Renesas 7142LA25JI8

Overview

7142LA25JI8 from IDT is a 2K × 8 dual-port static RAM configured as a slave device in master/slave memory expansion systems, supporting independent asynchronous read/write access on left and right ports, 25 ns maximum read cycle time (tRC), 1 μA full-standby current (ISB3), battery-backed data retention at 2 V, and industrial temperature operation (–40°C to +85°C) in a 48-pin flatpack package.

For engineers reviewing the 7142LA25JI8 datasheet, 7142LA25JI8 pinout, 7142LA25JI8 application, or 7142LA25JI8 equivalent, this page delivers verified electrical timing, BUSY input behavior, port arbitration constraints, low-power retention specs, and exact package mapping - all confirmed for the 7142LA25JI8 variant with J-grade industrial screening and flatpack packaging.

Technical Context

The 7142LA25JI8 implements a true dual-port SRAM architecture with fully independent left/right address, control, and I/O buses, enabling concurrent access without internal arbitration logic - unlike the master IDT7132, which contains on-chip arbitration. Its BUSY pin functions strictly as an input to inhibit writes during contention, requiring external coordination via the master's BUSY output.

It supports TTL-compatible 5 V ±10% operation, features automatic power-down per port via CE control, and delivers 2 V data retention capability unique to LA versions. The 25 ns speed grade is validated for industrial temperature range and specified only for flatpack (FP48), LCC (LC48), and DIP (PDG48/SB48) packages - not PLCC.

Key Specifications

Pinout & Package

7142LA25JI8 is packaged in a 48-pin flatpack (FP48) with 0.75″ × 0.75″ × 0.11″ body dimensions. All VCC pins must be connected to 5 V supply; all GND pins to ground. Pin 1 is index-marked; pin numbering follows standard counter-clockwise layout from top view.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C133-25JC and IDT7132LA25JI8, the 7142LA25JI8 uniquely combines industrial temperature rating, 2 V data retention, and slave-only BUSY input behavior - making it irreplaceable in battery-backed, safety-critical dual-processor systems where write arbitration must be externally managed.

Availability

7142LA25JI8 is available at Aetrix Electronics and suitable for industrial motor control, programmable logic controllers, and real-time data acquisition systems requiring stable component supply, long-term lifecycle support, and guaranteed J-grade screening.

Supply support for 7142LA25JI8 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 memory, timing, and interface solutions for industrial, communications, and computing markets.

The IDT7132/7142 product line was designed specifically for deterministic dual-processor memory sharing in real-time control systems, emphasizing hardware-enforced arbitration, low-latency access, and robust operation across extended temperature ranges.

FAQ

What is the function of BUSYL and BUSYR on the 7142LA25JI8?

On the 7142LA25JI8, BUSYL and BUSYR are dedicated input pins that accept active-low BUSY signals from a master IDT7132 device. When asserted, they internally inhibit write operations on the corresponding port to prevent memory contention. Unlike the master, the 7142LA25JI8 contains no arbitration logic - its BUSY pins serve solely as external write-gate controls. This behavior is fixed and cannot be reconfigured.

Does the 7142LA25JI8 support 2 V data retention, and under what conditions?

Yes, the 7142LA25JI8 supports guaranteed data retention at 2.0 V VCC, as specified in Table 6. This applies only when both chip enables (CEL and CER) are held high (VIH), all inputs are at valid CMOS levels (≥ VCC − 0.2 V or ≤ 0.2 V), and ambient temperature is +25°C. At –40°C or +85°C, retention is not characterized, and leakage may exceed specification limits below 2.0 V.

Can the 7142LA25JI8 be used as a standalone dual-port RAM without a master device?

Yes, the 7142LA25JI8 can operate as a standalone dual-port RAM, but only if BUSYL and BUSYR are tied to VCC (inactive high) and external arbitration logic handles potential address-contention scenarios. It lacks on-chip arbitration, so simultaneous writes to identical addresses will result in undefined data - unlike the IDT7132 master, which resolves contention automatically via BUSY output.

What package type does the 7142LA25JI8 use, and are there footprint alternatives?

The 7142LA25JI8 uses a 48-pin flatpack (FP48) package with 0.75″ × 0.75″ body and 0.11″ height. While the same die is offered in LC48 (LCC), PDG48 (plastic DIP), and SB48 (sidebraze DIP), the "J" suffix in 7142LA25JI8 explicitly denotes the flatpack variant with J-grade industrial screening. No PLCC (52-pin) version exists for the 25 ns LA speed grade.

How does the 7142LA25JI8 differ from the SA version in power consumption?

The 7142LA25JI8 draws 1 μA in full standby (ISB3) versus 15 μA for the SA variant - a 15× reduction enabled by optimized CMOS design. Active current is identical (110 mA typ), but LA's lower standby current enables viable battery backup operation for months. This difference is inherent to the LA process and cannot be achieved via external circuitry or bias adjustment.