Renesas IDT71256SA12PZI8

Overview

IDT71256SA12PZI8 from Renesas Electronics is a 32K × 8-bit (262,144-bit) high-speed CMOS static RAM with 12 ns access time, industrial temperature range (–40°C to +85°C), TSOP-28 package, TTL-compatible I/O, and single 5 V supply operation. It serves as main or buffer memory in real-time control systems requiring deterministic, clockless read/write cycles.

For engineers reviewing the IDT71256SA12PZI8 datasheet, IDT71256SA12PZI8 pinout, IDT71256SA12PZI8 application, or IDT71256SA12PZI8 equivalent, this device delivers verified 12 ns address access (tAA), 6 ns output enable delay (tOE), low-power standby modes (ISB1 = 15 mA), and full static asynchronous operation - critical for legacy industrial controllers, avionics data recorders, and FPGA co-processor buffers where refresh-free reliability is mandatory.

Technical Context

The IDT71256SA12PZI8 implements fully static asynchronous circuitry with no clocks or refresh required. Its architecture includes independent chip select (CS) and output enable (OE) controls, enabling fast read cycles with tCLZ = 4 ns and tOHZ = 6 ns, and write cycles governed by WE-controlled or CS-controlled timing windows.

All 8 bidirectional I/O lines are TTL-compatible with VOH ≥ 2.4 V at IOH = –4 mA and VOL ≤ 0.4 V at IOL = 8 mA. The device supports two standby power states: ISB = 40 mA (TTL-level CS deassertion) and ISB1 = 15 mA (CMOS-level CS deassertion), both specified across the full industrial temperature range.

Key Specifications

Pinout & Package

Package: 28-pin TSOP Type I (PZG28), 8.1 mm × 13.4 mm body, 0.5 mm lead pitch, JEDEC MO-153 compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY62128EV30LL-12ZSXI and AS6C4008-12ZIN, the IDT71256SA12PZI8 offers the lowest industrial-grade standby current (15 mA ISB1), native TSOP-28 compatibility, and documented Renesas lifecycle support for 15+ year industrial deployments - making it optimal for medical, aerospace, and factory automation where obsolescence risk must be minimized.

Availability

IDT71256SA12PZI8 is available at Aetrix Electronics and suitable for industrial PLCs, avionics data loggers, FPGA-based test equipment, and medical imaging subsystems requiring stable component supply across extended product lifecycles.

Supply support for IDT71256SA12PZI8 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

Renesas Electronics Corporation is a global semiconductor leader delivering trusted microcontrollers, analog, power, and memory solutions for industrial, automotive, and infrastructure markets.

The IDT71256SA series originates from Integrated Device Technology (IDT), acquired by Renesas in 2019, and targets high-reliability, refresh-free memory applications in legacy and long-lifecycle embedded systems.

FAQ

What is the maximum operating frequency supported by IDT71256SA12PZI8?

IDT71256SA12PZI8 is an asynchronous SRAM with no clock input, so it does not have an operating frequency specification. Instead, its performance is defined by timing parameters: tRC = 12 ns read cycle time and tWC = 12 ns write cycle time. These values set the upper bound for sustained bus transaction rates - approximately 83 MHz for consecutive reads/writes - assuming compatible controller timing margins and PCB layout.

Does IDT71256SA12PZI8 require refresh circuitry or external clocks?

No, IDT71256SA12PZI8 uses fully static CMOS design and requires no refresh cycles or external clocks. All operations are controlled solely by address, CS, OE, and WE signals. This eliminates timing-critical refresh interrupts and makes the IDT71256SA12PZI8 ideal for safety-critical systems where deterministic behavior is mandatory, such as railway signaling or surgical robotics controllers.

What is the difference between ISB and ISB1 current specifications for IDT71256SA12PZI8?

ISB (40 mA max) applies when CS is driven above VIH (≥2.2 V), representing TTL-level deactivation. ISB1 (15 mA max) applies when CS is driven above VHC (VCC – 0.2 V), representing CMOS-level deactivation. Using ISB1 reduces standby power by 62.5%, which is critical for battery-backed applications like flight data recorders where IDT71256SA12PZI8 operates continuously for weeks without AC power.

Is IDT71256SA12PZI8 pin-compatible with other speed grades in the same family?

Yes, all IDT71256SA variants (12/15/20/25 ns) share identical pinout, package (PZG28), and signal definitions. The IDT71256SA12PZI8 can be substituted for slower versions (e.g., IDT71256SA15PZGI8) without PCB changes, provided timing margins in the host system accommodate the faster access. However, the reverse substitution is not timing-safe.

What does the 'I' suffix in IDT71256SA12PZI8 indicate?

The 'I' in IDT71256SA12PZI8 denotes Industrial temperature grade (–40°C to +85°C), confirmed in the Ordering Information table. The '8' suffix indicates tape-and-reel packaging (8 mm carrier tape, 1000 units/reel). This distinguishes it from tube-packaged variants like IDT71256SA12PZI, and confirms full industrial qualification for use in demanding environments where the IDT71256SA12PZI8 is deployed.