The 70121 is a high-speed 2K x 9 Dual-Port Static RAM designed to be used as a stand-alone 9-bit Dual- Port RAM or as a "MASTER" Dual-Port RAM together with the 70125 "SLAVE" Dual-Port in 18-bit-or-more word width systems. Using the IDT MASTER/SLAVE Dual-Port RAM approach in 18-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 CE, permits the on-chip circuitry of each port to enter a very low standby power mode.


  • Fully asynchronous operation from either port
  • MASTER 70121 easily expands data bus width to 18 bits or more using SLAVE 70125 chip
  • On-chip port arbitration logic (70121 only)
  • BUSY output flag on Master
  • BUSY input on Slave
  • INT flag for port-to-port communication
  • Battery backup operation—2V data retention
  • TTL-compatible, signal 5V (±10%) power supply
  • Available in 52-pin PLCC
  • Industrial temperature range (–40C to +85C) is available for selected speeds
  • Green parts available, see ordering information

tuneProduct Options

Part Number Part Status Pkg. Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
Active PLCC 52 C Yes Tube
Active PLCC 52 C Yes Reel


Title language Type Format File Size Date
Datasheets & Errata
star 70121/5 Data Sheet Datasheet PDF 323 KB
User Guides & Manuals
Cypress Discontinued Dual-port and FIFO to IDT Cross Reference Guide Guide PDF 123 KB
Application Notes & White Papers
AN-70, Dual-Port Interrupt Expansion Application Note PDF 129 KB
AN-91, The Most Commonly Asked Questions About Async Dual-Ports Application Note PDF 197 KB
AN-68, Dual-Port SRAM Simplifies PC-to-TMS320 Interface Application Note PDF 198 KB
AN-09, Dual-Port SRAMs Yield Bit-Slice Designs Application Note PDF 156 KB
AN-253, Introduction to Multi-Port Memories Application Note PDF 97 KB
PCN# : TB1703-01 Change of MSL Level on PLCC-52 Product Change Notice PDF 157 KB
PCN#: A-0410-02, Change IDT marking logo with new IDT gridless w Product Change Notice PDF 24 KB
PCN# A-0607-06 MMT Thailand as Alternate Assembly Facility for PLCC, SOIC 150mil/300mil Product Change Notice PDF 223 KB
PCN#: TB-0512-01 Reel Color Changed from Blue to Black Product Change Notice PDF 729 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#: A-0309-04, new mold compound G600 material Product Change Notice PDF 134 KB
PCN # SM0308-02 Fab 2 to Fab 4 Transfer Product Change Notice PDF 124 KB
PCN# G-0203-05 Mold Compound Product Change Notice PDF 40 KB
PCN# G0106-01, Moisture Sensitive Label Change Product Change Notice PDF 274 KB
PCN# G9911-05, To qualify low alpha mold compound. Product Change Notice PDF 44 KB