IDT72421/72201/72211/72221/72231/72241 CMOS SyncFIFO
MILITARY AND COMMERCIAL TEMPERATURE RANGES
64 x 9, 256 x 9, 512 x 9, 1024 x 9, 2048 x 9 and 4096 x 9CMOS SyncFIFO
IDT72421
IDT72201
IDT72211
IDT72221
IDT72231
IDT72241
64 X 9, 256 x 9, 512 x 9,
1024 X 9, 2048 X 9 and 4096 x 9
Integrated Device Technology, Inc.
FEATURES:
• 64 x 9-bit organization (IDT72421)
• 256 x 9-bit organization (IDT72201)
• 512 x 9-bit organization (IDT72211)
• 1024 x 9-bit organization (IDT72221)
• 2048 x 9-bit organization (IDT72231)
• 4096 x 9-bit organization (IDT72241)
Out (FIFO) memories with clocked read and write controls.
The IDT72421/72201/72211/72221/72231/72241 have a 64,
256, 512, 1024, 2048, and 4096 x 9-bit memory array,
respectively. These FIFOs are applicable for a wide variety of
data buffering needs such as graphics, local area networks
and interprocessor communication.
These FIFOs have 9-bit input and output ports. The input
port is controlled by a free-running clock (WCLK), and two
write enable pins (WEN1, WEN2). Data is written into the
Synchronous FIFO on every rising clock edge when the write
enable pins are asserted. The output port is controlled by
another clock pin (RCLK) and two read enable pins (REN1,
REN2). The read clock can be tied to the write clock for single
clockoperationorthetwoclockscanrunasynchronousofone
another for dual-clock operation. An output enable pin (OE) is
provided on the read port for three-state control of the output.
The Synchronous FIFOs have two fixed flags, Empty (EF)
and Full (FF). Two programmable flags, Almost-Empty (PAE)
and Almost-Full (PAF), are provided for improved system
control. TheprogrammableflagsdefaulttoEmpty+7andFull-
7 for PAE and PAF, respectively. The programmable flag
offset loading is controlled by a simple state machine and is
initiated by asserting the load pin (LD).
• 12 ns read/write cycle time (IDT72421/72201/72211)
• 15 ns read/write cycle time (IDT72221/72231/72241)
• Read and write clocks can be independent
• Dual-Ported zero fall-through time architecture
• Empty and Full flags signal FIFO status
• Programmable Almost-Empty and Almost-Full flags can
be set to any depth
• Programmable Almost-Empty and Almost-Full flags
default to Empty+7, and Full-7, respectively
• Output enable puts output data bus in high-impedance
state
• Advanced submicron CMOS technology
• Available in 32-pin plastic leaded chip carrier (PLCC),
ceramic leadless chip carrier (LCC), and 32-pin Thin
Quad Flat Pack (TQFP)
• For Through-Hole product please see the IDT72420/
72200/72210/72220/72230/72240 data sheet
• Military product compliant to MIL-STD-883, Class B
The IDT72421/72201/72211/72221/72231/72241 are
fabricated using IDT’s high-speed submicron CMOS
technology. Military grade product is manufactured in
compliance with the latest revision of MIL-STD-883, Class B.
DESCRIPTION:
The IDT72421/72201/72211/72221/72231/72241
SyncFIFO are very high-speed, low-power First-In, First-
FUNCTIONAL BLOCK DIAGRAM
D0 - D8
WCLK
LD
WEN1
WEN2
INPUT REGISTER
OFFSET REGISTER
EF
FLAG
LOGIC
PAE
PAF
FF
WRITE CONTROL
LOGIC
RAM ARRAY
64 x 9, 256 x 9,
512 x 9, 1024 x 9,
2048 x 9, 4096 x 9
WRITE POINTER
READ POINTER
READ CONTROL
LOGIC
OUTPUT REGISTER
RESET LOGIC
RS
RCLK
REN1
REN2
OE
2655 drw 01
Q0 - Q8
SyncFIFO is a trademark and the IDT logo is a registered trademark of Integrated Device Technology, Inc.
MILITARY AND COMMERCIAL TEMPERATURE RANGES
DECEMBER 1995
1996 Integrated Device Technology, Inc
DSC-2655/6
For latest information contact IDT's web site at www.idt.com or fax-on-demand at 408-492-8391. 5.07
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