Renesas 70V24S35PFI

Overview

70V24S35PFI from Integrated Device Technology (IDT) is a high-speed 3.3V 4K × 16 true dual-port static RAM with independent left/right ports, 35 ns maximum read cycle time, industrial temperature range (–40°C to +85°C), and 84-pin PLCC package. It enables simultaneous asynchronous access for real-time inter-processor communication in embedded control systems.

For engineers reviewing the 70V24S35PFI datasheet, 70V24S35PFI pinout, 70V24S35PFI application, or 70V24S35PFI equivalent, key selection criteria include dual-port arbitration logic, semaphore flag support, BUSY/INT signaling, byte-selectable I/O (UBL/LBL), and low-power standby operation at 660 μW typical.

Technical Context

The 70V24S35PFI implements fully asynchronous dual-port architecture with on-chip port arbitration and hardware semaphore logic-eight flags addressable via A0–A2, writable via I/O0 and readable across all data pins. It supports MASTER/SLAVE cascading for 32-bit+ bus expansion using M/S pin control.

Each port features independent CE, R/W, OE, UB/LB, and SEM controls; BUSY is output on MASTER and input on SLAVE. The device operates from a single 3.3 V ±0.3 V supply and uses CMOS process technology for 400 mW typical active power consumption.

Key Specifications

Pinout & Package

70V24S35PFI is housed in an 84-pin Plastic Leaded Chip Carrier (PLCC, package code PLG84), body size ≈ 1.15 in × 1.15 in × 0.17 in, with gull-wing leads and internal heat slug. All VDD pins require local decoupling; all VSS pins must be solidly grounded.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C024AV-35AXC and IDT70V25S35PF, the 70V24S35PFI uniquely delivers industrial temperature qualification, 84-pin PLCC mechanical robustness, and integrated BUSY/INT signaling-enabling drop-in deployment in mission-critical systems where reliability and deterministic arbitration are mandatory.

Availability

70V24S35PFI is available at Aetrix Electronics and suitable for industrial PLC communication modules, avionics data acquisition units, and medical imaging real-time buffers requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for 70V24S35PFI 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 power management ICs for communications, computing, and industrial markets.

The IDT70V24 product line delivers high-speed, low-power dual-port SRAMs optimized for real-time inter-processor communication, motion control, and embedded systems requiring deterministic memory access and hardware synchronization.

FAQ

What is the maximum operating frequency supported by the 70V24S35PFI?

The 70V24S35PFI has a 35 ns maximum read cycle time (tRC), supporting sustained operation up to 28.6 MHz per port. This is derived directly from tRC = 35 ns → f_MAX = 1/tRC. The device does not require clock input-it operates asynchronously, so timing is governed solely by setup/hold and access specifications, not a fixed clock rate. Actual system frequency depends on board layout, signal integrity, and control signal timing margins.

Does the 70V24S35PFI support true simultaneous read operations on both ports to the same memory location?

Yes, the 70V24S35PFI implements true dual-port SRAM cells that allow concurrent reads from both left and right ports to the exact same address without contention or data corruption. This capability is inherent to its cell architecture-not dependent on arbitration logic-and is explicitly confirmed in the datasheet's "Features" section. Simultaneous writes to the same location are prevented by BUSY flag assertion, but simultaneous reads are fully supported and deterministic.

How is semaphore functionality implemented in the 70V24S35PFI, and what are its practical use cases?

The 70V24S35PFI integrates eight hardware semaphore flags addressed by A0–A2 and controlled via SEML/SEMR. Writing to I/O0 updates the selected flag; reading returns the flag value across all I/O lines. This enables lock-free inter-processor synchronization-for example, one CPU can claim a shared resource by setting a flag before accessing it, while the other polls the flag's state. No external logic or software mutexes are needed, reducing latency and eliminating priority inversion risks in real-time systems.

Can the 70V24S35PFI be used in MASTER/SLAVE configurations, and how is this configured?

Yes, the 70V24S35PFI supports MASTER/SLAVE cascading via the M/S pin: VIH configures the device as MASTER (BUSYL asserted as output), VIL configures it as SLAVE (BUSYR accepted as input). When cascaded, the MASTER's BUSY output connects to the SLAVE's BUSY input to coordinate access across devices-enabling seamless expansion to 32-bit or wider data buses without external glue logic. Pin A12 is NC in this configuration, per datasheet Note 1.

What are the power consumption characteristics of the 70V24S35PFI in active and standby modes?

In active operation (both ports enabled), the 70V24S35PFI draws 400 mW typical (120 mA at 3.3 V). In full standby (CE high, CMOS-level inputs), it consumes just 660 μW typical-verified in Table 9b for 70V24L15/70V24X25 variants. This ultra-low standby power is achieved by internally disabling all I/O drivers and core logic while retaining memory state, making it suitable for battery-backed or energy-constrained industrial systems where memory retention during sleep is critical.