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72235 - Block Diagram


2K x 18 SyncFIFO, 5.0V

The 72235 is a 2K x 18 First-In, First-Out memory with clocked read and write controls and would be useful for a wide variety of data buffering needs, such as optical disk controllers, Local Area Networks (LANs), and interprocessor communication. These FIFOs have 18-bit input and output ports. The read clock can be tied to the write clock for single clock operation or the two clocks can run asynchronous of one another for dual-clock operation. These devices are depth expandable using a Daisy-Chain technique.


  • 10 ns read/write cycle time
  • Empty and Full flags signal FIFO status
  • Easy expandable in depth and width
  • Asynchronous or coincident read and write clocks
  • Programmable Almost-Empty and Almost-Full flags with default settings
  • Half-Full flag capability
  • Dual-Port zero fall-through time architecture
  • Output enable puts output data bus in high-impedance state
  • Available in 64-pin TQFP, STQFP and 68-pin PLCC packages
  • Industrial temperature range (–40C to +85C) is available

Product Specification

Core Voltage (V)Bus Width (bits)Density (Kb)Pkg. CodeInterfaceI/O TypeI/O Frequency (MHz)Cycle Time (ns)OrganizationTemp. RangeArchitectureAccess Time (ns)
51836PP64, PL68, PPG64, PN64, PNG64, PLG68Synchronous5.0 V TTL40.00, 66.00, 100.002K x 18-40 to 85°C, 0 to 70°CUni-directional

Product Options

Orderable Part IDPart StatusPkg. CodePkg. TypeLead Count (#)Temp. GradePb (Lead) FreeCarrier TypeSample & Buy
72235LB10JActivePL68PLCC68CNoTubeCheck Availability
72235LB10J8ActivePL68PLCC68CNoReelCheck Availability
72235LB10JGNot Recommended
PLG68PLCC68CYesTubeCheck Availability
72235LB10JG8Not Recommended
PLG68PLCC68CYesReelCheck Availability
72235LB10PFActivePN64TQFP64CNoTrayCheck Availability
72235LB10PF8ActivePN64TQFP64CNoReelCheck Availability
72235LB10PFGActivePNG64TQFP64CYesTrayCheck Availability
72235LB10PFG8ActivePNG64TQFP64CYesReelCheck Availability
72235LB10TFActivePP64TQFP64CNoTrayCheck Availability
72235LB10TF8ActivePP64TQFP64CNoReelCheck Availability
72235LB10TFGActivePPG64TQFP64CYesTrayCheck Availability
72235LB10TFG8ActivePPG64TQFP64CYesReelCheck Availability
72235LB15JActivePL68PLCC68CNoTubeCheck Availability
72235LB15J8ActivePL68PLCC68CNoReelCheck Availability
72235LB15JIActivePL68PLCC68INoTubeCheck Availability
72235LB15JI8ActivePL68PLCC68INoReelCheck Availability
72235LB15PFActivePN64TQFP64CNoTrayCheck Availability
72235LB15PF8ActivePN64TQFP64CNoReelCheck Availability
72235LB15PFGIActivePNG64TQFP64IYesTrayCheck Availability
72235LB15PFGI8ActivePNG64TQFP64IYesReelCheck Availability
72235LB15PFIActivePN64TQFP64INoTrayCheck Availability
72235LB15PFI8ActivePN64TQFP64INoReelCheck Availability
72235LB15TFActivePP64TQFP64CNoTrayCheck Availability
72235LB15TF8ActivePP64TQFP64CNoReelCheck Availability
72235LB15TFGIActivePPG64TQFP64IYesTrayCheck Availability
72235LB15TFGI8ActivePPG64TQFP64IYesReelCheck Availability
72235LB15TFINot Recommended
PP64TQFP64INoTrayCheck Availability
72235LB15TFI8Not Recommended
PP64TQFP64INoReelCheck Availability
72235LB25JActivePL68PLCC68CNoTubeCheck Availability
72235LB25J8ActivePL68PLCC68CNoReelCheck Availability
72235LB25JIActivePL68PLCC68INoTubeCheck Availability
72235LB25JI8ActivePL68PLCC68INoReelCheck Availability
72235LB25PFActivePN64TQFP64CNoTrayCheck Availability
72235LB25PF8ActivePN64TQFP64CNoReelCheck Availability
72235LB25PFIActivePN64TQFP64INoTrayCheck Availability
72235LB25PFI8ActivePN64TQFP64INoReelCheck Availability
72235LB25TFActivePP64TQFP64CNoTrayCheck Availability
72235LB25TF8ActivePP64TQFP64CNoReelCheck Availability
72235LB25TFINot Recommended
PP64TQFP64INoTrayCheck Availability
72235LB25TFI8Not Recommended
PP64TQFP64INoReelCheck Availability


Technical Documentation

Title Type Format File Size Datesort icon
Datasheets & Errata
72205LB-72245LB Data Sheet Datasheet PDF 333 KB Mar 22, 2013
Apps Notes & White Papers
AN-83: Width Expansion of SyncFIFOs Application Note PDF 73 KB Jul 31, 2006
AN-60: Designing with the IDT SyncFIFO . . . Application Note PDF 312 KB May 12, 2006
PCN# : A1606-02 Add Greatek Taiwan as Alternate Assembly Product Change Notice PDF 567 KB Aug 26, 2016
PCN# : A1602-01(R1) Add Greatek Taiwan as Alternate Assembly Product Change Notice PDF 611 KB Apr 14, 2016
PCN# : A1602-01 Add Greatek Taiwan as Alternate Assembly Product Change Notice PDF 611 KB Feb 15, 2016
show all (24)
PCN# : TB1504-01R1 Qty per Reel Standardization for Selective Packages Product Change Notice PDF 95 KB Oct 22, 2015
PCN# : TB1504-01 Qty per Reel Standardization for Selective Packages Product Change Notice PDF 50 KB Jul 21, 2015
PCN# : TB1304-01 Change of Moisture Sensitive Level on Selective Products Product Change Notice PDF 129 KB May 13, 2013
PCN#: A-0410-02, Change IDT marking logo with new IDT gridless w Product Change Notice PDF 24 KB Nov 14, 2012
PCN# : A-0610-02 ASAT China as Alternate Facility for CABGA/CVBGA/FPBGA/TQFP/PQFP Product Change Notice PDF 252 KB Oct 19, 2006
PCN# A-0607-06 MMT Thailand as Alternate Assembly Facility for PLCC, SOIC 150mil/300mil Product Change Notice PDF 223 KB Oct 6, 2006
A-0603-04 Transfer TQFP and PQFP from ASAT HK to ASAT China Product Change Notice PDF 164 KB May 10, 2006
PCN#: TB-0512-01 Reel Color Changed from Blue to Black Product Change Notice PDF 729 KB Dec 16, 2005
PCN A-0506-03; Packing Material Change Product Change Notice PDF 290 KB Jul 19, 2005
PCN#: A-0412-04 - To comply with Pb-free labels - Green Products Product Change Notice PDF 80 KB Dec 14, 2004
PCN#: A-0310-01, Green Products Product Change Notice PDF 26 KB Oct 10, 2003
PCN#: A-0309-04, new mold compound G600 material Product Change Notice PDF 134 KB Oct 7, 2003
PCN#: G-0302-06, New die attach 3230 from Ablestik Product Change Notice PDF 150 KB Mar 20, 2003
PCN#G-0302-05, New mold compound EME-G700 series Product Change Notice PDF 65 KB Mar 20, 2003
PCN# G-0206-08, Orientation of square PQFP & TQFP Product Change Notice PDF 150 KB Jun 17, 2002
PCN# F0202-04R1: Wafer Fabrication Site Change Product Change Notice PDF 50 KB Jun 1, 2002
PCN# G-0110-06 REV.1 Mold Compound Product Change Notice PDF 48 KB Apr 26, 2002
PCN# G-0203-05 Mold Compound Product Change Notice PDF 40 KB Apr 16, 2002
PCN# G-0110-06 Mold Compound Product Change Notice PDF 47 KB Dec 14, 2001
PCN# G0106-01, Moisture Sensitive Label Change Product Change Notice PDF 274 KB Jun 11, 2001
PCN# G9911-05, To qualify low alpha mold compound. Product Change Notice PDF 44 KB Nov 18, 1999

Software & Tools

Title Type Format File Size Datesort icon
72235 HSPICE Model - HSPICE application/x-tar 32 KB Jun 29, 1999
72235 IBIS Model - IBIS ZIP 10 KB Jun 29, 1999