Renesas 70V24S20PFI

Overview

70V24S20PFI from Integrated Device Technology is a high-speed 4K x 16 dual-port static RAM with independent left/right asynchronous ports, 20 ns maximum access time (industrial grade), 3.3 V ±0.3 V single supply, and on-chip semaphore arbitration logic. It supports simultaneous read/write operations across ports and is used in real-time inter-processor communication systems requiring deterministic latency and collision-free shared memory access.

For engineers reviewing the 70V24S20PFI datasheet, 70V24S20PFI pinout, 70V24S20PFI application, or 70V24S20PFI equivalent, key selection criteria include industrial temperature support (–40°C to +85°C), 84-pin PLCC package compatibility, true dual-port bus arbitration, and low-power standby current of 13 mA (typ.) under TTL-level inputs.

Technical Context

The 70V24S20PFI implements fully asynchronous dual-port architecture with separate address, control, and I/O buses per port. Its on-chip arbitration logic resolves contention via BUSY flag signaling and master/slave configuration using the M/S pin, enabling cascaded 32-bit+ memory expansion without external logic.

It integrates full hardware semaphore support-eight flags addressed by A0–A2-with dedicated SEM pins and defined timing windows (tSPS = 5 ns, tSWRD = 5 ns) for atomic read-modify-write operations between ports, ensuring deterministic inter-process synchronization in embedded control applications.

Key Specifications

Pinout & Package

70V24S20PFI is housed in an 84-pin Plastic Leaded Chip Carrier (PLCC, package code PLG84), measuring approximately 1.15 in × 1.15 in × 0.17 in, with gull-wing leads and internal heat slug for thermal stability in continuous operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C024AV-20AXC and IDT70V24L15PF, the 70V24S20PFI uniquely combines industrial temperature rating, 84-pin PLCC packaging, and 20 ns access in a single device-making it the only drop-in solution for legacy through-hole industrial designs requiring guaranteed –40°C to +85°C operation without layout change.

Availability

70V24S20PFI is available at Aetrix Electronics and suitable for motor control systems, industrial PLC backplanes, digital signal processing subsystems, and avionics data concentrators requiring stable component supply across extended product lifecycles.

Supply support for 70V24S20PFI 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, RF, and high-performance silicon solutions.

The IDT70V24 family was designed specifically for deterministic inter-processor communication in industrial automation and real-time embedded systems, emphasizing hardware arbitration, low-latency access, and ruggedized packaging.

FAQ

What is the maximum operating temperature range supported by the 70V24S20PFI?

The 70V24S20PFI is rated for industrial temperature operation from –40°C to +85°C. This specification is guaranteed across all electrical parameters including 20 ns maximum access time and standby current limits, making it suitable for deployment in harsh environments such as factory floors, outdoor control cabinets, and transportation equipment without thermal derating.

Does the 70V24S20PFI support true simultaneous read operations from both ports to the same memory location?

Yes, the 70V24S20PFI implements true dual-port SRAM cells that allow concurrent reads from both left and right ports to identical addresses without conflict or performance penalty. This capability is fundamental to its use in real-time inter-processor communication where synchronized data visibility is required, and is explicitly confirmed in the device's functional description and truth tables.

How does the M/S pin configure master/slave behavior in cascaded 70V24S20PFI systems?

When M/S = VIH, the 70V24S20PFI operates as master with BUSYR functioning as an output flag; when M/S = VIL, it operates as slave with BUSYR configured as an input. This enables daisy-chained configurations where the master asserts BUSY to stall slaves during contention, allowing seamless expansion to 32-bit or wider data buses without external arbitration logic.

What is the function of the SEM pins on the 70V24S20PFI and how are semaphores accessed?

The SEML and SEMR pins enable hardware semaphore register access. When SEM = VIL and CE = VIH (or UB & LB = VIH), the eight semaphore flags-addressed by A0–A2-are read from or written via I/O0, with all I/O lines reflecting the flag value. This provides atomic, lock-free synchronization between ports with guaranteed tSPS = 5 ns contention window and tSWRD = 5 ns write-to-read delay.

Is the 70V24S20PFI pin-compatible with other members of the IDT70V24 family such as the 70V24L15PF?

Yes, the 70V24S20PFI shares identical 84-pin PLCC pinout and signal mapping with all IDT70V24 variants including 70V24L15PF. Differences are limited to speed grade (20 ns vs. 15 ns), power profile (S vs. L), and temperature rating (industrial vs. commercial), allowing direct substitution in existing layouts when electrical and thermal requirements align.