Renesas 71342SA70J8

Overview

IDT71342SA70J8 from Integrated Device Technology is a high-speed 4K × 8 dual-port static RAM with on-chip semaphore logic, operating at 70 ns max read cycle time, supporting independent asynchronous access from left and right ports, and featuring TTL-compatible 5V ±10% supply - used in real-time interprocessor communication systems requiring concurrent memory access without software arbitration.

For engineers reviewing the IDT71342SA70J8 datasheet, IDT71342SA70J8 pinout, IDT71342SA70J8 application, or IDT71342SA70J8 equivalent, this device delivers deterministic port-to-port timing (tDDD = 70 ns), hardware semaphore contention resolution (tSPS = 10 ns), low-power standby (ISB3 = 1.0 mA typ.), and industrial-grade reliability in a 64-pin TQFP package - critical for embedded multiprocessor control, avionics data buffers, and legacy military computing upgrades.

Technical Context

The IDT71342SA70J8 implements fully asynchronous dual-port architecture with separate address, control, and I/O buses per port, enabling simultaneous read/write operations across non-semaphore memory locations. Its dedicated 3-bit semaphore address space (A0–A2) and SEM pin enable hardware-level token passing without CPU intervention.

Semaphore logic uses dual request latches per flag to guarantee atomic set/test behavior: only one port can successfully write '0' to claim a flag, and subsequent reads reflect latched state across all 8 data bits. Power-down is controlled independently per port via CE and SEM high states, achieving ISB3 = 1.0 mA typical with CMOS-level inputs.

Key Specifications

Pinout & Package

Package: 64-pin TQFP (PNG64), body size 14 mm × 14 mm × 1.4 mm, lead pitch 0.5 mm, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1362V-70AXC and AS7C34098B-70JCIN, IDT71342SA70J8 uniquely integrates certified 10 ns semaphore arbitration and consumes 60% less standby current in full sleep mode - directly reducing thermal design margin and qualification risk in convection-cooled enclosures.

Availability

IDT71342SA70J8 is available at Aetrix Electronics and suitable for avionics flight control buffers, military radar signal processors, industrial PLC redundancy modules, and legacy telecom switch fabrics requiring stable component supply across extended production lifecycles.

Supply support for IDT71342SA70J8 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 demanding embedded and communications systems.

IDT71342SA70J8 belongs to the IDT71342 dual-port SRAM family, engineered specifically for deterministic interprocessor communication in real-time control systems where software arbitration introduces unacceptable latency.

FAQ

What is the maximum operating temperature range for IDT71342SA70J8?

IDT71342SA70J8 is rated for commercial temperature range only: 0°C to +70°C. It is not qualified for industrial (–40°C to +85°C) operation - that capability is reserved for LA-suffix variants like IDT71342LA70J8. The 'SA' suffix explicitly denotes commercial-grade speed/power binning and thermal rating.

Does IDT71342SA70J8 support battery backup for data retention?

No, IDT71342SA70J8 does not support battery backup data retention. That feature is exclusive to LA-suffix versions (e.g., IDT71342LA70J8), which specify VDR = 2.0 V minimum and ICCDR ≤ 1500 µA at 2 V. The SA variant lacks the internal circuitry for low-voltage retention mode.

How many semaphore flags does IDT71342SA70J8 provide, and how are they addressed?

IDT71342SA70J8 provides eight independent binary semaphore flags, accessed exclusively via A0–A2 address lines while SEM is asserted low. All other address bits (A3–A11) are ignored during semaphore access, and only I/O0 is used for writing flag state (0 = claim, 1 = release).

What is the function of the SEM pin on IDT71342SA70J8?

The SEM pin on IDT71342SA70J8 is an active-low semaphore select input. When SEM = VIH, the device operates as standard dual-port RAM using A0–A11. When SEM = VIL, the address space switches to the 8-location semaphore register bank (A0–A2 only), disabling normal RAM access until SEM returns high.

Can both ports of IDT71342SA70J8 perform simultaneous writes to the same memory location?

No - simultaneous writes to the same non-semaphore memory location by both ports result in undefined data and potential bus contention. The datasheet explicitly warns that conflict arises only during simultaneous WRITE or READ/WRITE to identical addresses. Semaphore locations are protected against such ambiguity via dedicated arbitration logic.