Renesas 7130SA55PF8

Overview

7130SA55PF8 from IDT is a high-speed 1K × 8 dual-port static RAM configured as a MASTER device with on-chip arbitration logic, 55 ns maximum read/write cycle time, open-drain BUSY outputs requiring external pull-up resistors, and TTL-compatible 5 V ±10% operation - used in real-time inter-processor communication systems where simultaneous access from two independent buses must be resolved without external logic.

For engineers reviewing the 7130SA55PF8 datasheet, 7130SA55PF8 pinout, 7130SA55PF8 application, or 7130SA55PF8 equivalent, key selection criteria include its 55 ns access timing, dual-port arbitration capability, BUSY flag behavior for contention resolution, and compatibility with IDT7140SLAVE devices in 16-bit memory expansion architectures.

Technical Context

The 7130SA55PF8 implements fully asynchronous dual-port operation with independent left/right address, control, and I/O buses. Its on-chip arbitration logic resolves port conflicts via BUSYL/BUSYR open-drain flags, with tAPS = 5 ns priority setup time ensuring deterministic contention resolution.

It supports R/W-controlled and CE-controlled write cycles, features INTL/INTR interrupt signaling for port-to-port notification, and maintains data integrity during simultaneous access using tBDD (BUSY disable to valid data) ≤35 ns at 55 ns speed grade - critical for deterministic real-time embedded memory subsystems.

Key Specifications

Pinout & Package

7130SA55PF8 is supplied in a 48-pin ceramic flatpack (FP48) package measuring approximately 0.75 in × 0.75 in × 0.11 in, with through-hole mounting and side-braze construction for high-reliability military/industrial use.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C131-55JC and IDT7140SA55PF8, the 7130SA55PF8 uniquely delivers self-contained arbitration and interrupt signaling in a single MASTER device - reducing BOM count and PCB area while guaranteeing deterministic behavior in real-time dual-processor systems.

Availability

7130SA55PF8 is available at Aetrix Electronics and suitable for real-time inter-processor communication, digital signal processing buffering, and industrial PLC memory coherency requiring stable component supply across extended product lifecycles.

Supply support for 7130SA55PF8 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) is a semiconductor company specializing in timing, memory interface, and RF solutions, now part of Renesas Electronics.

The IDT7130 product line was engineered for deterministic dual-processor memory sharing in industrial, military, and telecom infrastructure - emphasizing hardware arbitration, low-latency access, and rugged packaging.

FAQ

What is the function of BUSYL and BUSYR on the 7130SA55PF8?

BUSYL and BUSYR are open-drain outputs on the 7130SA55PF8 that signal port contention. When the opposite port initiates a write to the same memory address, the corresponding BUSY pin is pulled LOW (requiring an external pull-up resistor). This inhibits writes on the asserting port until BUSY returns HIGH, ensuring data coherency without software intervention. The 7130SA55PF8 implements this as part of its MASTER arbitration logic.

Can the 7130SA55PF8 operate with a 3.3 V supply?

No, the 7130SA55PF8 requires a 5 V ±10% supply (4.5 V to 5.5 V) and is TTL-compatible only. It does not support 3.3 V operation. Attempting to power it from 3.3 V will result in undefined behavior, failure to meet timing specifications, and potential data retention loss. For 3.3 V systems, a level-shifting interface or alternative low-voltage dual-port SRAM must be used alongside the 7130SA55PF8.

How does the 7130SA55PF8 handle simultaneous read and write to the same address?

When both ports access the same address concurrently, the 7130SA55PF8 uses its on-chip arbitration logic to grant priority based on timing - specifically the arbitration priority setup time (tAPS = 5 ns). The port satisfying tAPS first proceeds; the other port's BUSY flag asserts LOW, blocking its write. Read operations remain valid, but writes are inhibited until BUSY deasserts. This behavior is guaranteed by the 7130SA55PF8's hardware design and requires no external logic.

What is the purpose of the INTL and INTR pins on the 7130SA55PF8?

INTL and INTR are active-low interrupt outputs on the 7130SA55PF8 used for port-to-port event signaling. Writing to specific addresses (e.g., 3FFh on left port sets INTR; 3FEh on right port clears INTL) triggers these flags. They enable lock-free, hardware-accelerated inter-processor communication - for example, notifying a host MCU that new sensor data is ready in memory. This eliminates polling overhead and reduces latency compared to status-register polling in the 7130SA55PF8.

Is the 7130SA55PF8 pin-compatible with the IDT7140 series?

No, the 7130SA55PF8 is not pin-compatible with IDT7140 devices despite identical package and pin count. While both use 48-pin FP48, BUSYL/BUSYR are outputs on the 7130SA55PF8 but inputs on IDT7140 SLAVE devices, and INTL/INTR functionality differs. Interchanging them without redesigning the PCB and firmware will cause functional failure. The 7130SA55PF8 and IDT7140SA55PF8 are complementary (MASTER/SLAVE), not drop-in replacements.