Inc, IDT72255LA15PFG Datasheet - Page 4

• Manufacturer Part Number: IDT72255LA15PFG
• Description: IC FIFO SUPERSYNC 8KX18 64QFP
• Manufacturer: IDT, Integrated Device Technology Inc
• Series: 7200r

Specifications of IDT72255LA15PFG

• Function: Synchronous
• Memory Size: 144K (8K x 18)
• Access Time: 15ns
• Voltage - Supply: 4 V ~ 5.5 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 64-TQFP, 64-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Rate: -
• Other names: 72255LA15PFG; 800-1500

PIN DESCRIPTION
IDT72255LA/72265LA CMOS SuperSync FIFO™
8,192 x 18 and 16,384 x 18
Symbol
D
MRS
PRS
RT
FWFT/SI
WCLK
WEN
RCLK
REN
OE
SEN
LD
DC
FF/IR
EF/OR
PAF
PAE
Q
V
GND
HF
0
CC
0
–D
–Q
17
17
Name
Data Inputs
Master Reset
Partial Reset
Retransmit
First Word Fall
Through/Serial In
Write Clock
Write Enable
Read Clock
Read Enable
Output Enable
Serial Enable
Load
Don't Care
Full Flag/
Input Ready
Empty Flag/
Output Ready
Programmable
Almost-Full Flag
Programmable
Almost-Empty Flag
Half-Full Flag
Data Outputs
Power
Ground
I/O
O
O
O
O
O
O
I
I
I
I
I
I
I
I
I
I
I
I
I
Data inputs for a 18-bit bus.
MRS initializes the read and write pointers to zero and sets the output register to all zeroes. During
Master Reset, the FIFO is configured for either FWFT or IDT Standard mode, one of two program
mable flag default settings, and serial or parallel programming of the offset settings.
PRS initializes the read and write pointers to zero and sets the output register to all zeroes. During
Partial Reset, the existing mode (IDT or FWFT), programming method (serial or parallel), and
programmable flag settings are all retained.
RT asserted on the rising edge of RCLK initializes the READ pointer to zero, sets the EF flag to
LOW (OR to HIGH in FWFT mode) temporarily and does not disturb the write pointer, programming
method, existing timing mode or programmable flag settings. RT is useful to reread data from the first
physical location of the FIFO.
During Master Reset, selects First Word Fall Through or IDT Standard mode. After Master Reset,
this pin functions as a serial input for loading offset registers.
When enabled by WEN, the rising edge of WCLK writes data into the FIFO and offsets into the
programmable registers for parallel programming, and when enabled by SEN, the rising edge of
WCLK writes one bit of data into the programmable register for serial programming.
WEN enables WCLK for writing data into the FIFO memory and offset registers.
When enabled by REN, the rising edge of RCLK reads data from the FIFO memory and offsets from
REN enables RCLK for reading data from the FIFO memory and offset registers.
OE controls the output impedance of Q
SEN enables serial loading of programmable flag offsets.
During Master Reset, LD selects one of two partial flag default offsets (127 or 1,023) and determines
the flag offset programming method, serial or parallel. After Master Reset, this pin enables writing to
and reading from the offset registers.
This pin must be tied to either V
In the IDT Standard mode, the FF function is selected. FF indicates whether or not the FIFO
memory is full. In the FWFT mode, the IR function is selected. IR indicates whether or not
there is space available for writing to the FIFO memory.
In the IDT Standard mode, the EF function is selected. EF indicates whether or not the FIFO
memory is empty. In FWFT mode, the OR function is selected. OR indicates whether or not there is
valid data available at the outputs.
PAF goes LOW if the number of words in the FIFO memory is more than total word capacity of the
FIFO minus the full offset value m, which is stored in the Full Offset register. There are two possible
default values for m: 127 or 1,023.
PAE goes LOW if the number of words in the FIFO memory is less than offset n, which is stored in
the Empty Offset register. There are two possible default values for n: 127 or 1,023. Other values
for n can be programmed into the device.
HF indicates whether the FIFO memory is more or less than half-full.
Data outputs for an 18-bit bus.
+5 Volt power supply pins.
Ground pins.
the programmable registers.
4
CC
or GND and must not toggle after Master Reset.
Description
n.
COMMERCIAL AND INDUSTRIAL
TEMPERATURE RANGES
JANUARY 13, 2009