Renesas 71342SA25J

Overview

IDT71342SA25J from Integrated Device Technology is a high-speed 4K × 8 dual-port static RAM with on-chip semaphore logic, operating at 25 ns max access time over industrial temperature (–40°C to +85°C), powered by single 5V ±10% supply, and delivering 700 mW typical active power. It enables concurrent asynchronous read/write access from left and right ports for real-time interprocessor communication in embedded control systems.

For engineers reviewing the IDT71342SA25J datasheet, IDT71342SA25J pinout, IDT71342SA25J application, or IDT71342SA25J equivalent, this device supports deterministic port-to-port arbitration via hardware semaphores, requires no external arbitration logic, and is validated for use in dual-CPU industrial motion controllers, telecom line cards, and real-time data acquisition modules where deterministic latency and conflict-free shared memory access are critical.

Technical Context

The IDT71342SA25J implements fully independent left/right port control with separate address, data, and control lines (A0L–A11L/I/O0L–I/O7L/R/WL/CEL/OEL vs A0R–A11R/I/O0R–I/O7R/R/WR/CER/OER), enabling true asynchronous operation without bus contention. Its dedicated semaphore block uses eight binary latches (addressed via A0–A2 with SEM = VIL) that operate independently of the main 4K × 8 SRAM array.

Semaphore flags are active-low and support atomic "set-and-test" sequences: writing '0' requests the token, reading returns broadcast value across all I/O pins, and writing '1' releases it. The device guarantees resolution of simultaneous semaphore requests-only one port acquires the flag-with no wait states incurred on either side.

Key Specifications

Pinout & Package

52-pin Plastic Leaded Chip Carrier (PLCC), body size 20.0 mm × 20.0 mm × 4.3 mm, lead pitch 0.65 mm, RoHS-compliant, with 4 ground pins (pins 2, 46, 47, 52) and 2 V_CC pins (pins 3 and 48) requiring local decoupling.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1355BV33-25AC and IDT71322LA25J, the IDT71342SA25J uniquely delivers 5V-compatible 4K × 8 memory with on-die semaphore logic in PLCC-52-enabling deterministic, zero-software-overhead interprocessor synchronization unattainable with either alternative.

Availability

IDT71342SA25J is available at Aetrix Electronics and suitable for industrial motion controllers, telecom line cards, and avionics display processors requiring stable component supply across extended product lifecycles.

Supply support for IDT71342SA25J 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

Integrated Device Technology (IDT), now part of Renesas Electronics, designs high-performance timing, memory, and interface solutions for communications, computing, and industrial markets.

The IDT71342 product line targets deterministic multi-processor systems requiring hardware-accelerated memory sharing and lock-free resource arbitration-optimized for real-time control, signal processing, and packet-forwarding applications.

FAQ

What is the maximum guaranteed access time for IDT71342SA25J across its full industrial temperature range?

The IDT71342SA25J is specified for a maximum access time of 25 ns over the full industrial temperature range (–40°C to +85°C) under V_CC = 5.0 V ±10%. This value is production-tested and guaranteed per datasheet Table 9a, applying to both t_AA (address access) and t_ACE (chip enable access) parameters. The IDT71342SA25J achieves this performance using high-speed CMOS process technology without requiring derating at temperature extremes.

Does IDT71342SA25J support battery backup for data retention?

No, the IDT71342SA25J does not support battery backup or data retention below V_CC = 4.5 V. Only the LA variant (e.g., IDT71342LA25J) specifies 2.0 V data retention capability with 100 µA typical retention current. The SA suffix in IDT71342SA25J denotes standard power consumption (700 mW typical active), and its DC characteristics table explicitly omits V_DR and I_CCDR parameters-confirming absence of retention mode.

How are the eight semaphore flags addressed and controlled in IDT71342SA25J?

The eight semaphore flags in IDT71342SA25J are accessed exclusively via address pins A0–A2 while SEM is driven LOW; all other address pins (A3–A11) are ignored during semaphore operations. Each flag is written using only I/O0 (D0), with '0' requesting the token and '1' releasing it. Reads return the flag state broadcast across all eight I/O pins. Control requires coordinated assertion of SEM = VIL, CE = VIH, and appropriate R/W and OE levels per port.

Can both ports of IDT71342SA25J perform simultaneous read/write operations to the same memory location?

No-simultaneous read/write to the same non-semaphore memory location in IDT71342SA25J results in undefined data and is prohibited per functional description. The device permits concurrent access only to *different* addresses. When both ports target the same SRAM word, the outcome depends on relative timing of CE/R/W assertions and is not guaranteed. Semaphores are protected against such conflicts, but main memory requires software coordination or address partitioning to avoid corruption.

What package type is used for IDT71342SA25J, and are there thermal or mounting constraints?

IDT71342SA25J uses a 52-pin Plastic Leaded Chip Carrier (PLCC) package, designated PLG52, with dimensions 20.0 mm × 20.0 mm × 4.3 mm. It requires solder reflow per JEDEC J-STD-020, and thermal design must account for 700 mW typical active power dissipation. The package has four GND pins (2, 46, 47, 52) and two V_CC pins (3, 48), mandating low-inductance local decoupling (e.g., 100 nF X7R ceramic per V_CC pin) placed within 3 mm of respective pins.