Texas Instruments SN74ACT7204L20NP

Overview

SN74ACT7204L20NP from Texas Instruments is a 4096 × 9-bit asynchronous dual-port FIFO memory IC with independent read/write address counters, 15 ns data access time, 40 MHz operation, and TTL-compatible inputs. It functions as a first-in-first-out data buffer between asynchronous buses in embedded communication and data acquisition systems.

For engineers reviewing the SN74ACT7204L20NP datasheet, SN74ACT7204L20NP pinout, SN74ACT7204L20NP application, or SN74ACT7204L20NP equivalent, key selection criteria include its 4096-word depth, 9-bit bus width with parity support, retransmit capability, and empty/full/half-full status flags for robust flow control in real-time buffering applications.

Technical Context

This device implements a dual-port SRAM-based FIFO architecture with separate internal write and read address pointers, enabling fully asynchronous or coincident read/write operations. Its expansion logic supports both bit-width and word-depth cascading using XI/XO/HF signals.

It features dedicated status flag outputs (EF, FF, XO/HF) tied directly to pointer arithmetic - EF asserts when read pointer equals write pointer, FF asserts when write pointer is one location behind read pointer (i.e., full), and XO/HF serves as half-full flag or expansion-out signal depending on XI configuration.

Key Specifications

Pinout & Package

SN74ACT7204L20NP is supplied in a 28-pin plastic DIP (Dual In-line Package) with 0.600-inch body width and through-hole mounting.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT7204L20JI and SN74ACT7204L20DV, the SN74ACT7204L20NP offers identical core FIFO functionality and timing in a through-hole plastic DIP package optimized for prototyping, repairability, and legacy board compatibility - making it ideal for lab validation and commercial-grade fixed-installation systems.

Availability

SN74ACT7204L20NP is available at Aetrix Electronics and suitable for industrial data acquisition, communications protocol queuing, magnetic/optical storage interfaces, and legacy bus bridge buffering requiring stable component supply across long-lifecycle programs.

Supply support for SN74ACT7204L20NP 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

The SN74ACT7204L20NP belongs to TI's ACT-family advanced CMOS logic FIFO product line, designed specifically for high-reliability, low-latency data buffering in asynchronous multi-bus systems.

FAQ

What is the memory depth and width of the SN74ACT7204L20NP?

The SN74ACT7204L20NP provides a 4096 × 9-bit FIFO memory structure - meaning it stores 4096 words, each 9 bits wide. This supports 8-bit data plus parity or packet framing bits. The architecture uses dual-port SRAM with independent read and write address counters, enabling true asynchronous operation between two data streams.

Does the SN74ACT7204L20NP support retransmission of previously read data?

Yes, the SN74ACT7204L20NP supports retransmit functionality via the FL/RT pin. When configured for single-device use (XI grounded), pulsing FL/RT low resets only the internal read pointer to location zero while preserving the write pointer position. This allows previously read data to be re-output on Q0–Q8 without altering stored content - essential for protocol retry mechanisms.

How does the SN74ACT7204L20NP indicate buffer status?

The SN74ACT7204L20NP provides three dedicated status flags: EF (empty flag, active-low), FF (full flag, active-low), and XO/HF (half-full/expansion-out). EF goes low when no data is available; FF goes low when the buffer is full (4096 writes since reset); XO/HF acts as a half-full indicator (low when ≥2048 words stored) unless used in depth expansion.

Can multiple SN74ACT7204L20NP devices be cascaded for larger memory capacity?

Yes, the SN74ACT7204L20NP supports both word-width and word-depth expansion. For depth expansion, devices are daisy-chained using XI and XO/HF pins with FL/RT grounded on the first device. For width expansion, multiple units share R/W/RS/FL/RT controls while connecting D0–D8 and Q0–Q8 in parallel - enabling custom bus widths like 18-bit or 27-bit FIFOs.

What package type is used for the SN74ACT7204L20NP?

The SN74ACT7204L20NP is housed in a 28-pin plastic dual in-line package (DIP) with 0.600-inch body width and through-hole mounting. This NP package variant is optimized for breadboarding, manual assembly, field repair, and legacy board compatibility - distinct from the SOIC (DV) or PLCC (RJ) variants of the same IC.