Renesas 70261L15PFI8

Overview

70261L15PFI8 from IDT (Integrated Device Technology) is a high-speed 16K × 16 true dual-port static RAM with interrupt and semaphore logic, operating at 15 ns max access time (commercial grade), 5 V ±10% supply, and industrial temperature range (−40°C to +85°C). It supports independent asynchronous read/write on left and right ports, full on-chip arbitration, and is used in real-time interprocessor communication systems requiring deterministic memory access.

For engineers reviewing the 70261L15PFI8 datasheet, 70261L15PFI8 pinout, 70261L15PFI8 application, or 70261L15PFI8 equivalent, key selection criteria include port-to-port contention resolution timing (tBDD ≤ 18 ns), low standby power (1 mW typ.), 100-pin TQFP package compatibility, and interrupt mailbox addressing at 3FFE/3FFF hex.

Technical Context

The 70261L15PFI8 implements fully asynchronous dual-port architecture with separate address, control, and I/O buses per port. Its on-chip arbitration logic resolves simultaneous accesses to identical addresses using BUSY flag assertion (M/S = VIH for master output; M/S = VIL for slave input), with tAPS = 5 ns priority setup time and tBDD ≤ 18 ns disable-to-valid-data delay.

It integrates dedicated semaphore registers (8 flags, addressed via A0–A2), interrupt generation via dedicated mailbox addresses (3FFE for INTL, 3FFF for INTR), and byte-selectable I/O (UBL/LBL, UBR/LBR) enabling multiplexed bus interfacing and seamless 32-bit expansion via MASTER/SLAVE cascading.

Key Specifications

Pinout & Package

70261L15PFI8 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 externally decoupled per layout guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1362BV33-15ZXI and IDT70V261S15PFI, the 70261L15PFI8 uniquely delivers industrial temperature support, sub-mW standby, and fully integrated interrupt/semaphore hardware - reducing BOM count and firmware complexity in rugged embedded systems.

Availability

70261L15PFI8 is available at Aetrix Electronics and suitable for industrial PLC communication modules, real-time motor drive controllers, avionics data concentrators, and medical imaging signal processors requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 70261L15PFI8 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 fabless semiconductor company specializing in timing, memory interface, RF, and high-performance silicon solutions for communications, computing, and industrial markets.

The IDT70261 product line was designed specifically for deterministic interprocessor communication in real-time embedded systems, integrating dual-port memory, hardware arbitration, interrupt mailboxes, and semaphore logic into a single 5 V-compatible device.

FAQ

What is the maximum operating temperature range for the 70261L15PFI8?

The 70261L15PFI8 is rated for industrial temperature operation from −40°C to +85°C. This specification is confirmed in the "Maximum Operating Temperature and Supply Voltage" table (Table 2) and applies to all speed grades of the IDT70261L family, including the 15 ns version. The device maintains full functionality and timing compliance across this range under 5.0 V ±10% supply conditions.

Does the 70261L15PFI8 support true simultaneous access to the same memory location?

Yes, the 70261L15PFI8 implements true dual-ported memory cells that allow simultaneous read/write access to identical addresses. When contention occurs, on-chip arbitration asserts BUSY on the losing port within tBAC ≤ 15 ns (M/S = VIH), blocking its write until BUSY deasserts - ensuring data integrity without external logic. This behavior is documented in Truth Table IV and the BUSY Timing section (Table 14a).

How does the interrupt function work on the 70261L15PFI8?

The 70261L15PFI8 uses fixed-address mailboxes: writing to address 3FFF (HEX) on the left port asserts INTR; writing to 3FFE on the right port asserts INTL. Clearing is performed by reading those same addresses. Timing is guaranteed with tINS ≤ 15 ns and tINR ≤ 15 ns (Table 15a). These locations remain usable as general SRAM if interrupts are unused.

What is the standby current consumption of the 70261L15PFI8?

The 70261L15PFI8 exhibits 1 mW typical standby power (ISB3 = 0.2 mA at VCC = 5 V), per DC Electrical Characteristics (Table 10). This ultra-low value is achieved when both ports are disabled (CEL = CER = VIH) and all inputs are CMOS-level stable - making it ideal for battery-backed or energy-sensitive industrial nodes.

Can the 70261L15PFI8 be used in a 32-bit memory system?

Yes, the 70261L15PFI8 supports 32-bit expansion via MASTER/SLAVE cascading. When configured as MASTER (M/S = H), BUSY is an output; as SLAVE (M/S = L), BUSY is an input. Two devices can be connected back-to-back using BUSY handshake and CE synchronization to form a coherent 32-bit-wide memory without additional logic, as described in the Functional Description and Pin Configuration sections.