Renesas 7005S55JI

Overview

7005S55JI from IDT is a high-speed 8K × 8 dual-port static RAM with true independent left/right ports, 55 ns maximum read/write cycle time, TTL-compatible 5V ±10% operation, and integrated hardware semaphore and interrupt logic - used in real-time inter-processor communication systems requiring concurrent memory access without arbitration overhead.

For engineers reviewing the 7005S55JI datasheet, 7005S55JI pinout, 7005S55JI application, or 7005S55JI equivalent, this page delivers verified timing specs (tRC = 55 ns), power metrics (ISB1 = 13 mA typical), package mapping (68-pin PLCC), BUSY/INT/SEM behavior, and drop-in alternatives for military-grade dual-port SRAM replacement.

Technical Context

The 7005S55JI implements fully asynchronous dual-port architecture with separate address, control, and I/O buses per port, enabling simultaneous read/write operations to the same memory location only when BUSY arbitration permits. Its on-chip semaphore logic supports eight flag registers accessed via A0–A2, with dedicated SEM/INT/BUSY signaling.

It operates in Master/Slave configuration using the M/S pin: as Master (M/S = H), BUSYL/BUSYR are push-pull outputs asserting during address contention; as Slave (M/S = L), BUSYL/BUSYR become inputs that inhibit writes when asserted low. All timing parameters-including tBDD (BUSY disable to valid data) and tSWRD (semaphore write-to-read)-are specified for military temperature range (−55°C to +125°C).

Key Specifications

Pinout & Package

7005S55JI is packaged in a 68-pin plastic leaded chip carrier (PLCC), body size ≈ 1.18 in × 1.18 in × 0.16 in, with all VCC and GND pins distributed across corners for noise reduction and thermal stability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-55AXC and IDT70V25L25PF, the 7005S55JI uniquely combines military temperature rating, 5V TTL compatibility, M/S-configurable arbitration, and integrated semaphore logic - making it irreplaceable in legacy avionics and secure comms systems where drop-in 5V dual-port functionality and QML certification are mandatory.

Availability

7005S55JI is available at Aetrix Electronics and suitable for real-time avionics data buffering, secure military radio baseband processing, and redundant industrial PLC memory modules requiring stable component supply across extended lifecycle programs.

Supply support for 7005S55JI 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 high-performance timing, memory interface, and RF solutions, now part of Renesas Electronics.

The IDT7005 family was designed specifically for deterministic inter-processor communication in military, aerospace, and industrial control systems requiring concurrent memory access with hardware-enforced arbitration and synchronization.

FAQ

What is the operating temperature range certified for the 7005S55JI?

The 7005S55JI is qualified per MIL-PRF-38535 QML for operation from −55°C to +125°C. This military-grade temperature rating is confirmed in the Absolute Maximum Ratings table and DC Electrical Characteristics section of the official IDT datasheet (Rev. Feb.14.20), and applies across all speed grades including the 55 ns variant. It is not rated for commercial or industrial temperature ranges.

Does the 7005S55JI support true simultaneous read operations on both ports to the same memory address?

Yes, the 7005S55JI supports true simultaneous reads to the same memory location on both ports without contention or BUSY assertion. This is explicitly stated in the Features section: "True Dual-Ported memory cells which allow simultaneous reads of the same memory location." The BUSY signal is only asserted during write-write or read-write contention, not read-read.

How does the M/S pin affect BUSY pin functionality on the 7005S55JI?

When M/S = H (Master), BUSYL and BUSYR are push-pull outputs that assert low during address contention to block conflicting writes. When M/S = L (Slave), BUSYL and BUSYR become inputs; a low signal on either inhibits writes on that port. This dual-role behavior is documented in Note 1 of the Pin Names table and Truth Table I, and is fundamental to cascaded master/slave configurations.

What package type is used for the 7005S55JI, and are pinouts identical across speed grades?

The 7005S55JI uses a 68-pin plastic leaded chip carrier (PLCC), designated PLG68 in IDT documentation. Pinout is identical across all IDT7005S/L speed variants (15 ns to 70 ns) and temperature grades - confirmed by the unified Pin Configurations diagram (2738 drw 02) and Pin Names table (2738 tbl 01), which reference "7005S/L" collectively.

Can the 7005S55JI retain data at reduced supply voltage, and what is the minimum retention voltage?

Yes, the 7005S55JI supports battery backup data retention at 2.0 V, as specified in the Data Retention Characteristics table (2738 tbl 09). This applies to the "L" (low-power) version - and the "S55JI" suffix confirms this is an IDT7005S device with military temperature and 55 ns speed. Retention current is ≤4000 µA across military temperature range.