Renesas 7005L55JI8

Overview

7005L55JI8 from IDT is a high-speed 8K × 8 dual-port static RAM with true independent left/right ports, 55 ns max read cycle time (tRC), 2 V data retention capability, and integrated hardware semaphore/arbitration logic. It operates on a single 5 V ±10% supply and supports master/slave cascading for 16-bit+ bus expansion in real-time inter-processor communication systems.

For engineers reviewing the 7005L55JI8 datasheet, 7005L55JI8 pinout, 7005L55JI8 application, or 7005L55JI8 equivalent, key selection criteria include dual-port contention resolution timing (tBDD ≤ 40 ns), low standby current (ISB3 = 0.2 mA typ), battery-backed data retention, and TQFP-64 packaging compatibility with industrial temperature range (–40°C to +85°C).

Technical Context

The 7005L55JI8 implements fully asynchronous dual-port architecture with separate address, control, and I/O buses per port (A0L–A12L/I/O0L–I/O7L and A0R–A12R/I/O0R–I/O7R), enabling simultaneous read/write access to the same memory location without external logic. Its on-chip arbitration uses BUSY flag signaling and M/S pin configuration to resolve port contention deterministically.

Hardware semaphore support operates via dedicated SEM/SEML/SEMR pins and eight flag registers addressed by A0–A2, with tSOP = 15 ns pulse width and tSWRD = 5 ns write-to-read latency. The device enters full standby (ISB3) when both CE inputs exceed VCC – 0.2 V and all inputs are CMOS-level stable.

Key Specifications

Pinout & Package

7005L55JI8 is housed in a 64-pin thin quad flatpack (TQFP) package with 0.5 mm pitch, 14 mm × 14 mm body size, and 1.4 mm height. All VCC and GND pins must be connected per datasheet note; N/C pins are internally unconnected and must remain floating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-55AXC and IDT70V27L25PF, the 7005L55JI8 uniquely combines industrial temperature rating, 2 V data retention, and hardware-supported master/slave cascading-making it irreplaceable in ruggedized embedded systems requiring deterministic dual-port arbitration and power-fail resilience.

Availability

7005L55JI8 is available at Aetrix Electronics and suitable for real-time inter-processor communication, digital signal processing buffering, industrial PLC memory expansion, and avionics data acquisition interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 7005L55JI8 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 semiconductor company specializing in timing, memory interface, RF, and sensor solutions, now part of Renesas Electronics since 2019.

The IDT7005 family was designed specifically for high-reliability dual-ported memory applications in industrial control, telecommunications infrastructure, and military systems demanding deterministic arbitration and robust data retention.

FAQ

What is the maximum operating temperature range for the 7005L55JI8?

The 7005L55JI8 is rated for industrial temperature operation from –40°C to +85°C. This specification is confirmed in the "Maximum Operating Temperature and Supply Voltage" table (Table 205) and applies to all speed grades including the 55 ns variant. Operation outside this range may result in timing violations or data retention failure.

Does the 7005L55JI8 support battery backup operation, and what voltage is required?

Yes, the 7005L55JI8 supports battery backup operation with guaranteed data retention down to 2.0 V (VDR = 2.0 V min). This is explicitly specified in Table 9 ("Data Retention Characteristics") and is a defining feature of the "L" (low-power) version, distinguishing it from the "S" variant.

How does the M/S pin affect BUSY signal behavior in the 7005L55JI8?

When M/S = HIGH, BUSYL and BUSYR function as push-pull outputs indicating port contention; when M/S = LOW, they become inputs that accept BUSY signals from a master device. This dual-mode operation enables hierarchical arbitration in multi-device systems without external logic, as defined in Note 1 of the Pin Names table.

What is the purpose of the SEM/SEML/SEMR pins on the 7005L55JI8?

The SEM/SEML/SEMR pins enable hardware semaphore register access. When SEM = LOW and CE = HIGH, the device enters semaphore mode-allowing atomic read/write of eight flag bits addressed by A0–A2. This eliminates software-based locking and prevents race conditions in multi-processor systems.

Can the 7005L55JI8 perform simultaneous reads from both ports to the same memory address?

Yes, the 7005L55JI8 features true dual-port memory cells that permit simultaneous reads from both left and right ports to identical addresses without contention, arbitration delay, or data corruption. This capability is explicitly stated in the "Features" section and verified in Truth Table I under "Non-Contention Read/Write Control."