Renesas IDT71256L25YI

Overview

IDT71256L25YI from Integrated Device Technology is a 256K-bit (32K × 8) low-power CMOS static RAM with 25 ns maximum access time, TTL-compatible I/O, and 2 V battery backup data retention. It operates across –40°C to +85°C industrial temperature range, consumes ≤3 mA standby current (ISB1), and supports full standby mode via CMOS-level chip select. Used in legacy industrial controllers requiring non-volatile SRAM hold during power loss.

For engineers reviewing the IDT71256L25YI datasheet, IDT71256L25YI pinout, IDT71256L25YI application, or IDT71256L25YI equivalent, key selection criteria include industrial-temperature operation, 25 ns read cycle time, 2 V data retention capability, low-power standby current under 3 µA, and compatibility with 28-pin SOJ packaging for space-constrained embedded designs.

Technical Context

The IDT71256L25YI implements a fully decoded 15-bit address interface (A0–A14) driving a 32K × 8 memory array using high-reliability CMOS technology. Its control logic supports independent chip select (CS), output enable (OE), and write enable (WE) with three distinct operational states: active read/write, TTL-level standby (ISB), and CMOS-level full standby (ISB1).

Timing behavior is defined by strict AC parameters including tRC = 25 ns (read cycle), tAA = 25 ns (address access), and tCHZ = 11 ns (chip deselect to high-Z). Data retention at 2 V is guaranteed over the full industrial temperature range (–40°C to +85°C), with ICCDR ≤ 120 µA typical at 3.0 V and ≤ 800 µA max at 2.0 V.

Key Specifications

Pinout & Package

Package: 28-pin SOJ (SO28-5), 300 mil width, gull-wing lead form, JEDEC MS-012 compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar static RAM applications.

Compared with IDT71256L25YI, CY62256LL-25ZSXIT offers superior standby efficiency but demands PCB redesign, whereas AS6C4008-25ZIN provides true pin-and-function compatibility with improved ISB1 and VDR specs-making it the most seamless replacement for continuity-driven industrial upgrades.

Availability

IDT71256L25YI is available at Aetrix Electronics and suitable for industrial PLCs, avionics subsystems, and medical imaging equipment requiring stable component supply across extended product lifecycles.

Supply support for IDT71256L25YI includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Integrated Device Technology (IDT) was a U.S.-based semiconductor company specializing in timing, memory, and interface solutions before its acquisition by Renesas Electronics in 2019.

IDT71256L25YI belongs to the IDT71256 family of high-reliability CMOS SRAMs designed specifically for industrial and military applications demanding long-term data retention, wide temperature operation, and low-power standby modes.

FAQ

What is the guaranteed data retention voltage for IDT71256L25YI?

IDT71256L25YI guarantees data retention down to 2.0 V across its full industrial temperature range (–40°C to +85°C), with typical retention current (ICCDR) of 120 µA at 3.0 V and up to 800 µA maximum at 2.0 V. This enables reliable battery backup operation using standard 2-cell alkaline or lithium primary cells without regulation.

Does IDT71256L25YI support true CMOS-level standby mode?

Yes, IDT71256L25YI supports full standby mode (ISB1) when chip select (CS) is driven above VHC (VCC – 0.2 V, ≈4.8 V at 5 V supply), reducing supply current to ≤3 µA typical. This is distinct from TTL-level standby (ISB), which draws ≤3 mA and requires CS > VIH only.

Which package type does IDT71256L25YI use, and is it RoHS-compliant?

IDT71256L25YI uses a 28-pin SOJ (SO28-5) package with 300 mil width and gull-wing leads. As a February 2001 product, it predates RoHS enforcement and contains leaded solder terminations; however, Aetrix Electronics provides full material declarations and can source RoHS-compliant equivalents upon request.

Can IDT71256L25YI be used in place of IDT71256S25YI?

IDT71256L25YI replaces IDT71256S25YI in low-power applications: both share identical speed (25 ns), pinout, and organization, but the 'L' version reduces ISB1 from 20 mA (S-version) to ≤3 µA and adds 2 V data retention. No PCB changes are needed, though system firmware must manage the lower standby current path.

What is the maximum operating frequency supported by IDT71256L25YI?

IDT71256L25YI supports a maximum read cycle frequency of 40 MHz, derived from its 25 ns read cycle time (tRC). This allows direct interfacing with microcontrollers and ASICs running at 40 MHz bus clocks without wait states, provided address and control setup/hold times are met per AC specifications.