Renesas IDT7208L35P

Overview

IDT7208L35P from Integrated Device Technology is a 65,536 × 9-bit CMOS asynchronous FIFO memory buffer with 35 ns access time, designed for high-reliability rate buffering and data flow synchronization in multiprocessing systems. It features dual-port operation, retransmit capability, and status flags (Empty, Full, Half-Full) to prevent overflow/underflow. Used in industrial communication gateways requiring deterministic latency and depth-expansion support.

For engineers reviewing the IDT7208L35P datasheet, IDT7208L35P pinout, IDT7208L35P application, or IDT7208L35P equivalent, key selection criteria include its 65K×9 depth, 35 ns t_A, 5 V single-supply operation, PLASTIC DIP (P28-1) package, and compatibility with width/depth expansion architectures for scalable buffering.

Technical Context

The IDT7208L35P implements a fully asynchronous dual-port architecture with independent read/write clocks, enabling simultaneous data ingestion and egress without timing coordination. Its internal pointer logic manages FIFO state autonomously, using EF, FF, and XO/HF flags to signal boundary conditions and daisy-chain readiness.

It supports three operational modes: Single Device (XI grounded), Depth Expansion (XO→XI chaining), and Width Expansion (parallel device stacking). Retransmit (RT) resets the read pointer without affecting write position, while FL/RT dual-function pin enables first-load initialization in cascaded configurations.

Key Specifications

Pinout & Package

Package: PLASTIC DIP (P28-1), 28-pin through-hole, 0.6-inch width, RoHS-compliant lead finish (SnPb EOL; green variants available).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar FIFO memory applications.

Compared with MC100E131FN and 72V2113L15PF, the IDT7208L35P uniquely delivers 65K×9 depth, true asynchronous operation, retransmit capability, and commercial-temperature 5 V compatibility - making it irreplaceable in retrofitting legacy industrial controllers without redesigning power or clock trees.

Availability

IDT7208L35P is available at Aetrix Electronics and suitable for industrial protocol gateways, legacy system interfacing, telecom line card buffering, and military data link interfaces requiring stable component supply across extended product lifecycles.

Supply support for IDT7208L35P 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), now part of Renesas Electronics, is a fabless semiconductor company specializing in timing, memory interface, and RF power solutions for communications and computing markets.

The IDT7200 family was engineered specifically for high-reliability asynchronous data buffering in mission-critical systems - emphasizing pin-compatible scalability, MIL-STD-883 qualification, and robust flag signaling for real-time OS integration.

FAQ

What is the memory organization and access time of the IDT7208L35P?

The IDT7208L35P is organized as 65,536 words × 9 bits, providing 589,824 bits of asynchronous FIFO storage. Its maximum access time (t_A) is 35 ns under commercial temperature conditions (0°C to +70°C) at V_CC = 5.0 V ±10%. This timing ensures compatibility with 25–30 MHz microcontroller buses and legacy peripheral interfaces without wait states.

Does the IDT7208L35P support depth expansion, and how is it implemented?

Yes, the IDT7208L35P supports depth expansion via its XI (Expansion In) and XO/HF (Expansion Out) pins. In depth expansion mode, the XO output of one device connects to the XI input of the next, forming a daisy chain. The FL/RT pin must be grounded on the first device and pulled high on subsequent devices. External logic ORs all EF and FF signals to generate composite flags.

What is the function of the FL/RT pin on the IDT7208L35P?

The FL/RT pin on the IDT7208L35P serves a dual role: as First Load (FL) in depth expansion mode to designate the initial device in a chain, and as Retransmit (RT) in single-device mode to reset the read pointer to location zero without altering the write pointer. A low pulse ≥35 ns triggers retransmit, enabling repeat-read functionality for packet retransmission or diagnostic replay.

What package type and pin count does the IDT7208L35P use?

The IDT7208L35P uses a PLASTIC DIP (P28-1) package - a 28-pin, 0.6-inch wide, through-hole dual in-line package. It is RoHS-compliant with SnPb lead finish (currently in EOL process; green variants available). Pin layout matches industry-standard 28-DIP footprints, enabling direct replacement in legacy industrial PCBs.

How does the IDT7208L35P handle power management in low-power systems?

The IDT7208L35P supports three power states: Active (max 660 mW), Standby (max 12 mA ICC2), and Power-down (max 2 mA ICC3). Power-down is entered when RS, W, R, and FL/RT are held high; it reduces current draw by >95% versus active mode. Recovery time from power-down is ≤35 ns, preserving real-time responsiveness in duty-cycled systems.