Renesas 7143LA90J

Overview

7143LA90J from IDT is a low-power, 2K × 16-bit (32 Kbit), asynchronous dual-port SRAM designed as a SLAVE device in MASTER/SLAVE memory expansion configurations. It features 90 ns maximum read cycle time, 1 µA typical standby current, battery backup data retention at 2 V, and operates across industrial temperature range (–40°C to +85°C) with single 5 V ±10% supply. It enables error-free 32-bit-or-wider memory systems without external logic.

For engineers reviewing the 7143LA90J datasheet, 7143LA90J pinout, 7143LA90J application, or 7143LA90J equivalent, this page delivers verified timing parameters, BUSY input behavior, byte-select write control, industrial-grade reliability, and direct compatibility with IDT7133 MASTER devices for width-expansion designs.

Technical Context

The 7143LA90J implements fully asynchronous dual-port operation with independent left/right address, control, and I/O buses - enabling concurrent read/write access to any memory location. Its BUSY pin functions exclusively as an input (unlike the MASTER IDT7133), used to gate write operations during contention arbitration.

It supports separate upper- and lower-byte write enables (R/WLUB/R/WLLB and R/WRUB/R/WRLB), TTL-compatible signaling, and automatic power-down via chip enable (CE/CER). The device uses CMOS high-performance technology and includes on-chip circuitry for 2 V data retention during battery backup mode.

Key Specifications

Pinout & Package

7143LA90J is packaged in a 68-pin Plastic Leaded Chip Carrier (PLCC, code PLG68), measuring approximately 0.95 in × 0.95 in × 0.17 in. Both VCC and GND pins must be connected for reliable operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1371DV33-100AXC and IDT7133LA90J, the 7143LA90J uniquely delivers 5 V-compatible, low-power, SLAVE-only dual-port operation with hardware BUSY input - making it irreplaceable in legacy industrial systems requiring seamless integration with IDT7133 MASTER devices.

Availability

7143LA90J is available at Aetrix Electronics and suitable for industrial motion control, redundant communication controllers, digital signal processor interfaces, and test equipment pattern memory requiring stable component supply and long-term obsolescence management.

Supply support for 7143LA90J 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, and RF solutions, now part of Renesas Electronics.

The IDT7133/7143 family was engineered for deterministic, contention-free shared memory in real-time embedded systems - targeting industrial automation, avionics, and telecom infrastructure where dual-processor synchronization and hardware arbitration are critical.

FAQ

What is the role of the BUSY pin on the 7143LA90J?

The BUSY pin on the 7143LA90J functions exclusively as an input - unlike the MASTER IDT7133, which drives BUSY as an open-drain output. When pulled LOW, it inhibits write operations to the corresponding port, enabling hardware-based arbitration in MASTER/SLAVE configurations. This design eliminates external pull-up resistors and simplifies routing in width-expanded memory systems using the 7143LA90J as SLAVE.

Can the 7143LA90J operate as a standalone dual-port RAM without a MASTER device?

Yes, the 7143LA90J can operate as a standalone dual-port SRAM. Its BUSY pins may be tied HIGH to disable write inhibition, allowing unrestricted concurrent access. However, in cases where both ports attempt writes to the same address simultaneously, no internal arbitration occurs - the result is undefined. For deterministic contention resolution, pairing with an IDT7133 MASTER is required. The 7143LA90J retains full functionality (90 ns access, 2 V retention, byte-select writes) in standalone mode.

What is the significance of "LA" in the 7143LA90J part number?

The "LA" suffix in 7143LA90J denotes the Low-Power version of the IDT7143 dual-port SRAM. It specifies 1050 mW typical active power consumption and 1 µA typical standby current - significantly lower than the "SA" (Standard Active) variant's 1150 mW active and 5 µA standby. The LA version also supports 2 V data retention, making it suitable for battery-backed applications where energy efficiency and backup reliability are critical design requirements.

Which packages are available for the 7143LA90J, and is PLCC the only option?

The 7143LA90J is available in multiple packages per the datasheet: 68-pin ceramic PGA (GU68), 68-pin flatpack (FP68), 68-pin PLCC (PLG68), and 100-pin TQFP (PNG100). The "J" suffix in 7143LA90J specifically indicates the PLCC (PLG68) package. Other variants exist (e.g., 7143LA90PG for PGA), but 7143LA90J refers unambiguously to the 68-pin PLCC configuration with industrial temperature grading and 90 ns speed grade.

How does the 7143LA90J handle simultaneous read/write to the same address from both ports?

The 7143LA90J has no internal arbitration logic - it relies on external BUSY signaling from a MASTER device (e.g., IDT7133) to prevent simultaneous writes. If both ports attempt writes to the same address without BUSY coordination, the result is undefined and may cause data corruption. During simultaneous reads, no conflict occurs. The 7143LA90J's BUSY inputs are designed to receive arbitration signals; when asserted, they gate the write path - ensuring only one port writes at a time in properly configured MASTER/SLAVE systems.