Renesas 7025L55J

Overview

IDT7025L55J from Integrated Device Technology (IDT) is a high-speed, 8K × 16-bit true dual-port static RAM with independent asynchronous left/right ports, 55 ns maximum read cycle time, 1 mA typical standby current, and TTL-compatible 5V ±10% operation - deployed in real-time digital signal processing systems requiring concurrent access to shared memory buffers.

For engineers reviewing the IDT7025L55J datasheet, IDT7025L55J pinout, IDT7025L55J application, or IDT7025L55J equivalent, key selection considerations include bus arbitration timing (tBDD ≤ 30 ns), semaphore flag support (8 flags, A0–A2 addressed), battery backup data retention at 2V, and compatibility with MASTER/SLAVE cascading for 32-bit+ word systems.

Technical Context

The IDT7025L55J implements full hardware port arbitration with BUSY flag generation on address or chip-enable contention, supporting both address-match and CE-controlled arbitration modes (tAPS = 5 ns setup). Its dual-port architecture permits simultaneous reads from the same location without conflict.

It integrates on-chip semaphore logic (SEML/SEMR) enabling eight software-managed mutual-exclusion flags accessed via I/O0–I/O15, and supports separate upper-byte (UBL/UBR) and lower-byte (LBL/LBR) control for multiplexed bus interfacing - critical for legacy 16-bit data path expansion.

Key Specifications

Pinout & 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 IDT70261L55J, the IDT7025L55J uniquely delivers integrated semaphore and BUSY arbitration in an 84-pin PLCC - reducing system-level logic count and guaranteeing deterministic contention resolution without firmware overhead.

Availability

IDT7025L55J is available at Aetrix Electronics and suitable for digital signal processing systems, industrial motion controllers, and avionics data acquisition requiring stable component supply across extended product lifecycles.

Supply support for IDT7025L55J 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

Integrated Device Technology (IDT) is a fabless semiconductor company specializing in timing, memory interface, RF, and sensor solutions - acquired by Renesas Electronics in 2019.

The IDT7025L55J belongs to IDT's high-speed dual-port SRAM product line, engineered for deterministic real-time systems where concurrent memory access, hardware arbitration, and low-power retention are mission-critical.

FAQ

What is the guaranteed maximum access time for IDT7025L55J under industrial temperature conditions?

The IDT7025L55J is specified with a maximum read cycle time (tRC) of 55 ns across the full industrial temperature range (–40°C to +85°C) and 5.0 V ±10% supply. This value is production-tested and guaranteed - unlike faster variants (e.g., IDT7025L25J), the '55' suffix explicitly denotes this 55 ns rating for industrial-grade operation.

Does IDT7025L55J support battery backup operation, and what voltage is required for data retention?

Yes, the IDT7025L55J supports battery backup operation with guaranteed data retention down to 2.0 V (VDR = 2.0 V). At this voltage, it draws ≤4000 µA in military/industrial grades, enabling reliable state preservation during main power loss - a key feature distinguishing the 'L' (low-power) variant from the 'S' series.

How does the BUSY arbitration mechanism work in IDT7025L55J when configured as MASTER versus SLAVE?

When M/S = H (MASTER), BUSYR outputs a blocking signal to prevent conflicting writes on the right port during address or CE contention. When M/S = L (SLAVE), BUSYL becomes an input that must be asserted externally (e.g., by another MASTER) to gate writes - enabling hierarchical arbitration in multi-device systems without external logic.

Can IDT7025L55J be used to build a 32-bit wide memory system, and what is required to do so?

Yes - the IDT7025L55J supports MASTER/SLAVE cascading via the M/S pin. Two devices can be configured as MASTER and SLAVE to form a 32-bit word: the MASTER handles arbitration and generates BUSY, while the SLAVE responds to BUSY input. No external logic is needed beyond proper CE and byte-enable routing per side.

What is the function of the SEM pin, and how are the eight semaphore flags accessed in IDT7025L55J?

The SEML/SEMR pins enable semaphore register access instead of memory array. When SEM = L and CE or UB/LB = H, the eight flags are addressed using A0–A2 and read/written via I/O0–I/O15. Each flag is a single bit; writing I/O0 sets the selected flag, reading returns its state - providing hardware-accelerated mutual exclusion for multi-threaded firmware.