Renesas 7008S25PFI8

Overview

IDT7008S25PFI8 from Integrated Device Technology (IDT) is a high-speed 64K × 8 true dual-port static RAM with independent left/right ports, 25 ns maximum access time (commercial grade), TTL-compatible 5V ±10% operation, and integrated semaphore/arbitration logic for inter-processor communication in real-time embedded systems.

For engineers reviewing the IDT7008S25PFI8 datasheet, IDT7008S25PFI8 pinout, IDT7008S25PFI8 application, or IDT7008S25PFI8 equivalent, key selection considerations include port-to-port contention handling via BUSY signaling, master/slave configuration using M/S pin, interrupt mailbox addressing at FFFE/FFFF, and low-power standby modes enabled by dual chip enables (CE0/CE1).

Technical Context

The IDT7008S25PFI8 implements fully asynchronous dual-port architecture with separate address, data, and control buses per port - enabling simultaneous read/write to the same memory location without collision. Its on-chip arbitration logic resolves port conflicts via push-pull BUSY flags and supports hardware semaphore signaling across eight shared flags addressed by A0–A2.

It operates in Master/Slave cascading mode using the M/S pin: as Master (M/S = VIH), BUSYL/BUSYR are outputs indicating write contention; as Slave (M/S = VIL), BUSYL/BUSYR become inputs that inhibit writes during contention. Interrupts are generated by writes to dedicated mailbox addresses (FFFE for INTL, FFFF for INTR), with flag reset handled by corresponding port reads/writes.

Key Specifications

Pinout & Package

Package: 100-pin TQFP (Thin Quad Flatpack), body size ≈14 mm × 14 mm × 1.4 mm, lead pitch 0.5 mm. Pinout validated per IDT document 3198 drw 03 (PNG100 package code).

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-25AXC and AS7C364B-25JCIN, the IDT7008S25PFI8 uniquely integrates full hardware arbitration (BUSY), semaphore, and interrupt mailbox logic in a 5 V TTL-compatible package - eliminating external glue logic and reducing BOM count in tightly coupled dual-CPU architectures.

Availability

IDT7008S25PFI8 is available at Aetrix Electronics and suitable for industrial automation, avionics subsystems, and medical imaging equipment requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature performance.

Supply support for IDT7008S25PFI8 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's dual-port SRAM portfolio targeted high-reliability embedded computing.

The IDT7008S25PFI8 belongs to IDT's high-speed dual-port SRAM product line, designed specifically for real-time inter-processor communication in industrial control, aerospace, and test instrumentation where deterministic latency and hardware-coordinated resource sharing are mandatory.

FAQ

What is the operating temperature range certified for the IDT7008S25PFI8?

The IDT7008S25PFI8 is rated for industrial temperature operation from –40°C to +85°C, as confirmed in the "Maximum Operating Temperature and Supply Voltage" table (3198 tbl 07) and explicitly stated in the Features section for selected speeds. This rating applies to the 'S' speed grade with 25 ns access time.

How does the M/S pin affect BUSY signal behavior on the IDT7008S25PFI8?

When M/S = VIH, the IDT7008S25PFI8 operates as Master: BUSYL and BUSYR are push-pull outputs that assert LOW during port contention. When M/S = VIL, it operates as Slave: BUSYL and BUSYR become inputs that internally inhibit writes when driven LOW by a Master device - enabling hierarchical arbitration in multi-device systems.

Can the IDT7008S25PFI8 support 16-bit data bus expansion, and how is it implemented?

Yes - the IDT7008S25PFI8 supports 16-bit (or wider) expansion using Master/Slave cascading. One device is configured as Master (M/S = VIH), others as Slaves (M/S = VIL). The Master's BUSY outputs control Slave write enables, allowing synchronized access across multiple devices without external logic - as described in the Functional Block Diagram and Features section.

What are the valid interrupt mailbox addresses for the IDT7008S25PFI8, and how are they cleared?

The IDT7008S25PFI8 uses FFFE_HEX to set the left port interrupt (INTL) and FFFF_HEX to set the right port interrupt (INTR). INTL is cleared by the left port reading FFFE with CEL = OEL = VIL; INTR is cleared by the right port reading FFFF with CER = OER = VIL - per Truth Table IV and Functional Description section.

Does the IDT7008S25PFI8 require external pull-up resistors on INTL/INTR or BUSY pins?

No - INTL, INTR, BUSYL, and BUSYR are push-pull (totem-pole) outputs per Note 2 on page 2 and Truth Table II. They drive HIGH/LOW actively and do not require external pull-ups. However, if interfacing with open-drain inputs, series current-limiting resistors may be needed to avoid bus contention.