Renesas 7026S25JI

Overview

7026S25JI from IDT is a high-speed 16K × 16 true dual-port static RAM with independent left/right ports, 25 ns maximum access time (industrial grade), 5 V ±10% single supply, and on-chip semaphore arbitration logic. It enables simultaneous asynchronous read/write to the same memory location and supports MASTER/SLAVE cascading for 32-bit+ bus expansion in real-time embedded control systems.

For engineers reviewing the 7026S25JI datasheet, 7026S25JI pinout, 7026S25JI application, or 7026S25JI equivalent, key selection criteria include BUSY arbitration timing (tBAA ≤ 20 ns), dual-port power-down via CE (ISB3 ≤ 0.2 mA), TTL-compatible I/O, and industrial temperature operation (–40°C to +85°C) in 84-pin PLCC.

Technical Context

The 7026S25JI implements fully asynchronous dual-port architecture with separate address, control, and data buses per port - no shared clock or synchronization required. Its on-chip arbitration logic uses chip enable (CEL/CER) and address match detection to assert BUSYL/BUSYR within 20 ns when both ports access identical addresses.

It integrates eight hardware semaphores addressed by A0–A2, accessed via dedicated SEM/CE polarity inversion (CE = VIH, SEM = VIL), enabling inter-processor coordination without external logic. Byte-select (UBL/LBL, UBR/LBR) and master/slave (M/S) configuration support multiplexed bus compatibility and scalable memory width expansion.

Key Specifications

Pinout & Package

7026S25JI is packaged in an 84-pin Plastic Leaded Chip Carrier (PLCC), body size ≈ 1.15 in × 1.15 in × 0.17 in, with all VCC and GND pins requiring local decoupling per datasheet layout guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1362V-25AXI and IDT70V26S25PF, the 7026S25JI uniquely delivers 5 V operation, industrial temperature range, and 84-pin PLCC compatibility - making it the sole option for legacy 5 V industrial controllers requiring drop-in reliability without PCB revision.

Availability

7026S25JI is available at Aetrix Electronics and suitable for industrial PLCs, avionics sensor fusion units, DSP co-processor interfaces, and multi-channel data acquisition systems requiring stable component supply across extended product lifecycles.

Supply support for 7026S25JI 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, RF, and high-performance silicon solutions, now part of Renesas Electronics.

The IDT7026 family was designed specifically for real-time, multi-processor embedded systems requiring deterministic, contention-free shared memory - targeting industrial automation, defense electronics, and telecommunications infrastructure.

FAQ

What is the operating temperature range for the 7026S25JI?

The 7026S25JI is rated for industrial temperature operation from –40°C to +85°C. This specification is validated per the datasheet's "Maximum Operating Temperature and Supply Voltage" table and confirmed in the "Grade" column for the "Industrial" row. The 7026S25JI part number suffix "I" explicitly denotes industrial temperature qualification, ensuring reliability in harsh environments such as factory floors or vehicle-mounted control units.

Does the 7026S25JI support true simultaneous access to the same memory location?

Yes, the 7026S25JI implements true dual-ported memory cells that allow simultaneous read/write operations to the identical address by left and right ports. This capability is explicitly stated in the "Features" section and enabled by on-chip arbitration logic - when contention occurs, BUSY flags assert within 20 ns to stall the later access, preserving data integrity without external logic.

How does the M/S pin affect BUSY pin functionality on the 7026S25JI?

When M/S = H, the 7026S25JI operates as a MASTER: BUSYL and BUSYR are push-pull outputs signaling address contention. When M/S = L, it operates as a SLAVE: BUSYL and BUSYR become write-inhibit inputs - a LOW level blocks writes to the respective port. This behavior is defined in Note 1 of the Functional Block Diagram and verified in Truth Table I and the "Busy Logic" functional description.

What is the minimum write pulse width required for reliable operation of the 7026S25JI?

The 7026S25JI requires a minimum write pulse width (tWP) of 20 ns for the 25 ns speed grade, as specified in Table 13a under "WRITE CYCLE" parameters. This value is measured from the earlier of CE or R/W going low to the end of the write cycle and must be met under all operating conditions including worst-case voltage and temperature.

Can the 7026S25JI be used in a 32-bit memory system without external logic?

Yes, the 7026S25JI supports native 32-bit expansion via MASTER/SLAVE cascading using the M/S pin. When configured as MASTER (M/S = H) and SLAVE (M/S = L), multiple devices synchronize arbitration and BUSY signaling without discrete logic - enabling full-speed, error-free 32-bit word access as documented in the "Description" section and Figure 1 of the datasheet.