The 723656 is a 2K x 36 x 2 Triple Bus sync FIFO memory has two independent dual-port SRAM FIFOs on board each chip that can buffer data between a bidirectional 36-bit bus and two unidirectional 18-bit buses. FIFO data can be read and written using either 18-bit or 9-bit formats with a choice of Big- or Little-Endian configurations. Communication between each port may bypass the FIFOs via two mailbox registers. This device can operate in the IDT Standard mode or the first word fall through mode.


  • Clock frequencies up to 83 MHz (8ns access time)
  • Two independent FIFOs buffer data between one bidirectional 36-bit port and two unidirectional 18-bit ports
  • 18-bit (word) and 9-bit (byte) bus sizing of 18 bits (word)
  • Programmable Almost-Empty and Almost-Full flags
  • Serial or parallel programming of partial flags
  • Loopback mode on Port A
  • Retransmit Capability
  • Master Reset clears data and configures FIFO, Partial Reset clears data but retains configuration settings
  • Mailbox bypass registers for each FIFO
  • Free-running CLKA, CLKB and CLKC may be asynchronous or coincident
  • Auto power down minimizes power dissipation
  • Available in 128-pin TQFP package
  • Pin compatible to the lower density parts, 7236x6
  • Industrial temperature range (–40C to +85C) is available

Product Options

Orderable Part ID Part Status Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
Obsolete 128 C No Tray
Obsolete 128 C No Reel
Obsolete 128 C No Tray
Obsolete 128 C No Reel

Documentation & Downloads

Title Other Languages Type Format File Size Date
Datasheets & Errata
723656-723676 Datasheet Datasheet PDF 689 KB
User Guides & Manuals
Cypress Discontinued Dual-port and FIFO to IDT Cross Reference Guide Guide PDF 123 KB
PDN# : FS-13-01 PRODUCT DISCONTINUANCE NOTICE Product Discontinuation Notice PDF 86 KB
PCN#: A-0410-02, Change IDT marking logo with new IDT gridless w Product Change Notice PDF 24 KB
A-0603-04 Transfer TQFP and PQFP from ASAT HK to ASAT China Product Change Notice PDF 164 KB
PCN A-0506-03; Packing Material Change Product Change Notice PDF 290 KB
PCN#: A-0412-04 - To comply with Pb-free labels - Green Products Product Change Notice PDF 80 KB
PCN#: A-0310-01, Green Products Product Change Notice PDF 26 KB
PCN#G-0302-05, New mold compound EME-G700 series Product Change Notice PDF 65 KB
PCN#: G-0302-06, New die attach 3230 from Ablestik Product Change Notice PDF 150 KB
PCN# G-0110-06 REV.1 Mold Compound Product Change Notice PDF 48 KB
PCN# G-0110-06 Mold Compound Product Change Notice PDF 47 KB
PCN# G0106-01, Moisture Sensitive Label Change Product Change Notice PDF 274 KB
F-01-01 Obsolescence of Selected Speed Grades Product Delete Notice PDF 31 KB
PCN# G9911-05, To qualify low alpha mold compound. Product Change Notice PDF 44 KB