Renesas 70261L35PF

Overview

IDT70261L35PF from Integrated Device Technology (IDT) is a high-speed 16K × 16 dual-port static RAM with interrupt and semaphore support, designed for real-time inter-processor communication in embedded systems. It features 35 ns read cycle time, 5 V single-supply operation, industrial temperature range (–40°C to +85°C), and 100-pin TQFP packaging. It enables simultaneous asynchronous access from left and right ports to shared memory locations - critical for lock-step control in motion controllers and digital signal processors.

For engineers reviewing the IDT70261L35PF datasheet, IDT70261L35PF pinout, IDT70261L35PF application, or IDT70261L35PF equivalent, key selection criteria include BUSY arbitration timing (tBAA ≤ 20 ns), interrupt flag set/reset latency (tINS/tINR ≤ 25 ns), low-power standby current (ISB3 = 0.2 mA typ.), and full on-chip semaphore logic supporting eight independent flags accessed via A0–A2.

Technical Context

The IDT70261L35PF implements fully asynchronous dual-port architecture with independent address, control, and I/O buses per port. Its on-chip arbitration logic resolves contention via BUSY assertion when both ports access identical addresses, with priority determined by input timing alignment (tAPS = 5 ns setup). The device supports MASTER/SLAVE cascading for 32-bit+ data width expansion using M/S pin configuration.

It integrates dedicated interrupt registers at fixed addresses (3FFE_H for INTL, 3FFF_H for INTR) and eight hardware semaphores addressed by A0–A2, writable via I/O0 and readable across all 16 I/O lines. All control signals - CE, R/W, OE, UB/LB, SEM - are TTL-compatible and operate from a single 5 V ±10% supply.

Key Specifications

Pinout & Package

Package: 100-pin Thin Quad Flatpack (TQFP), 0.5 mm pitch, body size 14 mm × 14 mm × 1.4 mm. Eight dedicated power/ground pairs ensure stable operation under fast switching loads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-55AC and R1EX24016AS0A, the IDT70261L35PF uniquely delivers industrial-grade timing (35 ns), hardware semaphore/INT logic, and 5 V TTL compatibility in a single 100-pin TQFP - eliminating external arbitration components and enabling deterministic real-time inter-processor communication.

Availability

IDT70261L35PF is available at Aetrix Electronics and suitable for motor control systems, industrial PLCs, and avionics flight computers requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature performance.

Supply support for IDT70261L35PF 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) was a fabless semiconductor company specializing in timing, memory interface, RF, and sensor solutions before its acquisition by Renesas Electronics in 2019. IDT pioneered high-performance dual-port SRAM architectures for real-time embedded systems.

The IDT70261L35PF belongs to IDT's 70261 family of dual-port SRAMs, engineered specifically for deterministic inter-processor communication in industrial automation, aerospace, and digital signal processing applications where hardware-enforced memory coherency is mandatory.

FAQ

What is the maximum operating frequency supported by the IDT70261L35PF?

The IDT70261L35PF has a 35 ns read cycle time (tRC), supporting a maximum sustained operation frequency of approximately 28.6 MHz per port. This value is derived directly from the AC Electrical Characteristics table (3039 tbl 12b), where tRC = 35 ns is specified for the "X35" speed grade under commercial conditions. No higher-frequency binning is documented for this part number.

Does the IDT70261L35PF support true simultaneous read/write to the same memory address?

Yes - the IDT70261L35PF implements true dual-port memory cells that allow simultaneous access to the same location. When contention occurs, on-chip arbitration asserts BUSY on the later-arriving port (tBAA ≤ 20 ns), blocking its write until the first access completes. This behavior is confirmed in Functional Description (p.15) and Truth Table IV (p.15).

How are the interrupt flags INTL and INTR triggered and cleared on the IDT70261L35PF?

INTL is asserted low when the right port writes to address 3FFE_H; it clears when the left port reads or writes to that same address. INTR is asserted low when the left port writes to 3FFF_H; it clears when the right port reads that address. This is defined in Truth Table III (p.14) and Functional Description (p.15).

What is the standby current consumption of the IDT70261L35PF in full power-down mode?

In full standby mode (ISB3), with both ports disabled using CMOS-level inputs (CE > VCC − 0.2 V, all inputs at rail), the IDT70261L35PF consumes 0.2 mA typical current, as specified in DC Electrical Characteristics Table 10 (3039 tbl 10) for the "L" variant at industrial temperature.

Can the IDT70261L35PF be used in a 32-bit data bus configuration?

Yes - the IDT70261L35PF supports 32-bit expansion via MASTER/SLAVE cascading. One device is configured as master (M/S = H) providing BUSY output, while another operates as slave (M/S = L) accepting BUSY input. This eliminates need for external arbitration logic, as described in Features (p.1) and Functional Block Diagram (p.1).