3.3 VOLT CMOS SuperSync FIFO™
32,768 x 18
65,536 x 18
IDT72V275
IDT72V285
Slim Thin Quad Flat Pack (STQFP)
FEATURES:
• High-performance submicron CMOS technology
Industrial temperature range (-40°C to +85°C) is available
• Choose among the following memory organizations:
•
IDT72V275
IDT72V285
32,768 x 18
65,536 x 18
DESCRIPTION:
• Pin-compatible with the IDT72V255/72V265 SuperSync FIFOs
• 10ns read/write cycle time (6.5ns access time)
• Fixed, low first word data latency time
• Auto power down minimizes standby power consumption
• Master Reset clears entire FIFO
• Partial Reset clears data, but retains programmable
settings
• Retransmit operation with fixed, low first word data
latency time
• Empty, Full and Half-Full flags signal FIFO status
• Programmable Almost-Empty and Almost-Full flags, each flag can
default to one of two preselected offsets
• Program partial flags by either serial or parallel means
• Select IDT Standard timing (using EF and FF flags) or First Word
Fall Through timing (using OR and IR flags)
The IDT72V275/72V285 are exceptionally deep, high speed, CMOS
First-In-First-Out (FIFO) memories with clocked read and write controls.
These FIFOs offer numerous improvements over previous SuperSync
FIFOs, includingthe following:
• Thelimitationofthefrequencyofoneclockinputwithrespecttotheother
has beenremoved. TheFrequencySelectpin(FS)has beenremoved,
thusitisnolongernecessarytoselectwhichofthetwoclockinputs,RCLK
or WCLK, is running at the higher frequency.
• The period required by the retransmit operation is now fixed and short.
• Thefirstworddatalatencyperiod,fromthetimethefirstwordiswrittento
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
SuperSyncfamily.)
•
Output enable puts data outputs into high impedance state
• Easily expandable in depth and width
• Independent Read and Write clocks (permit reading and writing
simultaneously)
SuperSyncFIFOsareparticularlyappropriatefornetwork,video,telecom-
munications,datacommunicationsandotherapplicationsthatneedtobuffer
largeamountsofdata.
• Available in the 64-pin Thin Quad Flat Pack (TQFP) and the 64-pin
FUNCTIONAL BLOCK DIAGRAM
D0 -D17
WEN
WCLK
LD
SEN
OFFSET REGISTER
INPUT REGISTER
FF/IR
PAF
EF/OR
PAE
FLAG
LOGIC
WRITE CONTROL
LOGIC
HF
FWFT/SI
RAM ARRAY
32,768 x 18
65,536 x 18
WRITE POINTER
READ POINTER
READ
CONTROL
LOGIC
RT
OUTPUT REGISTER
MRS
PRS
RESET
LOGIC
RCLK
REN
4512 drw 01
Q0 -Q17
OE
IDTandtheIDTlogoaretrademarksofIntegratedDeviceTechnology, Inc. TheSuperSyncFIFOisatrademarkofIntegratedDeviceTechnology, Inc.
COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES
APRIL 2001
1
DSC-4512/2
2001 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to change without notice.