Texas Instruments SN74ACT7205L25NP

Overview

SN74ACT7205L25NP from Texas Instruments is a 8192 × 9-bit asynchronous dual-port FIFO memory IC with independent read/write operations, 15 ns access time, 40 MHz operation, and TTL-compatible inputs. It implements first-in-first-out buffering for data rate matching between asynchronous buses in communication systems and data-acquisition interfaces.

For engineers reviewing the SN74ACT7205L25NP datasheet, SN74ACT7205L25NP pinout, SN74ACT7205L25NP application, or SN74ACT7205L25NP equivalent, key selection criteria include depth-expansion capability, retransmit functionality, empty/full/half-full flag outputs, and 28-pin plastic DIP (NP) package compatibility with legacy industrial control and test equipment designs.

Technical Context

The SN74ACT7205L25NP integrates dual-port SRAM with internal write and read address counters, enabling true asynchronous or coincident read/write cycles without external arbitration logic. Its status-flag logic generates EF (empty), FF (full), and XO/HF (half-full/expansion-out) signals directly from pointer comparison.

Depth expansion is implemented via daisy-chained XI/XO connections across multiple devices, while width expansion uses parallel data bus connections with shared control lines. The FL/RT pin serves dual roles: first-load enable in depth chains and retransmit trigger when XI = GND.

Key Specifications

Pinout & Package

SN74ACT7205L25NP is packaged in a 28-pin plastic DIP (NP) with through-hole mounting and 0.6-inch body width, suitable for prototyping, legacy PCBs, and industrial backplane applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT7205L25 and SN74ACT7204L25NP, the SN74ACT7205L25NP delivers full 8192-word depth in a drop-in compatible 28-pin DIP package with ongoing TI manufacturing support, making it the optimal choice for new industrial and test-equipment designs requiring robust, long-lifecycle FIFO buffering.

Availability

SN74ACT7205L25NP is available at Aetrix Electronics and suitable for industrial data acquisition, asynchronous bus bridging, communication protocol queuing, and legacy system memory expansion requiring stable component supply and long-term design continuity.

Supply support for SN74ACT7205L25NP 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 delivering analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

The SN74ACT7205L25NP belongs to TI's ACT-family advanced CMOS FIFO product line, engineered specifically for high-reliability, 5 V-based asynchronous data buffering in industrial control, test equipment, and legacy system upgrades.

FAQ

What is the memory depth and width of the SN74ACT7205L25NP?

The SN74ACT7205L25NP provides an 8192 × 9-bit FIFO memory structure - meaning it stores up to 8192 words, each 9 bits wide. This configuration supports 8-bit data plus parity or protocol framing bits. The depth is fixed and cannot be altered without external expansion logic or cascading additional SN74ACT7205L25NP devices.

Does the SN74ACT7205L25NP support simultaneous read and write operations?

Yes, the SN74ACT7205L25NP supports fully asynchronous read and write operations - they may occur coincidentally or independently on separate clock domains. The internal dual-port SRAM and independent address counters ensure no bus contention or arbitration logic is required, enabling true concurrent access as long as EF and FF flags permit valid cycles.

How does the retransmit function work on the SN74ACT7205L25NP?

The SN74ACT7205L25NP's retransmit function is activated by pulsing the FL/RT pin low while XI is grounded and R/W are high. This resets the internal read pointer to location zero without altering the write pointer, allowing previously read data to be re-output. Retransmit is safe only if fewer than 8192 writes have occurred since the last reset to avoid overwriting unread data.

Can multiple SN74ACT7205L25NP devices be connected for greater depth?

Yes, the SN74ACT7205L25NP supports depth expansion via its XI (expansion-in) and XO/HF (expansion-out) pins. Devices are daisy-chained with XO/HF of one connected to XI of the next. The first device has FL/RT grounded; others hold FL/RT high. Composite EF/FF flags require external OR gates, and RT/HF functions are disabled in expanded configurations.

What package type is used for the SN74ACT7205L25NP?

The SN74ACT7205L25NP uses a 28-pin plastic dual-inline-package (DIP) with NP suffix - a through-hole, 0.6-inch wide package compliant with JEDEC MS-001. It is pin-compatible with other members of the SN74ACT72xxL family in NP packaging and supports breadboard prototyping and legacy PCB assembly.