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70T651 - Block Diagram


256K x 36 Async, 3.3V/2.5V Dual-Port RAM, Interleaved I/O's

The 70T651 is a high-speed 256K x 36 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 72-bit-or-more word system which would result 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
  • RapidWrite Mode simplifies high-speed consecutive write cycles
  • Dual chip enables allow for depth expansion without external logic
  • Easily expands data bus width to 72 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
  • Sleep Mode Inputs on both ports
  • Includes JTAG functionality
  • Single 2.5V (±100mV) 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 256-ball BGA, 208-pin PQFP and 208-ball fpBGA.
  • 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
2.5369216DR208, BC256, BF208, BFG208Async2.5 V LVTTL, 3.3 V LVTTL8, 10, 12, 15-40 to 85°C, 0 to 70°CDual-Port256K x 36Busy, Sleep Mode, Interrupt, JTAG, Semaphore, Master, Slave

Product Options

Orderable Part IDPart StatusPkg. CodePkg. TypeLead Count (#)Temp. GradePb (Lead) FreeCarrier TypeSample & Buy
70T651S10BCActiveBC256CABGA256CNoTrayCheck Availability
70T651S10BC8ActiveBC256CABGA256CNoReelCheck Availability
70T651S10BCIActiveBC256CABGA256INoTrayCheck Availability
70T651S10BCI8ActiveBC256CABGA256INoReelCheck Availability
70T651S10BFActiveBF208CABGA208CNoTrayCheck Availability
70T651S10BF8ActiveBF208CABGA208CNoReelCheck Availability
70T651S10BFGActiveBFG208CABGA208CYesTrayCheck Availability
70T651S10BFG8ActiveBFG208CABGA208CYesReelCheck Availability
70T651S10BFGIActiveBFG208CABGA208IYesTrayCheck Availability
70T651S10BFGI8ActiveBFG208CABGA208IYesReelCheck Availability
70T651S10BFIActiveBF208CABGA208INoTrayCheck Availability
70T651S10BFI8ActiveBF208CABGA208INoReelCheck Availability
70T651S10DRActiveDR208PQFP208CNoTrayCheck Availability
70T651S12BCActiveBC256CABGA256CNoTrayCheck Availability
70T651S12BC8ActiveBC256CABGA256CNoReelCheck Availability
70T651S12BCIActiveBC256CABGA256INoTrayCheck Availability
70T651S12BCI8ActiveBC256CABGA256INoReelCheck Availability
70T651S12BFActiveBF208CABGA208CNoTrayCheck Availability
70T651S12BF8ActiveBF208CABGA208CNoReelCheck Availability
70T651S12BFGIActiveBFG208CABGA208IYesTrayCheck Availability
70T651S12BFGI8ActiveBFG208CABGA208IYesReelCheck Availability
70T651S12BFIActiveBF208CABGA208INoTrayCheck Availability
70T651S12BFI8ActiveBF208CABGA208INoReelCheck Availability
70T651S12DRActiveDR208PQFP208CNoTrayCheck Availability
70T651S12DRIActiveDR208PQFP208INoTrayCheck Availability
70T651S15BCActiveBC256CABGA256CNoTrayCheck Availability
70T651S15BC8ActiveBC256CABGA256CNoReelCheck Availability
70T651S15BFActiveBF208CABGA208CNoTrayCheck Availability
70T651S15BF8ActiveBF208CABGA208CNoReelCheck Availability
70T651S15DRActiveDR208PQFP208CNoTrayCheck Availability
70T651S8BCObsoleteBC256CABGA256CNoTrayCheck Availability
70T651S8BC8ObsoleteBC256CABGA256CNoReelCheck Availability
70T651S8BFObsoleteBF208CABGA208CNoTrayCheck Availability
70T651S8BF8ObsoleteBF208CABGA208CNoReelCheck Availability
70T651S8BFGObsoleteBFG208CABGA208CYesTrayCheck Availability
70T651S8BFG8ObsoleteBFG208CABGA208CYesReelCheck Availability


Technical Documentation

Title Type Format File Size Datesort icon
Datasheets & Errata
70T651/9 Data Sheet Datasheet PDF 739 KB Jul 22, 2015
Apps Notes & White Papers
AN-70, Dual-Port Interrupt Expansion Application Note PDF 56 KB May 31, 2006
AN-91, The Most Commonly Asked Questions About Async Dual-Ports Application Note PDF 87 KB May 31, 2006
AN-59, Using 7024/7025 DP SRAMs to Match System Bus Widths Application Note PDF 89 KB May 31, 2006
show all (6)
AN-14, Dual-Port w/ Semaphore Arbitration Application Note PDF 71 KB May 30, 2006
AN-409 DP Memory Simplifies Wireless BaseStation Design Application Note PDF 284 KB May 30, 2006
AN-253, Introduction to Multi-Port Memories Application Note PDF 36 KB May 30, 2006
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
PCN# A-0607-05 Green Mold Compound KMC3580 for BGA Product Change Notice PDF 194 KB Aug 30, 2006
show all (10)
PCN#: TB-0512-01 Reel Color Changed from Blue to Black Product Change Notice PDF 729 KB Dec 16, 2005
PCN# A-0506-01: New m/c G700 & d/a 8361J for PQFP Product Change Notice PDF 16 KB Aug 12, 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

Software & Tools

Title Type Format File Size Datesort icon
IDT70T651 BSDL Model Model - BSDL ZIP 9 KB Feb 24, 2004
70T651Verilog Model Model - Verilog TXT 67 KB May 20, 2004
IDT70T651 IBIS Model Model - IBIS ZIP 54 KB Feb 24, 2004