Renesas 71342LA25PFGI8

Overview

IDT71342LA25PFGI8 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, 5 V ±10% supply, and industrial temperature range (–40°C to +85°C). It supports fully asynchronous dual-port reads/writes and battery-backed data retention down to 2 V. Used in real-time interprocessor communication systems requiring concurrent memory access without arbitration wait states.

For engineers reviewing the IDT71342LA25PFGI8 datasheet, IDT71342LA25PFGI8 pinout, IDT71342LA25PFGI8 application, or IDT71342LA25PFGI8 equivalent, key selection criteria include dual-port timing isolation, hardware semaphore flag behavior, 2 V data retention capability, TTL-compatible I/O, and PLCC-52 package compatibility for legacy industrial control designs.

Technical Context

The IDT71342LA25PFGI8 implements two fully independent asynchronous ports-left (L) and right (R)-each with dedicated address (A0L–A11L / A0R–A11R), data (I/O0L–I/O7L / I/O0R–I/O7R), and control lines (CEL/CER, OEL/OER, R/WL/R/WR). Memory array size is exactly 4,096 × 8 bits, with eight dedicated semaphore flag locations accessed via A0–A2 under SEM = VIL.

Semaphore logic consists of eight independent latches, each active-low and write-locked per port: writing '0' to a flag grants exclusive token ownership to that port; writing '1' releases it. Flag reads return uniform values across all 8 I/O pins, latched on SEM+OE activation to prevent mid-cycle corruption during cross-port writes.

Key Specifications

Pinout & Package

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, lead-free finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1342KV18-25BGXI and IDT71V3577SA85BG, the IDT71342LA25PFGI8 uniquely delivers 5 V TTL compatibility, 2 V battery retention, and integrated semaphores in a legacy-friendly PLCC-52 package - making it irreplaceable for sustaining industrial control and avionics upgrades without PCB redesign.

Availability

IDT71342LA25PFGI8 is available at Aetrix Electronics and suitable for industrial PLCs, telecom line cards, avionics sensor modules, and medical imaging pipelines requiring stable component supply across extended product lifecycles.

Supply support for IDT71342LA25PFGI8 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, is a fabless semiconductor company specializing in timing, memory interface, and RF power solutions for high-performance computing and communications infrastructure.

IDT71342LA25PFGI8 belongs to IDT's legacy dual-port SRAM product line, designed specifically for deterministic interprocessor communication in real-time embedded systems where hardware semaphore arbitration eliminates software-induced latency and deadlock risk.

FAQ

What is the maximum guaranteed access time for IDT71342LA25PFGI8 across its full industrial temperature range?

IDT71342LA25PFGI8 guarantees a maximum access time of 25 ns over the full industrial temperature range (–40°C to +85°C) and supply voltage range (4.5 V to 5.5 V). This value is production-tested and specified in the AC Electrical Characteristics table for the "71342X25" speed grade. It applies to both read cycle time (tRC) and address access time (tAA), ensuring deterministic timing for hard real-time systems.

Does IDT71342LA25PFGI8 support true simultaneous read/write operations between ports without conflict?

IDT71342LA25PFGI8 supports fully independent asynchronous access: one port can read while the other writes to a different memory location with no timing penalty. However, simultaneous read/write to the *same* non-semaphore address causes undefined data - the device does not resolve such conflicts. Semaphore flag locations are protected against this; only one port may write to a given flag at a time, enforced by hardware lock logic.

How does the semaphore flag mechanism work in IDT71342LA25PFGI8, and what happens during simultaneous requests?

In IDT71342LA25PFGI8, semaphore flags are eight independent latches addressed via A0–A2 when SEM = VIL. Writing '0' grants exclusive token ownership to that port; writing '1' releases it. If both ports attempt to write '0' simultaneously, the hardware guarantees only one succeeds - the first to meet setup timing wins; if perfectly aligned, assignment is deterministic but arbitrary. No bus lock or retry logic is needed.

Can IDT71342LA25PFGI8 retain data when main VCC drops below 4.5 V, and what is the minimum retention voltage?

Yes - IDT71342LA25PFGI8 supports battery backup data retention at VCC as low as 2.0 V (typical), with ICCDR ≤ 1500 µA. This is a feature exclusive to the 'LA' variant (low-power version). Retention mode activates automatically when CE and SEM are both high and VCC falls within 2.0–4.5 V; data remains valid indefinitely as long as VCC ≥ 2.0 V and temperature stays within specification.

What package type and pin count does IDT71342LA25PFGI8 use, and are there alternate packages for this speed grade?

IDT71342LA25PFGI8 uses a 52-pin Plastic Leaded Chip Carrier (PLCC) package, designated 'PFGI8' in the part number. While the IDT71342 family also offers a 64-pin TQFP (PNG64) option, the '25' speed grade (25 ns) is only available in the PLCC-52 variant per the datasheet ordering information - no TQFP version exists for this specific timing grade.