Renesas 7142LA55L48B

Overview

7142LA55L48B from IDT is a low-power, 2K × 8 dual-port static RAM configured as a slave device in master/slave memory expansion systems, featuring 55 ns maximum read/write cycle time, 1 μA full-standby current (ISB3), 2 V data retention capability, and industrial temperature operation (–40°C to +85°C) in a 48-pin flatpack package for real-time embedded control and arbitration-critical applications.

For engineers reviewing the 7142LA55L48B datasheet, 7142LA55L48B pinout, 7142LA55L48B application, or 7142LA55L48B equivalent, key selection considerations include BUSY input timing (tWB = 0 ns), port-to-port write-data delay (tWDD ≤ 60 ns), battery-backed data retention at 2 V, and compatibility with IDT7132 master devices in 16-bit-or-wider memory architectures.

Technical Context

The 7142LA55L48B implements independent left/right asynchronous ports with separate address, control, and I/O buses, enabling concurrent access without external arbitration logic. Its BUSY pin functions strictly as an input-unlike the master IDT7132-allowing it to accept write-inhibit signals during address contention.

It supports CE-controlled and R/W-controlled write cycles with guaranteed tWC = 55 ns, tWP = 30 ns minimum, and tBDD ≤ 50 ns BUSY-disable-to-valid-data timing. The device uses CMOS process technology and features TTL-compatible 5 V ±10% single-supply operation with automatic power-down via chip enable.

Key Specifications

Pinout & Package

7142LA55L48B is housed in a 48-lead flatpack (FP48) package with 0.75″ × 0.75″ footprint and 0.11″ height, designed for hermetic sealing and high-reliability military/industrial use. All VCC and GND pins must be externally connected per datasheet note.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C136-55JC, the 7142LA55L48B delivers superior low-power retention and ruggedized packaging; compared with IDT7132LA55L48B, it provides optimized slave behavior with simpler BUSY integration but requires a companion master for arbitration.

Availability

7142LA55L48B is available at Aetrix Electronics and suitable for real-time motion control, avionics data logging, and industrial PLC I/O mapping requiring stable component supply across extended product lifecycles.

Supply support for 7142LA55L48B 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, now part of Renesas Electronics.

The IDT7132/7142 family was designed specifically for deterministic dual-access memory systems in aerospace, defense, and industrial automation-emphasizing hardware arbitration, low-power retention, and MIL-qualified reliability.

FAQ

What is the role of BUSY pins on the 7142LA55L48B?

The BUSYL and BUSYR pins on the 7142LA55L48B function exclusively as inputs-not outputs-and are used to receive write-inhibit signals from a master device (e.g., IDT7132). When asserted low, they internally block write operations to prevent data corruption during address contention. This eliminates need for external logic in master/slave configurations.

Does the 7142LA55L48B support true 2 V data retention?

Yes-the 7142LA55L48B guarantees data retention down to VCC = 2.0 V (VDR), as specified in Table 6. This allows uninterrupted memory hold during brown-out conditions or battery backup operation without external supervision. Retention current is ≤ 4000 µA (military/industrial) at 2 V.

Can the 7142LA55L48B operate as a standalone dual-port RAM?

No-the 7142LA55L48B is explicitly designed as a slave device and lacks on-chip arbitration logic. It requires pairing with an IDT7132 master to resolve port contention. Attempting standalone use results in undefined behavior during simultaneous accesses to the same address.

What is the significance of the "L48B" suffix in 7142LA55L48B?

The "L48B" denotes the 48-pin flatpack (FP48) package with hermetic construction and military-grade screening (QML-compliant). The "B" indicates revision level per IDT's ordering nomenclature and confirms compliance with MIL-PRF-38535 Class B requirements for high-reliability applications.

How does the 7142LA55L48B achieve 1 μA standby current?

The 7142LA55L48B achieves 1 μA full-standby current (ISB3) by disabling both ports via CMOS-level high on CEL and CER (> VCC − 0.2 V), placing all I/O and core logic into ultra-low-leakage state. This is enabled by its LA-series low-power CMOS process and is validated across the full industrial temperature range.