Renesas 7142LA100C

Overview

7142LA100C from IDT is a 2K × 8 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, 100 ns maximum read cycle time, 5 V ±10% supply, industrial temperature range (–40°C to +85°C), and battery-backed data retention at 2 V. It enables 16-bit-or-wider word-width systems when paired with IDT7132 master RAMs.

For engineers reviewing the 7142LA100C datasheet, 7142LA100C pinout, 7142LA100C application, or 7142LA100C equivalent, key selection considerations include BUSY input behavior (not output), low-power standby current (1 µA full standby), 48-pin flatpack/LCC/DIP package compatibility, and timing-critical port arbitration in shared-address multi-port memory designs.

Technical Context

The 7142LA100C implements a true dual-port SRAM architecture with fully independent left and right address/control/I/O buses, enabling concurrent access without internal arbitration logic - unlike the master IDT7132, it contains no on-chip arbitration circuitry and relies entirely on external BUSY signaling from a master device. Its BUSYL and BUSYR pins are dedicated inputs that gate write operations when asserted low.

It supports two distinct power modes: active operation (typ. 325 mW) and multiple standby states - including full CMOS-level standby (ISB3 = 0.2 µA typ.) enabled by high-level CE asserts, and TTL-level standby (ISB1 = 20 mA max. at 100 ns speed grade). Data retention at 2 V is exclusive to LA variants and verified per MIL-PRF-38535 QML for military-grade reliability.

Key Specifications

Pinout & Package

7142LA100C is available in 48-pin flatpack (FP48), LCC (LC48), and DIP (PDG48/SB48) packages. All variants share identical pin mapping and functional assignment.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C133-100AXC, 7142LA100C provides hardware-enforced write inhibition via BUSY inputs and 2 V data retention - critical for deterministic real-time systems. Compared with IDT7132LA100C, it offers lower standby current and simpler slave-side integration but cannot replace master functionality without board-level changes.

Availability

7142LA100C is available at Aetrix Electronics and suitable for industrial motion controllers, aerospace avionics systems, and medical imaging equipment requiring stable component supply, long-term lifecycle support, and MIL-PRF-38535 qualified reliability.

Supply support for 7142LA100C 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 high-performance memory, timing, and interface solutions for communications, computing, and industrial markets.

The IDT7132/7142 product line was designed specifically for deterministic, low-latency dual-port memory applications in real-time control systems - emphasizing hardware arbitration, power efficiency, and military-grade reliability.

FAQ

What is the function of BUSYL and BUSYR on the 7142LA100C?

BUSYL and BUSYR are dedicated input pins on the 7142LA100C. When asserted low by an external master device (e.g., IDT7132), they internally inhibit write operations on the corresponding port. Unlike the master IDT7132, the 7142LA100C does not generate BUSY signals - it only responds to them. This design enables clean hardware-based contention resolution in width-expanded memory systems.

Does the 7142LA100C support true simultaneous read/write operations on both ports?

Yes, the 7142LA100C supports fully independent asynchronous read and write operations on left and right ports - provided no address collision occurs. When both ports access the same memory location concurrently, external BUSY arbitration (via IDT7132 master) is required to prevent data corruption. The 7142LA100C itself has no internal arbitration logic and relies entirely on BUSY input assertion to gate conflicting writes.

What is the significance of the 'LA' suffix in 7142LA100C?

The 'LA' suffix denotes the low-power, battery-backed variant of the IDT7142. It specifies 1 µA typical standby current (ISB3), 2 V data retention capability, and optimized CMOS process for reduced dynamic and static power consumption. This distinguishes it from the 'SA' version, which has higher standby current (5 µA) and no 2 V retention. The '100' indicates 100 ns maximum read cycle time, and 'C' denotes commercial temperature grade - though this specific part is qualified for industrial range (–40°C to +85°C).

Can the 7142LA100C be used without a master IDT7132 device?

Yes - the 7142LA100C can operate as a standalone dual-port SRAM if BUSYL and BUSYR are held high (e.g., pulled up to VCC via 270 Ω resistors), disabling write-inhibit functionality. In this configuration, it behaves identically to a standard dual-port RAM with independent left/right access. However, hardware arbitration for address collisions must then be implemented externally or managed in software, forfeiting the deterministic timing benefits of the master/slave BUSY protocol.

Which packages are available for the 7142LA100C, and are their pinouts identical?

The 7142LA100C is offered in 48-pin flatpack (FP48), 48-pin LCC (LC48), and 48-pin DIP (PDG48/SB48) packages. All share identical pin numbering, signal assignment, and electrical characteristics - only mechanical form factor and thermal/mounting properties differ. Pin 1 is index corner on FP48/LCC; DIP follows standard dual-in-line orientation. No functional differences exist between packages - design reuse across variants is fully supported.