Renesas 7143LA20J8

Overview

7143LA20J8 from IDT is a high-speed 2K × 16 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 with 20 ns maximum read cycle time, 2V data retention, and 1 mW typical standby power. It enables error-free 32-bit-or-wider memory systems without external logic in industrial embedded controllers.

For engineers reviewing the 7143LA20J8 datasheet, 7143LA20J8 pinout, 7143LA20J8 application, or 7143LA20J8 equivalent, key selection considerations include BUSY input behavior (not output), byte-level write control per port, 68-pin PLCC package compatibility, and LA-series low-power battery backup operation at 2V.

Technical Context

The 7143LA20J8 operates as a SLAVE dual-port SRAM with dedicated BUSY input (not output) for write inhibition during address contention - unlike the MASTER IDT7133 which provides BUSY arbitration logic and open-drain BUSY output. It supports fully asynchronous, independent port access with separate CE, R/W, OE, and address buses for each port.

Its low-power LA variant delivers 1050 mW typical active power and 1 mW typical standby power, enabling battery-backed data retention down to 2V. The device uses TTL-compatible 5V ±10% supply and features separate upper/lower byte write enables (R/WLUB/R/WLLB and R/WRUB/R/WRLB) for granular memory control.

Key Specifications

Pinout & Package

7143LA20J8 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 IDT7143LA25J8, the 7143LA20J8 delivers tighter 20 ns timing for latency-critical inter-processor links; compared with CY7C1371DV33-200BZI, it offers hardware BUSY arbitration and 5V TTL compatibility but lacks DDR throughput - making it optimal for deterministic industrial control over raw speed.

Availability

7143LA20J8 is available at Aetrix Electronics and suitable for real-time inter-processor communication, industrial PLC data exchange, and battery-backed configuration storage requiring stable component supply across extended product lifecycles.

Supply support for 7143LA20J8 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 IDT7143 series was designed specifically as SLAVE dual-port SRAMs to pair with IDT7133 MASTER devices, enabling scalable, contention-free memory expansion in deterministic embedded systems.

FAQ

What is the role of BUSY pins on the 7143LA20J8?

The BUSYL and BUSYR pins on the 7143LA20J8 serve exclusively as inputs - not outputs - and are used to receive BUSY signals from a MASTER IDT7133 device during address contention. When asserted HIGH, they internally gate write operations on the corresponding port to prevent data corruption. Unlike the MASTER, the 7143LA20J8 contains no arbitration logic and requires external BUSY source coordination.

Can the 7143LA20J8 operate as a standalone dual-port RAM without a MASTER device?

Yes, the 7143LA20J8 can operate independently as a dual-port SRAM with full asynchronous read/write capability on both ports. Its BUSY pins default to inactive (HIGH) when unused, allowing normal operation. However, hardware arbitration during simultaneous access to the same address requires external logic or careful software coordination - the built-in BUSY input functionality is only active when driven by an IDT7133 MASTER.

What is the minimum supply voltage for data retention on the 7143LA20J8?

The 7143LA20J8 guarantees data retention down to VCC = 2.0 V, as specified in Table 8 of the datasheet. This applies across the full industrial temperature range (–40°C to +85°C) and is validated for long-term operation in battery-backup configurations. Below 2.0 V, data retention is not assured and memory contents may be lost.

Does the 7143LA20J8 support byte-level write control?

Yes, the 7143LA20J8 provides independent upper and lower byte write enables for both ports: R/WLUB and R/WLLB control writes to I/O8L–I/O15L and I/O0L–I/O7L respectively on the left port; R/WRUB and R/WRLB perform the same function for the right port. This enables true 8-bit partial-word writes without read-modify-write sequences.

Is the 7143LA20J8 pin-compatible with the IDT7133LA20J8?

Yes, the 7143LA20J8 shares identical pinout, package dimensions, and electrical characteristics with the IDT7133LA20J8 - including all address, data, control, and power terminals. This allows direct PCB footprint reuse in MASTER/SLAVE width-expansion designs. The only functional difference is internal: IDT7133 includes BUSY arbitration logic and open-drain BUSY outputs, while IDT7143 implements BUSY as inputs only.