Renesas 7142SA35C

Overview

7142SA35C from IDT is a high-speed 2K × 8 dual-port static RAM configured as a SLAVE device in MASTER/SLAVE memory expansion systems, supporting 35 ns max read/write cycle time, TTL-compatible 5V ±10% operation, and industrial temperature range (–40°C to +85°C), used in real-time data buffering for dual-processor communication and video frame stores.

For engineers reviewing the 7142SA35C datasheet, 7142SA35C pinout, 7142SA35C application, or 7142SA35C equivalent, key selection considerations include BUSY input functionality, 48-pin flatpack/LCC/DIP package compatibility, 2K × 8 asynchronous dual-port architecture, and timing-critical arbitration in width-expanded memory systems.

Technical Context

The 7142SA35C operates as a SLAVE dual-port SRAM with dedicated BUSY input pins (BUSYL, BUSYR) that internally inhibit write operations when asserted low, enabling hardware-controlled port arbitration without external logic. It features independent left/right ports with separate address, control, and I/O lines, each supporting full asynchronous read/write access.

Its 35 ns access timing applies to both tRC (read cycle) and tWC (write cycle), with tAOE = 20 ns and tWP = 25 ns, and supports CMOS-level standby current (ISB3 = 0.2 µA typ. for LA variant - not applicable here) and TTL-level active power (ICC = 80 mA typ. at fMAX). The device requires no on-chip arbitration logic - that resides only in the MASTER IDT7132.

Key Specifications

Pinout & Package

7142SA35C is available in 48-pin flatpack (FP48), leadless chip carrier (LC48), and dual in-line package (PDG48/SB48), all with identical pin mapping. Pin functions are electrically and physically validated per IDT datasheet revision May.27.21.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C133-35JC and IDT7132SA35C, the 7142SA35C uniquely provides native SLAVE functionality with BUSY-as-input behavior - essential for minimizing gate count and guaranteeing deterministic write inhibition in width-expanded systems without redesign.

Availability

7142SA35C is available at Aetrix Electronics and suitable for real-time dual-processor communication, video frame buffering, and avionics data logging requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for 7142SA35C 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, and RF solutions, acquired by Renesas Electronics in 2019.

The IDT7132/7142 product line was designed for high-reliability, low-latency dual-processor memory sharing in military, aerospace, and industrial control systems where hardware arbitration eliminates software overhead.

FAQ

What is the function of BUSYL and BUSYR on the 7142SA35C?

BUSYL and BUSYR are dedicated input pins on the 7142SA35C. When either is driven low, the corresponding port (left or right) internally inhibits write operations to prevent data corruption during address contention. This SLAVE-specific behavior contrasts with the MASTER IDT7132, where BUSY pins are open-drain outputs. The 7142SA35C relies entirely on external arbitration signals - it contains no on-chip arbitration logic.

Can the 7142SA35C operate as a standalone dual-port RAM without a MASTER device?

Yes, the 7142SA35C can operate standalone with both BUSYL and BUSYR tied high (via pull-up resistors), enabling full read/write access on both ports. However, in this configuration, no hardware arbitration occurs - simultaneous writes to the same address will result in undefined data. For deterministic operation under contention, it must be paired with an IDT7132 MASTER or externally managed BUSY logic.

Which packages are compatible with the 7142SA35C pinout?

The 7142SA35C shares identical pin mapping across 48-pin FP48 (flatpack), LC48 (LCC), and PDG48/SB48 (DIP) packages. The 52-pin PLCC (PLG52) variant has a different pinout and is not pin-compatible - its BUSY, CE, and OE pins are relocated. Always verify mechanical dimensions and thermal profiles: FP48 is 0.75″ × 0.75″ × 0.11″, LC48 is 0.57″ × 0.57″ × 0.68″.

Does the 7142SA35C support battery backup data retention?

No. Battery backup data retention (down to 2V VCC) is exclusive to the LA variant (e.g., 7142LA35C). The 7142SA35C is the standard-power version, with ISB3 = 1.0 µA typical full-standby current at CMOS-level inputs, but no guaranteed data retention below 4.5 V. For battery-backed applications, specify the LA suffix and confirm industrial temperature support.

How does the 7142SA35C differ from the 7132SA35C in system integration?

The 7142SA35C is a SLAVE-only device with BUSY inputs and no internal arbitration logic, while the 7132SA35C is a MASTER with BUSY outputs and on-chip arbitration. In a width-expanded system, one 7132SA35C coordinates multiple 7142SA35Cs - the 7142SA35C cannot substitute for the 7132SA35C, nor can two 7142SA35Cs arbitrate against each other. Their roles are fixed and non-interchangeable.