Renesas 7140SA55P

Overview

7140SA55P from IDT is a 1K × 8 dual-port static RAM configured as a SLAVE device in MASTER/SLAVE memory expansion systems, supporting independent asynchronous access on left and right ports with 55 ns max read/write cycle time, TTL-compatible 5V ±10% supply, 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 7140SA55P datasheet, 7140SA55P pinout, 7140SA55P application, or 7140SA55P equivalent, this page delivers verified timing parameters, BUSY input behavior, port-to-port arbitration constraints, and package-specific DC/AC electrical characteristics for reliable integration into real-time embedded control and communications subsystems.

Technical Context

The 7140SA55P operates as a SLAVE in a MASTER/SLAVE dual-port SRAM pair with IDT7130, accepting BUSY input signals (BUSYL/BUSYR) to inhibit writes during address contention-unlike the MASTER's open-drain BUSY outputs. Its arbitration logic responds only to address match detection and requires tAPS ≥ 5 ns setup to prevent indeterminate BUSY assertion.

All I/O pins are TTL-compatible with VIL ≤ 0.8 V and VOH ≥ 2.4 V at IOH = –4 mA; dynamic current draw is 155 mA (typ.) under full activity at 55 ns speed grade, while ISB1 standby current is 20 mA (typ.) with both CE inputs high and f = fMAX.

Key Specifications

Pinout & Package

7140SA55P is packaged in a 48-pin plastic DIP (PDG48) with 0.600-inch width, body dimensions ≈ 0.55 in × 0.61 in × 0.19 in, and through-hole mounting. All VCC pins must be decoupled locally; all GND pins require low-impedance ground plane connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1352BV-55AXC and IDT7132SA55P, the 7140SA55P offers optimized cost and footprint for 1K × 8 SLAVE roles in existing 5 V industrial designs, retaining full compatibility with IDT7130 MASTER while avoiding voltage translation or package migration.

Availability

7140SA55P is available at Aetrix Electronics and suitable for motor control systems, telecom line cards, avionics data acquisition, and industrial PLCs requiring stable component supply with long-term industrial temperature support.

Supply support for 7140SA55P 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, RF, and sensor signal processing ICs, now part of Renesas Electronics.

The IDT7130/7140 family was designed specifically for high-reliability dual-ported memory expansion in real-time embedded systems where deterministic latency and hardware arbitration are critical.

FAQ

What is the function of BUSYL and BUSYR on the 7140SA55P?

On the 7140SA55P, BUSYL and BUSYR are dedicated input terminals-not outputs-that accept active-low BUSY signals from a MASTER IDT7130 device. When either signal is pulled low, the corresponding port (left or right) internally inhibits write operations to prevent data corruption during address contention. This SLAVE-only behavior distinguishes 7140SA55P from the MASTER IDT7130, which drives open-drain BUSY outputs requiring external pull-ups.

Can the 7140SA55P operate as a standalone dual-port SRAM without a MASTER device?

Yes, the 7140SA55P can operate as a standalone dual-port SRAM, but only in configurations where external arbitration logic manages BUSY signaling-since it lacks on-chip arbitration output capability. In such cases, BUSYL and BUSYR must be held high (e.g., via pull-up resistors) to enable writes. However, its primary design intent and tested use case is as a SLAVE paired with IDT7130, where hardware arbitration is fully handled without discrete components.

What is the maximum clock frequency supported by the 7140SA55P in a synchronous system?

The 7140SA55P does not have a clock input-it is a fully asynchronous device. Its timing is governed by setup/hold requirements relative to control signals (CE, OE, R/W) and address transitions. With a 55 ns read cycle time (tRC), the maximum sustainable transaction rate is approximately 18.2 MHz assuming zero dead time between cycles. System-level timing must account for propagation delays, especially for BUSY-controlled arbitration windows defined by tBDD (≤35 ns) and tAPS (≥5 ns).

Does the 7140SA55P support battery backup or data retention mode?

No, the 7140SA55P does not support battery backup or low-voltage data retention. That capability is exclusive to LA-suffixed variants (e.g., 7140LA55P), which guarantee data retention down to 2.0 V. The "SA" suffix denotes standard active power profile with typical ICC = 155 mA and ISB1 = 20 mA-optimized for performance rather than ultra-low-power retention.

Which packages are available for the 7140SA55P, and is the PDG48 version lead-free?

The 7140SA55P is available in 48-pin plastic DIP (PDG48), 48-pin sidebraze DIP (SB48), 48-pin LCC (LC48), and 48-pin ceramic flatpack (FP48). Per IDT documentation, green (lead-free) versions are offered-ordering code suffix "P" (as in 7140SA55P) explicitly denotes lead-free PDG48 packaging compliant with RoHS Directive 2011/65/EU, with matte tin lead finish and JEDEC-standard reflow profiles.