Renesas 7143SA35J8

Overview

7143SA35J8 from IDT is a high-speed 2K × 16 dual-port static RAM configured as a SLAVE device in MASTER/SLAVE memory expansion systems, supporting fully asynchronous independent read/write access on left and right ports with 35 ns max read cycle time, TTL-compatible 5V ±10% operation, and industrial temperature range (–40°C to +85°C). It enables error-free 32-bit-or-wider word width systems without external logic.

For engineers reviewing the 7143SA35J8 datasheet, 7143SA35J8 pinout, 7143SA35J8 application, or 7143SA35J8 equivalent, key selection considerations include BUSY input behavior (not output), absence of on-chip arbitration logic, byte-level write control per port, 68-pin PLCC package compatibility, and use in real-time dual-CPU or DSP+host memory sharing architectures.

Technical Context

The 7143SA35J8 operates as a SLAVE in MASTER/SLAVE dual-port configurations - its BUSY pin functions exclusively as a write-inhibit input (unlike the MASTER IDT7133's open-drain BUSY output), requiring external pull-up when disabled. It lacks on-chip arbitration logic and relies entirely on the MASTER's BUSY signal for contention resolution.

It supports independent, fully asynchronous access on both ports with separate address (A0L–A10L / A0R–A10R), data (I/O0L–I/O15L / I/O0R–I/O15R), and control lines (CEL/CER, R/WLUB/R/WRUB, R/WLLB/R/WRLB, OEL/OER), enabling concurrent CPU and peripheral access to shared memory without software coordination.

Key Specifications

Pinout & Package

7143SA35J8 is packaged in a 68-pin Plastic Leaded Chip Carrier (PLCC), with lead count, body size (~1.18″ × 1.18″), and thermal/mechanical characteristics matching IDT's standard PLCC-68 footprint (package code PLG68).

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT7143SA25J8, the 7143SA35J8 trades 10 ns slower access for lower power and thermal margin; versus CY7C024AV-35JC, it mandates a MASTER/SLAVE topology but delivers deterministic, low-latency expansion to 32+ bit widths without arbitration overhead.

Availability

7143SA35J8 is available at Aetrix Electronics and suitable for real-time motion control, avionics data concentrators, and redundant communication controllers requiring stable component supply across extended product lifecycles.

Supply support for 7143SA35J8 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 IDT7143 family was designed specifically as SLAVE dual-port SRAMs to complement the IDT7133 MASTER in scalable, high-reliability memory expansion systems - targeting aerospace, industrial automation, and telecom infrastructure.

FAQ

What is the role of BUSY pins on the 7143SA35J8?

The BUSY pins (BUSYL and BUSYR) on the 7143SA35J8 function exclusively as write-inhibit inputs - unlike the MASTER IDT7133, this SLAVE device does not generate BUSY signals. When asserted low by an external MASTER, they block write operations on the corresponding port. Pulling them high disables the write-inhibit function, enabling normal write access. This design eliminates arbitration logic in width-expanded systems.

Does the 7143SA35J8 support battery backup or data retention?

No, the 7143SA35J8 does not support battery backup or low-voltage data retention. It belongs to the SA (Standard Active) power class, which lacks the 2V retention capability found only in LA (Low Active) variants like IDT7143LA35J8. For applications requiring data hold during power loss, the LA version must be selected instead.

Can the 7143SA35J8 operate as a standalone dual-port RAM without a MASTER?

Yes, the 7143SA35J8 can operate as a standalone dual-port RAM - both ports function independently with full read/write capability. However, BUSY arbitration is disabled (since BUSY pins are inputs only), so simultaneous writes to the same address will result in undefined data. Use in standalone mode requires external software or logic to manage contention, whereas MASTER/SLAVE pairing provides hardware-enforced arbitration.

What package type is used for the 7143SA35J8, and are there footprint alternatives?

7143SA35J8 uses a 68-pin Plastic Leaded Chip Carrier (PLCC) package, designated PLG68. IDT also offers the same device in 68-pin ceramic PGA, 68-pin flatpack, and 100-pin TQFP. While pinouts are identical across PLCC, PGA, and flatpack variants, the 100-pin TQFP includes NC pins and differs in mechanical dimensions - direct PCB substitution requires layout verification.

How does the 7143SA35J8 differ from the IDT7133SA35J8 in system implementation?

The 7143SA35J8 is a SLAVE device with BUSY inputs and no internal arbitration logic, while the IDT7133SA35J8 is a MASTER with BUSY outputs and on-chip arbitration. In a width-expanded system, one IDT7133SA35J8 coordinates contention resolution and drives BUSY signals to multiple 7143SA35J8 SLAVE devices. Using 7143SA35J8 alone omits arbitration; using IDT7133SA35J8 alone limits expansion flexibility without SLAVE support.