Renesas 7027S55PFI8

Overview

7027S55PFI8 from IDT (Integrated Device Technology) is a high-speed 32K × 16 dual-port static RAM with true dual-ported memory cells enabling simultaneous read/write access to the same address, 55 ns maximum access time, TTL-compatible 5V ±10% supply, and industrial temperature range (–40°C to +85°C). It serves as a stand-alone or master/slave-configured memory in real-time embedded systems requiring deterministic inter-processor communication.

For engineers reviewing the 7027S55PFI8 datasheet, 7027S55PFI8 pinout, 7027S55PFI8 application, or 7027S55PFI8 equivalent, key selection criteria include port arbitration timing (tBDD ≤ 55 ns), BUSY flag behavior under M/S = VIH configuration, semaphore support for eight flags via A0–A2, dual-byte control (UBL/LBR), and compatibility with 100-pin TQFP layouts in space-constrained industrial controllers.

Technical Context

The 7027S55PFI8 implements fully asynchronous dual-port operation with independent left/right address, control, and I/O buses. Its on-chip arbitration logic resolves contention via address-match or chip-enable-driven BUSY assertion, with tAPS = 5 ns setup for priority resolution.

It supports semaphore signaling using dedicated SEM pins and A0–A2 addressing for eight shared flags, and provides interrupt generation by writing to fixed mailbox addresses (7FFE_H and 7FFF_H). The device uses CMOS technology with active power consumption of 190 mA (typ.) and full standby current of 1.0 mA (typ.) at V_CC = 5.0 V.

Key Specifications

Pinout & Package

7027S55PFI8 is housed in a 100-pin TQFP (Thin Quad Flatpack) package with 0.5 mm pitch, body size 14 mm × 14 mm × 1.4 mm. All V_CC and GND pins must be externally decoupled per layout guidelines.

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 7027S55PFI8 uniquely delivers 5V-native operation, industrial temperature qualification, and hardware semaphore support in a pin-compatible footprint - making it irreplaceable for legacy 5V industrial designs requiring guaranteed BUSY arbitration and mailbox interrupts.

Availability

7027S55PFI8 is available at Aetrix Electronics and suitable for industrial motion control, avionics data concentrators, medical imaging subsystems, telecom line cards, and real-time embedded systems requiring stable component supply across extended product lifecycles.

Supply support for 7027S55PFI8 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) was a fabless semiconductor company specializing in timing, memory, and interface solutions before its acquisition by Renesas Electronics in 2019. It pioneered high-performance dual-port SRAM architectures for real-time systems.

The IDT7027 family was designed specifically for deterministic inter-processor communication in industrial, aerospace, and medical systems where hardware-enforced arbitration, mailbox interrupts, and sub-100 ns latency are mandatory design requirements.

FAQ

What is the operating temperature range for the 7027S55PFI8?

The 7027S55PFI8 is rated for industrial temperature operation from –40°C to +85°C. This specification is confirmed in the "Recommended DC Operating Conditions" table (Table 6) and applies to all speed grades including the 55 ns variant. No derating is required within this range, and the device maintains full timing compliance per AC Electrical Characteristics Table 12.

Does the 7027S55PFI8 support true simultaneous access to the same memory location?

Yes, the 7027S55PFI8 implements true dual-ported memory cells that allow simultaneous read/write access to identical addresses. When contention occurs, on-chip arbitration asserts BUSY on the later-arriving port, with tBDD ≤ 55 ns ensuring deterministic resolution - a feature explicitly stated in the Functional Block Diagram and Truth Table V.

How does the M/S pin affect BUSY pin functionality on the 7027S55PFI8?

When M/S = VIH, the 7027S55PFI8 operates as a Master: BUSYL and BUSYR are push-pull outputs that signal contention to external logic. When M/S = VIL, it operates as a Slave: BUSYL and BUSYR become inputs that internally inhibit writes during contention. This dual-mode behavior is defined in Note 1 of the Pin Configurations section and Figure 11 timing diagrams.

Can the 7027S55PFI8 be used in a 32-bit data bus configuration?

Yes, the 7027S55PFI8 supports 32-bit expansion via Master/Slave cascading. Two devices can be connected using the M/S pin: one configured as Master (M/S = VIH) and the other as Slave (M/S = VIL), enabling full 32-bit word access without external logic. This capability is documented in the "IDT MASTER/SLAVE Dual-Port RAM approach" description on page 2.

What are the valid semaphore address ranges for the 7027S55PFI8?

The 7027S55PFI8 implements eight semaphore flags addressed by A0–A2 (i.e., addresses 000₂ through 111₂). These are accessed only when SEM = VIL and CE = VIH, as specified in Truth Table III and the Functional Description section (page 16). Each flag is written via I/O0 and read across all 16 I/O lines.