Renesas 70V261S25PF

Overview

70V261S25PF from IDT is a high-speed 3.3V 16K × 16 true dual-port static RAM with independent left/right ports, 25 ns max access time (commercial/industrial), integrated BUSY arbitration logic, semaphore signaling, and interrupt flag support - used in real-time inter-processor communication systems requiring concurrent memory access without external logic.

For engineers reviewing the 70V261S25PF datasheet, 70V261S25PF pinout, 70V261S25PF application, or 70V261S25PF equivalent, this page delivers verified functional identity, validated pin roles, confirmed timing specs (tAA = 25 ns, tRC = 25 ns), power metrics (300 mW active, 3.3 mW standby), and exact package mapping to 100-pin TQFP for immediate schematic and layout integration.

Technical Context

The 70V261S25PF implements fully asynchronous dual-port architecture with separate address, control, and I/O buses per port - enabling simultaneous read/write to the same memory location only when semaphore or BUSY arbitration resolves contention. Its on-chip hardware arbitration uses chip enable (CEL/CER) and address match detection (A0–A13) to assert BUSYL/BUSYR within 25 ns (tBAA), independent of R/W state.

It integrates three coexisting coordination mechanisms: (1) push-pull BUSY outputs (MASTER mode) or inputs (SLAVE mode) controlled by M/S pin; (2) eight dedicated semaphore flags (A0–A2) accessed via SEM = VIL, CE = VIH; and (3) interrupt flags (INTL/INTR) triggered at fixed addresses (3FFEh/3FFFh) with tINS ≤ 25 ns and tINR ≤ 30 ns.

Key Specifications

Pinout & Package

70V261S25PF is housed in a 100-pin Thin Quad Flatpack (TQFP) with 0.5 mm pitch, body size 14 mm × 14 mm × 1.4 mm. All VCC and GND pins must be connected per datasheet note; N/C pins are internally unconnected and must remain floating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1362BV33-25BGXI and IDT70V3609S25PF, the 70V261S25PF uniquely integrates hardware BUSY arbitration, eight semaphores, and interrupt flags in a 16K × 16 configuration - eliminating external logic, reducing BOM count, and enabling deterministic real-time inter-processor synchronization without software overhead.

Availability

70V261S25PF is available at Aetrix Electronics and suitable for industrial PLCs, avionics data concentrators, and medical imaging pipelines requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature range (-40°C to +85°C).

Supply support for 70V261S25PF 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

IDT (Integrated Device Technology), now part of Renesas Electronics, is a semiconductor company specializing in high-performance timing, memory, and interface solutions for communications, computing, and industrial markets.

The 70V261S25PF belongs to IDT's high-speed dual-port SRAM product line, designed specifically for deterministic inter-processor communication in real-time embedded systems where hardware-coordinated memory access eliminates software arbitration bottlenecks.

FAQ

What is the maximum operating temperature range for the 70V261S25PF?

The 70V261S25PF is qualified for industrial temperature operation from −40°C to +85°C. This rating is explicitly confirmed in the DC Electrical Characteristics table (Table 05) and applies to all speed grades including the 25 ns version. No derating is required within this range, and the 25 ns access time specification remains valid across the full industrial temperature span.

Does the 70V261S25PF support true simultaneous read/write to the same memory address?

Yes, the 70V261S25PF supports true simultaneous access to the same memory location - but only when using its integrated arbitration mechanisms. If both ports attempt a write or read/write to identical addresses, BUSY logic asserts within 25 ns (tBAA) to gate one write path. Semaphores provide atomic locking for coordinated access, ensuring deterministic behavior without data corruption.

How does the M/S pin affect BUSY pin functionality on the 70V261S25PF?

When M/S = VIH, the 70V261S25PF operates as a MASTER: BUSYL and BUSYR are push-pull outputs that indicate address contention. When M/S = VIL, it operates as a SLAVE: BUSYL and BUSYR become inputs that inhibit writes when driven low. This dual-mode capability enables scalable width expansion - one master arbitrates, multiple slaves obey the BUSY signal.

What are the exact conditions to trigger the INTL interrupt flag on the 70V261S25PF?

The INTL flag is asserted when the right port performs a write to memory address 3FFEh (hex), with CER = VIL and R/WR = VIL - as defined in Truth Table III. The flag remains asserted until the left port reads address 3FFEh with CEL = VIL and OEL = VIL. This mailbox mechanism enables hardware-synchronized inter-processor signaling with ≤25 ns interrupt set time (tINS).

Can the 70V261S25PF be used in a 32-bit data bus configuration?

Yes, the 70V261S25PF supports 32-bit expansion via its Master/Slave architecture. One device is configured as MASTER (M/S = VIH) to generate BUSY arbitration signals, while additional devices operate as SLAVES (M/S = VIL) accepting BUSY as a write-inhibit input. This configuration enables full-speed, error-free 32-bit-or-wider word systems without external logic, as confirmed in the Functional Description section.