Renesas 71V321LA45PF8

Overview

71V321LA45PF8 from Renesas Electronics is a high-speed 3.3V 2K × 8 dual-port static RAM with on-chip interrupt logic and BUSY arbitration, designed for interprocessor communication in real-time embedded systems. It delivers 45 ns max access time, supports independent asynchronous read/write on left/right ports, and operates across industrial temperature (–40°C to +85°C) with 3.3V ±0.3V supply.

For engineers reviewing the 71V321LA45PF8 datasheet, 71V321LA45PF8 pinout, 71V321LA45PF8 application, or 71V321LA45PF8 equivalent, this page provides verified functional identity, validated PLCC-52 pin mapping, confirmed dual-port arbitration behavior, battery-backed data retention at 2V, and two rigorously cross-checked alternative parts for system-level design continuity.

Technical Context

The 71V321LA45PF8 implements fully asynchronous dual-port architecture with separate address, control, and I/O buses per port-enabling concurrent access without clock synchronization. Its on-chip arbitration logic uses address and chip-enable matching (not R/W state) to assert BUSYL/BUSYR outputs, preventing simultaneous writes to identical memory locations.

Interrupt functionality is implemented via dedicated mailbox addresses: INTL asserts when right port writes to 0x7FE; INTR asserts when left port writes to 0x7FF. Both flags are active-high totem-pole outputs, requiring no external pull-ups, and support software-triggered inter-processor signaling without polling overhead.

Key Specifications

Pinout & Package

71V321LA45PF8 is packaged in a 52-pin Plastic Leaded Chip Carrier (PLCC, code PLG52), body size ≈ 19.05 mm × 19.05 mm × 4.32 mm, with J-lead configuration and lead finish compliant with RoHS green standards.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1371DV33-133AXC and AS7C33128PFSIG, the 71V321LA45PF8 uniquely integrates hardware arbitration and mailbox interrupts in a compact 52-pin PLCC package-delivering deterministic sub-45 ns inter-core coordination without external logic or software overhead.

Availability

71V321LA45PF8 is available at Aetrix Electronics and suitable for industrial PLC communication modules, avionics flight control systems, telecom baseband processors, and medical imaging frame buffers requiring stable component supply across extended product lifecycles.

Supply support for 71V321LA45PF8 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

Renesas Electronics Corporation is a global semiconductor leader specializing in microcontrollers, analog, power, and memory solutions for automotive, industrial, and infrastructure markets.

The 71V321LA45PF8 belongs to Renesas' legacy dual-port SRAM family, engineered specifically for deterministic interprocessor communication in hard real-time systems where hardware-enforced memory coherency is mandatory.

FAQ

What is the exact memory capacity and organization of the 71V321LA45PF8?

The 71V321LA45PF8 provides 2K × 8 bits (2048 words × 8-bit wide), totaling 16,384 bits of static RAM. Its dual-port architecture allocates identical 11-bit address spaces (A0L–A10L and A0R–A10R) to left and right ports, enabling independent access to any location without internal contention unless addresses match.

Does the 71V321LA45PF8 support true hardware arbitration, and how does BUSY behave during address conflicts?

Yes, the 71V321LA45PF8 implements hardware arbitration via BUSYL and BUSYR outputs. When both ports assert CE and present identical addresses (A0–A10), the BUSY output on the later-arriving port goes low, internally inhibiting write operations on that side until the first access completes-guaranteeing atomic memory updates without software intervention.

How do the interrupt flags INTL and INTR operate in the 71V321LA45PF8?

INTL is asserted high when the right port writes to address 0x7FE; INTR is asserted high when the left port writes to 0x7FF. Both flags remain latched until cleared by a read access to their respective mailbox addresses. These are totem-pole outputs-no external pull-ups required-and provide hardware-triggered inter-processor signaling with sub-25 ns set/reset timing.

What is the minimum supply voltage for data retention in the 71V321LA45PF8, and what current does it draw?

The 71V321LA45PF8 retains stored data at V_CC ≥ 2.0 V. Under data retention conditions (V_CC = 2.0 V, CE held high), it draws ≤500 µA typical current-verified per datasheet Table 7-enabling reliable backup operation from coin-cell or supercapacitor sources during main power failure.

Is the 71V321LA45PF8 pin-compatible with other speed grades or package variants in the same family?

Yes, all 71V321L variants-including 25 ns, 35 ns, and 45 ns speed grades-share identical 52-pin PLCC (PLG52) pinout and electrical interface. The suffix "A45" in 71V321LA45PF8 explicitly denotes the 45 ns access time grade, while "PF8" indicates tape-and-reel packaging; no PCB layout change is needed when migrating between speed grades within the PLCC package.