Renesas 7140SA35JI8

Overview

IDT7140SA35JI8 from Integrated Device Technology (IDT) is a high-speed 1K × 8 dual-port static RAM configured as a SLAVE device in MASTER/SLAVE memory expansion systems, supporting fully asynchronous left/right port access with 35 ns maximum read cycle time, TTL-compatible 5V ±10% operation, and industrial temperature range (–40°C to +85°C). It enables error-free 16-bit-or-wider memory systems without external arbitration logic.

For engineers reviewing the IDT7140SA35JI8 datasheet, IDT7140SA35JI8 pinout, IDT7140SA35JI8 application, or IDT7140SA35JI8 equivalent, key selection considerations include BUSY input behavior (not output), R/W-controlled write timing, CE/OE dual-enable flexibility, port-to-port contention arbitration, and compatibility with IDT7130SA35JI8 as MASTER in 16-bit bus expansion.

Technical Context

The IDT7140SA35JI8 operates as a SLAVE dual-port SRAM with dedicated BUSY inputs (BUSYL, BUSYR) that inhibit writes when asserted low-unlike the MASTER IDT7130 which drives BUSY outputs. Its arbitration logic responds only to address match detection and requires tAPS ≥5 ns setup for deterministic priority resolution.

It supports independent asynchronous reads/writes on left (L) and right (R) ports, each with separate CE, OE, R/W, address (A0–A9), and I/O (I/O0–I/O7) signals. The device uses CMOS process technology, draws 110 mA typical active current at 35 ns speed, and enters low-power standby (ISB1 = 25 mA typ.) when both CEs are high.

Key Specifications

Pinout & Package

Package: 48-pin ceramic flatpack (FP48), body size ≈ 0.75 in × 0.75 in × 0.11 in, hermetically sealed for industrial reliability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1371DV33-166BAXI and IS61WV10248BLL-10MLI, the IDT7140SA35JI8 uniquely delivers hardware-arbitrated dual-port access at 35 ns with zero external logic-critical for deterministic real-time systems where software arbitration introduces jitter or deadlocks.

Availability

IDT7140SA35JI8 is available at Aetrix Electronics and suitable for real-time digital signal processing, redundant control systems, high-speed test equipment data capture, and communications protocol offload applications requiring stable component supply across extended product lifecycles.

Supply support for IDT7140SA35JI8 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 signal conditioning ICs, acquired by Renesas Electronics in 2019.

The IDT7130/7140 family was designed specifically for deterministic, low-latency shared-memory architectures in military, industrial, and telecom infrastructure-emphasizing hardware arbitration, robust ESD tolerance, and extended temperature operation.

FAQ

What is the role of IDT7140SA35JI8 in a MASTER/SLAVE dual-port SRAM configuration?

IDT7140SA35JI8 functions exclusively as the SLAVE device: it accepts BUSY inputs (BUSYL/BUSYR) from external logic or a paired IDT7130 MASTER to inhibit writes during address contention. Unlike the MASTER, it does not drive BUSY outputs, lacks on-chip arbitration logic for priority resolution, and relies on the MASTER for arbitration signaling. This division of responsibility enables seamless 16-bit bus expansion without discrete logic.

Does IDT7140SA35JI8 support battery backup data retention?

No. IDT7140SA35JI8 is the SA (Standard Active) variant and does not support battery backup. Only LA (Low Power Active) versions-such as IDT7140LA35JI8-specify 2.0 V data retention with ICCDR ≤ 4000 µA (military) or ≤ 1500 µA (commercial). The SA suffix confirms standard power consumption (550 mW typical active) and absence of retention circuitry.

What are the critical timing parameters for port-to-port write/read contention on IDT7140SA35JI8?

For IDT7140SA35JI8 as SLAVE, key contention-related timings include tWB = 0 ns (write-to-BUSY input delay), tWDD ≤ 60 ns (write pulse to data delay), and tDDD ≤ 35 ns (write data valid to read data delay). These define the window during which a reading port sees valid data after a writing port completes a write to the same address-essential for verifying coherency in real-time systems.

Can IDT7140SA35JI8 operate with mixed voltage interfaces (e.g., 3.3V controller + 5V SRAM)?

No. IDT7140SA35JI8 requires a single 5.0 V ±10% supply and is strictly TTL-compatible: VIH = 2.2 V min, VIL = 0.8 V max. Direct connection to 3.3V logic violates input voltage specifications and risks unreliable operation or damage. Level translation (e.g., TXB0108) is mandatory for interfacing with 3.3V controllers.

How does interrupt generation work on IDT7140SA35JI8, and what triggers INTL and INTR?

INTL and INTR are open-drain interrupt flags asserted by writing specific addresses: writing 0x3FE to the opposite port sets the local interrupt (e.g., right-port write to 0x3FE sets INTL), and writing 0x3FF clears it. These are edge-triggered, require external pull-up resistors, and remain active until cleared-enabling hardware-synchronized inter-processor signaling without polling overhead in the IDT7140SA35JI8.