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70V631 - Block Diagram


256K x 18 3.3V Dual-Port RAM, Interleaved I/O's

The 70V631 is a high-speed 256K x 18 Asynchronous Dual-Port Static RAM designed to be used as a stand-alone Dual-Port RAM or as a combination MASTER/ SLAVE Dual-Port RAM for 36-bit-or-more word system. Using the IDT MASTER/SLAVE Dual-Port RAM approach in 36-bit or wider memory system applications results in full-speed, error-free operation without the need for additional discrete logic. An automatic power down feature controlled by the chip enables (either CE0 or CE1) permit the on-chip circuitry of each port to enter a very low standby power mode.


  • Dual-Port allows simultaneous access of the same memory location
  • Dual chip enables allow for depth expansion without external logic
  • Easily expands data bus width to 36 bits or more using the Master/Slave select when cascading more than one device
  • Busy and Interrupt Flags
  • On-chip port arbitration logic
  • Full on-chip hardware support of semaphore signaling between ports Fully asynchronous operation from either port
  • Separate byte controls for multiplexed bus and bus matching compatibility
  • Includes JTAG functionality on BGA package versions only
  • LVTTL-compatible, single 3.3V (±150mV) power supply for core
  • LVTTL-compatible, selectable 3.3V (±150mV)/2.5V (±100mV) power supply for I/Os and control signals on each port
  • Available in a 128-pin TQFP, 208-ball fpBGA and 256-ball BGA
  • Industrial temperature range (–40C to +85C) is available

Product Specification

Core Voltage (V)Bus Width (bits)Density (Kb)Pkg. CodeInterfaceI/O TypeAccess Time (ns)I/O Frequency (MHz)Temp. RangeArchitectureOrganizationFunctionOutput Type
3.3184608PK128, PKG128, BF208, BFG208, BC256, BCG256Async3.3 V LVTTL10, 12, 15-40 to 85°C, 0 to 70°CDual-Port256K x 18Interrupt, JTAG, Master, Slave, Busy

Product Options

Orderable Part IDPart StatusPkg. CodePkg. TypeLead Count (#)Temp. GradePb (Lead) FreeCarrier TypeSample & Buy
70V631S10BCActiveBC256CABGA256CNoTrayCheck Availability
70V631S10BC8ActiveBC256CABGA256CNoReelCheck Availability
70V631S10BCGActiveBCG256CABGA256CYesTrayCheck Availability
70V631S10BCG8ActiveBCG256CABGA256CYesReelCheck Availability
70V631S10BFActiveBF208CABGA208CNoTrayCheck Availability
70V631S10BF8ActiveBF208CABGA208CNoReelCheck Availability
70V631S10BFGActiveBFG208CABGA208CYesTrayCheck Availability
70V631S10BFG8ActiveBFG208CABGA208CYesReelCheck Availability
70V631S10PRFActivePK128TQFP128CNoTrayCheck Availability
70V631S10PRF8ActivePK128TQFP128CNoReelCheck Availability
70V631S10PRFGActivePKG128TQFP128CYesTrayCheck Availability
70V631S12BCActiveBC256CABGA256CNoTrayCheck Availability
70V631S12BC8ActiveBC256CABGA256CNoReelCheck Availability
70V631S12BCIActiveBC256CABGA256INoTrayCheck Availability
70V631S12BCI8ActiveBC256CABGA256INoReelCheck Availability
70V631S12BFActiveBF208CABGA208CNoTrayCheck Availability
70V631S12BF8ActiveBF208CABGA208CNoReelCheck Availability
70V631S12BFGIActiveBFG208CABGA208IYesTrayCheck Availability
70V631S12BFGI8ActiveBFG208CABGA208IYesReelCheck Availability
70V631S12BFIActiveBF208CABGA208INoTrayCheck Availability
70V631S12BFI8ActiveBF208CABGA208INoReelCheck Availability
70V631S12PRFActivePK128TQFP128CNoTrayCheck Availability
70V631S12PRF8ActivePK128TQFP128CNoReelCheck Availability
70V631S12PRFGIActivePKG128TQFP128IYesTrayCheck Availability
70V631S12PRFIActivePK128TQFP128INoTrayCheck Availability
70V631S12PRFI8ActivePK128TQFP128INoReelCheck Availability
70V631S15BCActiveBC256CABGA256CNoTrayCheck Availability
70V631S15BC8ActiveBC256CABGA256CNoReelCheck Availability
70V631S15BFActiveBF208CABGA208CNoTrayCheck Availability
70V631S15BF8ActiveBF208CABGA208CNoReelCheck Availability
70V631S15PRFActivePK128TQFP128CNoTrayCheck Availability
70V631S15PRF8ActivePK128TQFP128CNoReelCheck Availability


Technical Documentation

Title Type Format File Size Datesort icon
Datasheets & Errata
70V631 Data Sheet Datasheet PDF 198 KB Oct 31, 2013
Errata smen-01-03 BUSY timing parameter notcorrect Errata PDF 9 KB Jul 23, 2001
Errata_SMEN-01-04 Jtag timing parameter notcorrect Errata PDF 14 KB Jul 23, 2001
Apps Notes & White Papers
AN-70, Dual-Port Interrupt Expansion Application Note PDF 56 KB May 31, 2006
AN-68, Dual-Port SRAM Simplifies PC-to-TMS320 Interface Application Note PDF 92 KB May 31, 2006
AN-91, The Most Commonly Asked Questions About Async Dual-Ports Application Note PDF 87 KB May 31, 2006
show all (7)
AN-409 DP Memory Simplifies Wireless BaseStation Design Application Note PDF 284 KB May 30, 2006
AN-14, Dual-Port w/ Semaphore Arbitration Application Note PDF 71 KB May 30, 2006
AN-253, Introduction to Multi-Port Memories Application Note PDF 36 KB May 30, 2006
AN-09, Dual-Port SRAMs Yield Bit-Slice Designs Application Note PDF 69 KB May 30, 2006
PCN# : A1606-02 Add Greatek Taiwan as Alternate Assembly Product Change Notice PDF 567 KB Aug 26, 2016
PCN#: A1309-03 Additional Assembly Sources Product Change Notice PDF 398 KB Oct 21, 2013
PCN#: A-0410-02, Change IDT marking logo with new IDT gridless w Product Change Notice PDF 24 KB Nov 14, 2012
show all (17)
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-0607-05 Green Mold Compound KMC3580 for BGA Product Change Notice PDF 194 KB Aug 30, 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-0403-03, BGA package family Product Change Notice PDF 38 KB Dec 9, 2004
PCN#: A-0310-01, Green Products Product Change Notice PDF 26 KB Oct 10, 2003
PCN#:A-0305-02, new m/c G770 & 2300 d/a material Product Change Notice PDF 197 KB Jun 4, 2003
PCN#G-0302-05, New mold compound EME-G700 series Product Change Notice PDF 65 KB Mar 20, 2003
PCN#: G-0302-06, New die attach 3230 from Ablestik Product Change Notice PDF 150 KB Mar 20, 2003
PCN# G-0110-06 REV.1 Mold Compound Product Change Notice PDF 48 KB Apr 26, 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

Software & Tools

Title Type Format File Size Datesort icon
IDT70V631 BSDL Model Model - BSDL ZIP 8 KB May 15, 2007
IDT70V631 Verilog Model Model - Verilog ZIP 10 KB Aug 11, 2003
IDT70V631 IBIS Model Model - IBIS ZIP 44 KB Jul 21, 2004
IDT70V631 VHDL Model Model - VHDL ZIP 5 KB Sep 7, 2004