IDT71256S25TDB

The IDT71256S25TDB is a 256-kilobit (32K × 8) CMOS asynchronous static random-access memory (SRAM) manufactured by Renesas Electronics, continuing the legacy of the IDT71256 family. This device operates from a single 5 V supply and employs fully static circuitry that eliminates the need for external refresh clocks, offering straightforward memory interfacing. The -25 suffix designates a 25 ns access time, delivering a balance of speed and low power dissipation typical of the family’s high-performance CMOS process. Packaged in a hermetic ceramic dual-in-line (CDIP) housing, the IC provides robust environmental protection, making it suitable for applications where moisture, temperature extremes, and mechanical stress must be managed without compromising data integrity.

Such characteristics align the SRAM with use in aerospace avionics computers, defense mission systems, and down-hole industrial instrumentation, where non-volatile-like data retention in the absence of refresh is not required but reliable, low-latency scratchpad or buffer memory under harsh conditions is essential. The part also serves in legacy military communication and radar processing modules that demand long-term lifecycle support. From a procurement perspective, this asychronous SRAM is a mature product originally introduced by Integrated Device Technology (IDT) and now stewarded by Renesas; obsolescence risk should be evaluated for new designs, and availability is typically managed through authorized distribution channels dealing in high-reliability components. Engineers sourcing the CDIP variant should verify traceability, date codes, and any applicable screening or military-grade certifications, as the ceramic package and older part number conventions often correlate with ruggedized or extended-temperature requirements, and counterfeit mitigation remains a priority for hi-rel supply chains.