Renesas 7027S55PF

Overview

7027S55PF from IDT (now Renesas) is a high-speed 32K × 16 dual-port static RAM with true simultaneous access to the same memory location from independent left and right ports, 55 ns maximum access time, TTL-compatible 5V ±10% supply, and industrial temperature range (–40°C to +85°C). It enables real-time inter-processor communication in embedded control systems requiring deterministic arbitration.

For engineers reviewing the 7027S55PF datasheet, 7027S55PF pinout, 7027S55PF application, or 7027S55PF equivalent, key selection criteria include BUSY/INT flag timing (tBDD ≤ 55 ns), on-chip semaphore support for resource locking, master/slave cascading capability, and dual chip-enable architecture for depth expansion without external logic.

Technical Context

The 7027S55PF implements fully asynchronous dual-port operation with separate address, data, and control buses per port, enabling concurrent read/write cycles without external synchronization. Its on-chip arbitration logic resolves contention via address-match or chip-enable priority, with BUSY assertion latency bounded by tBAA ≤ 45 ns (M/S = VIH).

It integrates full hardware semaphore signaling across eight flags addressed by A0–A2, supporting mutual exclusion in multi-CPU systems. The device supports both RAM array access (CE = VIL, SEM = VIH) and semaphore register access (CE = VIH, SEM = VIL) with distinct timing paths validated per AC table 13 and 14.

Key Specifications

Pinout & Package

7027S55PF is packaged in a 100-pin Thin Quad Flatpack (TQFP) with 0.5 mm pitch, body size 14 mm × 14 mm × 1.4 mm. All VCC and GND pins must be connected per datasheet note; package includes dedicated power/ground pairs for noise isolation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-55AXC and IDT70V27L15PF, the 7027S55PF uniquely combines industrial temperature operation, 5V compatibility, and hardware-supported master/slave expansion - making it the only option for retrofitting legacy 5V industrial controllers with deterministic dual-port memory.

Availability

7027S55PF is available at Aetrix Electronics and suitable for industrial PLC communication, avionics data exchange, and medical imaging buffer applications requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature performance.

Supply support for 7027S55PF 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

IDT (Integrated Device Technology), now part of Renesas Electronics, is a fabless semiconductor company specializing in high-performance memory, timing, and interface solutions for communications and industrial markets.

The IDT7027 family was designed specifically for real-time inter-processor communication in deterministic embedded systems, emphasizing hardware arbitration, semaphore support, and seamless 5V integration without external logic.

FAQ

What is the maximum operating temperature range for the 7027S55PF?

The 7027S55PF is rated for industrial temperature operation from –40°C to +85°C, verified per datasheet section 2 and DC electrical characteristics table 6. This specification ensures reliable functionality in factory automation, transportation, and outdoor equipment where ambient thermal stress exceeds commercial-grade limits. The 7027S55PF maintains full 55 ns access timing across this entire range.

Does the 7027S55PF support true simultaneous read/write to the same memory address?

Yes, the 7027S55PF implements true dual-ported memory cells that allow simultaneous access to identical addresses from left and right ports. As confirmed in the Functional Block Diagram and Features section, this architecture enables concurrent operations without internal arbitration delay - essential for lock-free inter-processor communication in real-time systems using the 7027S55PF.

How does the BUSY arbitration mechanism work on the 7027S55PF?

The 7027S55PF provides two BUSY arbitration methods: address-match (tBAA ≤ 45 ns) and chip-enable timing (tBAC ≤ 40 ns), both configurable via the M/S pin. When M/S = VIH (master), BUSYL/BUSYR are outputs asserting during contention; when M/S = VIL (slave), they become inputs that inhibit writes. This hardware logic eliminates software polling, ensuring deterministic conflict resolution in the 7027S55PF.

Can the 7027S55PF be used in a 32-bit data path configuration?

Yes, the 7027S55PF supports 32-bit expansion via its Master/Slave select (M/S) feature. Cascading two devices - one configured as master (M/S = VIH), the other as slave (M/S = VIL) - enables full 32-bit word access without external logic, as documented in the Functional Description and Pin Configurations sections. This capability is intrinsic to the 7027S55PF design and requires no additional discrete components.

What are the valid supply voltage tolerances for the 7027S55PF?

The 7027S55PF operates with a nominal 5.0 V supply, specified over a range of 4.5 V to 5.5 V (±10%) per DC Electrical Characteristics table 7. This tolerance ensures compatibility with standard 5V TTL power domains and accommodates line regulation drift in industrial power supplies, maintaining full timing compliance and functional integrity throughout the 7027S55PF's operational envelope.