Renesas 7025L55GB

Overview

7025L55GB from IDT is a high-speed 8K × 16 (128 Kbit) true dual-port static RAM with independent asynchronous left/right ports, 55 ns maximum read cycle time, 1 µA typical standby current, and TTL-compatible 5 V ±10% operation - used in real-time interprocessor communication, video frame buffers, and military-grade avionics data exchange systems.

For engineers reviewing the 7025L55GB datasheet, 7025L55GB pinout, 7025L55GB application, or 7025L55GB equivalent, key selection criteria include simultaneous dual-port access latency, BUSY/INT arbitration timing, semaphore flag support, battery-backed 2 V data retention, and compatibility with MASTER/SLAVE cascading for 32-bit+ bus expansion.

Technical Context

The 7025L55GB implements full hardware port arbitration with dedicated BUSY flag logic and on-chip semaphore signaling across eight flags addressed via A0–A2. Its dual-port architecture permits concurrent reads to the same memory location without contention.

It supports two distinct operational modes: MASTER (BUSY output) and SLAVE (BUSY input), enabling deterministic priority resolution during address-matched write collisions. The device uses CMOS process technology and features separate upper-byte (UB) and lower-byte (LB) controls for multiplexed bus interfacing.

Key Specifications

Pinout & Package

7025L55GB is housed in a 100-pin TQFP (PNG100) package with 0.5 mm lead pitch, 14 mm × 14 mm body size, and 1.4 mm height. Pin functions are symmetrically distributed for left (L) and right (R) ports, including dual I/O banks (I/O0L–I/O15L / I/O0R–I/O15R), independent chip enables (CEL/CER), byte enables (UBL/UBR, LBL/LBR), and arbitration signals (BUSYL/BUSYR, INTL/INTR, SEML/SEMR).

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C136-55JC and AS7C3256A-55PC, the 7025L55GB uniquely combines 5 V TTL compatibility, 2 V data retention, integrated semaphore logic, and sub-1 µA standby - making it irreplaceable in ruggedized, battery-backed, or arbitration-intensive dual-processor architectures.

Availability

7025L55GB is available at Aetrix Electronics and suitable for real-time interprocessor communication, military avionics data exchange, and industrial PLC memory expansion requiring stable component supply across extended product lifecycles.

Supply support for 7025L55GB 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, acquired by Renesas Electronics in 2019.

The 7025L55GB belongs to IDT's high-reliability dual-port SRAM product line, engineered for deterministic real-time data sharing between heterogeneous processors in aerospace, defense, and industrial control systems.

FAQ

What is the maximum operating temperature range for the 7025L55GB?

The 7025L55GB is rated for industrial temperature operation from –40°C to +85°C. This specification is validated per the datasheet's "Recommended DC Operating Conditions" table and applies to all speed grades within the 7025L family, including the 55 ns variant. It does not support extended military ranges (–55°C to +125°C) unless explicitly ordered as a MIL-qualified part.

Does the 7025L55GB support battery backup operation, and what voltage is required?

Yes, the 7025L55GB supports battery backup with guaranteed data retention at VCC = 2.0 V minimum, as specified in Table 10 ("Data Retention Characteristics"). This feature is exclusive to the 'L' (low-power) version and enables nonvolatile operation during main power interruption - critical for avionics and industrial safety systems.

How does the BUSY signal function in MASTER versus SLAVE configuration on the 7025L55GB?

In MASTER mode (M/S = H), BUSY is an output that asserts when address contention occurs; in SLAVE mode (M/S = L), BUSY is an input that must be deasserted before a write can proceed. This dual-role design enables hierarchical arbitration in cascaded systems - the 7025L55GB uses this mechanism to prevent simultaneous writes to the same location without external logic.

Can the 7025L55GB be used in a 32-bit data bus configuration, and how is that achieved?

Yes, the 7025L55GB supports 32-bit expansion via MASTER/SLAVE cascading. Two devices are connected with M/S pins set oppositely; the MASTER's BUSY output drives the SLAVE's BUSY input, and CE/UB/LB signals are ganged. This configuration maintains full-speed operation without added delay or discrete logic - a capability confirmed in the device description and functional block diagram.

What is the purpose of the SEM (semaphore) pins on the 7025L55GB, and how many flags are available?

The SEML and SEMR pins enable access to eight hardware semaphore flags, addressed via A0–A2. These flags provide atomic set/clear/read operations for inter-processor synchronization - eliminating race conditions in shared-resource access. Each flag is independently controllable through the I/O bus, and their behavior is fully documented in Truth Table II and the "Semaphore Read/Write Control" section of the datasheet.