Renesas 70V27S55PFI8

Overview

70V27S55PFI8 from Integrated Device Technology (IDT) is a high-speed, 3.3V, 32K × 16 dual-port static RAM with true simultaneous access to the same memory location from independent left and right ports. It delivers 55 ns maximum read cycle time, supports industrial temperature range (–40°C to +85°C), consumes 500 mW typical active power, and features on-chip semaphore logic and BUSY/INT flags - enabling real-time inter-processor communication in embedded control systems.

For engineers reviewing the 70V27S55PFI8 datasheet, 70V27S55PFI8 pinout, 70V27S55PFI8 application, or 70V27S55PFI8 equivalent, this page provides verified technical context, exact pin-level design meaning, confirmed industrial-grade timing behavior, and validated alternatives for master/slave memory expansion in 32-bit bus architectures.

Technical Context

The 70V27S55PFI8 implements fully asynchronous dual-port architecture with separate address, data, and control buses per port (A0L–A14L/I/O0L–I/O15L vs. A0R–A14R/I/O0R–I/O15R), enabling concurrent read/write operations without arbitration overhead. Its on-chip port arbitration logic resolves contention via BUSY flag assertion (M/S = VIH) or BUSY input gating (M/S = VIL), with tBDD ≤ 50 ns for 55 ns speed grade.

It integrates full hardware semaphore support across eight flags addressed by A0–A2, with tSAA ≤ 65 ns and tSWRD = 5 ns, and supports depth expansion via dual chip enables (CE0/CE1) and width expansion using Master/Slave cascading with M/S pin configuration - all operating from a single 3.3V ±0.3V supply.

Key Specifications

Pinout & Package

70V27S55PFI8 is housed in a 100-pin Thin Quad Flatpack (TQFP) with 0.5 mm pitch, body size 14 mm × 14 mm × 1.4 mm. All VDD pins require local 3.3 V decoupling; all VSS pins must be connected to ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-port SRAM applications.

Compared with CY7C028V-55AXC and AS7C33256PFS-55BIN, the 70V27S55PFI8 uniquely combines 3.3 V operation, on-chip semaphore, BUSY arbitration, and M/S expandability - making it the only drop-in solution for industrial multi-CPU systems requiring deterministic, low-latency inter-processor communication.

Availability

70V27S55PFI8 is available at Aetrix Electronics and suitable for industrial PLCs, avionics data concentrators, medical imaging processors, and automotive ADAS domain controllers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 70V27S55PFI8 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), now part of Renesas Electronics, is a fabless semiconductor company specializing in timing, memory interface, RF, and sensor signal conditioning ICs for communications, computing, and industrial markets.

The IDT70V27 family was designed specifically for high-reliability, real-time inter-processor communication in industrial automation, aerospace, and medical equipment - emphasizing deterministic arbitration, low-power standby, and seamless 32-bit bus expansion.

FAQ

What is the maximum operating temperature range certified for the 70V27S55PFI8?

70V27S55PFI8 is rated for industrial temperature operation from –40°C to +85°C, with all AC and DC specifications guaranteed across this range. The 55 ns access time, BUSY arbitration timing (tBDD ≤ 50 ns), and standby current (ISB3 ≤ 3 mA) are fully characterized and production-tested at both extremes - making it suitable for under-hood automotive modules and factory-floor PLCs.

Does the 70V27S55PFI8 support true simultaneous read/write to the same memory address?

Yes, the 70V27S55PFI8 implements true dual-ported memory cells that allow independent, asynchronous read and write operations to the identical address location from left and right ports. When contention occurs, on-chip arbitration asserts BUSY on the later-arriving port, preserving data integrity without external logic - a core feature confirmed in the functional block diagram and Truth Table V.

How does the M/S pin affect BUSY pin functionality on the 70V27S55PFI8?

When M/S = VIH, 70V27S55PFI8 operates as a Master: BUSYL and BUSYR become push-pull outputs that assert LOW during port contention. When M/S = VIL, it operates as a Slave: BUSYL and BUSYR become inputs that gate writes on the respective port - enabling hierarchical arbitration in multi-device systems. This dual-mode behavior is explicitly defined in Notes 1 and 2 of the Pin Configurations diagram.

Can the 70V27S55PFI8 be used for 32-bit data bus expansion, and how is it implemented?

Yes, 70V27S55PFI8 supports 32-bit expansion via Master/Slave cascading. One device is configured as Master (M/S = VIH), another as Slave (M/S = VIL); the Master's BUSY output connects to the Slave's BUSY input. This configuration uses the built-in BUSY arbitration and CE0/CE1 enables - eliminating external logic and maintaining full 55 ns timing across the expanded bus, as detailed in the Description section and Functional Block Diagram.

What are the key electrical differences between the 'S' and 'L' variants in the IDT70V27 family, and which applies to 70V27S55PFI8?

The 'S' suffix in 70V27S55PFI8 denotes the standard-power variant: active current IDD = 125–135 mA (typ.), standby ISB1 = 15–22 mA (typ.). The 'L' variant offers lower standby (ISB1 ≈ 0.2 mA) but shares identical 55 ns timing, 3.3 V supply, and pinout. 70V27S55PFI8 is the 'S' version - optimized for balanced performance and power in industrial systems where moderate standby savings outweigh ultra-low-power requirements.