Renesas 7005L35J

Overview

7005L35J from IDT is a high-speed 8K × 8 dual-port static RAM with true independent left/right ports, 35 ns max read cycle time (tRC), 2V data retention capability, and integrated hardware semaphore/arbitration logic. It operates on single 5V ±10% supply and supports master/slave cascading for 16-bit+ bus expansion in real-time inter-processor communication systems.

For engineers reviewing the 7005L35J datasheet, 7005L35J pinout, 7005L35J application, or 7005L35J equivalent, this device delivers deterministic port-to-port arbitration, battery-backed data retention, and TTL-compatible I/O - critical for embedded control, avionics data buffers, and industrial PLC memory coherency designs.

Technical Context

The 7005L35J implements fully asynchronous dual-port architecture with separate address, control, and bidirectional I/O buses per port (A0L–A12L/I/O0L–I/O7L and A0R–A12R/I/O0R–I/O7R). Its on-chip arbitration logic uses BUSY flag signaling and M/S pin configuration to resolve simultaneous access contention without external logic.

It supports two distinct operational modes: RAM access (CE = VIL, SEM = VIH) and semaphore register access (CE = VIH, SEM = VIL), with dedicated 3-bit address decoding (A0–A2) for eight semaphore flags. All timing parameters-including tBDD (BUSY disable to valid data) and tSWRD (SEM write-to-read)-are specified for 35 ns speed grade across commercial/industrial/military temperature ranges.

Key Specifications

Pinout & Package

7005L35J is packaged in a 64-pin thin quad flatpack (TQFP), measuring 14 mm × 14 mm × 1.4 mm, with 0.5 mm lead pitch and exposed thermal pad. Pin 1 marked via corner notch; pin numbering follows standard counter-clockwise sequence from top-left.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-35AXC and IDT70V25L35PF, the 7005L35J uniquely integrates hardware semaphore and BUSY arbitration in a 5V/8-bit dual-port package, making it optimal for cost-sensitive, legacy 5V real-time control systems where deterministic contention resolution is mandatory.

Availability

7005L35J is available at Aetrix Electronics and suitable for avionics data buffering, industrial PLC memory coherency, and medical imaging frame store applications requiring stable component supply, long-term lifecycle support, and military/industrial temperature compliance.

Supply support for 7005L35J 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 sensor solutions, now part of Renesas Electronics.

The IDT7005 product line was designed specifically for deterministic, low-latency inter-processor communication in real-time embedded systems-emphasizing hardware arbitration, dual-port concurrency, and battery-backed data integrity.

FAQ

What is the maximum operating temperature range certified for the 7005L35J?

The 7005L35J is rated for industrial temperature operation from −40°C to +85°C, with full AC/DC electrical specifications guaranteed across this range. This is explicitly confirmed in Table 5 of the datasheet under "Industrial" grade, and applies to all 35 ns speed variants including 7005L35J.

Does the 7005L35J support true simultaneous read operations from both ports to the same memory location?

Yes, the 7005L35J implements true dual-port memory cells that permit concurrent reads from both left and right ports to identical addresses without conflict, timing penalty, or data corruption - a core feature highlighted in the "Features" section and verified in Truth Table I.

How does the 7005L35J handle memory contention when both ports attempt writes to the same address?

The 7005L35J uses hardware arbitration: when contention occurs, the BUSY flag (BUSYL/BUSYR) asserts to block the later-arriving write, and tAPS (5 ns arbitration priority setup time) ensures deterministic resolution. The winning port completes its write; the blocked port must retry after BUSY deasserts - detailed in Waveform 13 and Table 15.

What is the function of the M/S pin on the 7005L35J, and how does it affect BUSY behavior?

The M/S pin configures the 7005L35J as Master (M/S = H) or Slave (M/S = L). In Master mode, BUSYL and BUSYR are push-pull outputs signaling contention; in Slave mode, they become inputs that inhibit writes when driven low by a Master - enabling hierarchical arbitration in multi-device systems.

Can the 7005L35J retain data when main VCC drops below operational voltage?

Yes - the 7005L35J supports data retention at VCC = 2.0 V minimum, drawing ≤4000 µA (typical 100 µA) in retention mode. This is a defined L-version feature confirmed in Table 9 and the "Data Retention Waveform" diagram, enabling reliable backup using coin-cell batteries.