Renesas 7026S55J8

Overview

IDT7026S55J8 from IDT (Integrated Device Technology) is a high-speed 16K × 16 true dual-port static RAM with independent left/right ports, 55 ns maximum read cycle time, TTL-compatible 5V ±10% operation, and on-chip semaphore arbitration logic. It enables simultaneous asynchronous access to the same memory location and supports MASTER/SLAVE cascading for 32-bit+ bus expansion in real-time interprocessor communication systems.

For engineers reviewing the IDT7026S55J8 datasheet, IDT7026S55J8 pinout, IDT7026S55J8 application, or IDT7026S55J8 equivalent, key selection considerations include BUSY arbitration timing (tBDD ≤ 40 ns), dual-port power-down via CE control, industrial temperature range (–40°C to +85°C), and 84-pin PLCC package compatibility with legacy military-grade board layouts.

Technical Context

The IDT7026S55J8 implements fully asynchronous dual-port architecture with separate address, control, and I/O buses per port - enabling concurrent read/write operations without internal synchronization overhead. Its on-chip arbitration logic uses chip enable (CEL/CER) and address match detection to assert BUSYL/BUSYR within 45 ns (tBAA) when contention occurs.

It integrates eight hardware semaphores accessible via A0–A2 addressing and I/O0 write/data lines, supporting inter-processor coordination without external logic. The device operates in MASTER mode (M/S = H) for BUSY output flagging or SLAVE mode (M/S = L) for BUSY input write inhibition - both modes support full 16-bit data width per port.

Key Specifications

Pinout & Package

Package: 84-pin Plastic Leaded Chip Carrier (PLCC), body size ≈ 1.15 in × 1.15 in × 0.17 in, lead pitch 0.05 in, RoHS-compliant green variant available.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C136-55JC and R1EX24016DSG-55, the IDT7026S55J8 uniquely integrates both BUSY arbitration and eight hardware semaphores in a single 84-pin PLCC package - reducing component count, PCB area, and timing uncertainty in safety-critical dual-processor systems.

Availability

IDT7026S55J8 is available at Aetrix Electronics and suitable for industrial automation, avionics data exchange, and military radar processing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for IDT7026S55J8 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) is a fabless semiconductor company specializing in timing, memory interface, and RF solutions, now part of Renesas Electronics since 2019.

The IDT7026S55J8 belongs to IDT's high-speed dual-port SRAM product line, designed specifically for deterministic interprocessor communication in real-time embedded systems where hardware-coordinated memory access is mandatory.

FAQ

What is the operating temperature range for the IDT7026S55J8?

The IDT7026S55J8 is rated for industrial temperature operation from –40°C to +85°C. This specification is confirmed in the Absolute Maximum Ratings table and DC Electrical Characteristics section of the official datasheet. The device meets this range under full 5V ±10% supply and all specified timing conditions. No derating is required within this envelope, making IDT7026S55J8 suitable for factory-floor controllers and outdoor communications equipment.

Does the IDT7026S55J8 support true simultaneous read/write to the same memory address?

Yes, the IDT7026S55J8 implements true dual-ported memory cells that allow simultaneous access to the same location - one port may read while the other writes. However, when both ports attempt writes to the same address, the on-chip BUSY arbitration logic asserts BUSYL or BUSYR to stall the later access. This behavior is explicitly documented in the Functional Block Diagram and Truth Table I, confirming deterministic resolution without data corruption.

How does the semaphore function work on the IDT7026S55J8?

The IDT7026S55J8 includes eight dedicated hardware semaphore flags accessed via A0–A2 addressing and controlled using the SEM pin. When SEM = VIL and CE = VIH, writes to I/O0 set or clear a flag; reads return the flag state across all 16 I/O lines. This is verified in Truth Table II and the Functional Description section. The semaphores operate independently of main memory access, enabling lock-free coordination between processors without consuming RAM space.

What package type is used for the IDT7026S55J8?

The IDT7026S55J8 is packaged in an 84-pin Plastic Leaded Chip Carrier (PLCC), as confirmed by the Pin Configurations diagram (DSC 2939/17, page 3) and ordering information footnote stating "PLCC" for J-suffix variants. The package dimensions are approximately 1.15 in × 1.15 in × 0.17 in, with gull-wing leads compatible with standard surface-mount reflow profiles.

Can the IDT7026S55J8 be used in MASTER/SLAVE configurations for wider data buses?

Yes, the IDT7026S55J8 supports MASTER/SLAVE cascading via the M/S pin to expand data width beyond 16 bits. When configured as MASTER (M/S = H), BUSY outputs coordinate arbitration; as SLAVE (M/S = L), BUSY inputs accept write inhibition signals. This capability is detailed in the Features list and Description section, enabling seamless 32-bit-or-more word systems without external logic - a key differentiator versus standard SRAMs.