Texas Instruments SN74ACT72211L20RJR

Overview

SN74ACT72211L20RJR from Texas Instruments is a 512 × 9-bit synchronous dual-clock FIFO memory IC with CMOS dual-port SRAM architecture, 15 ns write/read cycle time, TTL-compatible inputs, and programmable almost-empty/almost-full flags (default offsets: empty+7 / full−7). It operates from 0°C to 70°C and is used in asynchronous data bridging between mismatched bus domains.

For engineers reviewing the SN74ACT72211L20RJR datasheet, SN74ACT72211L20RJR pinout, SN74ACT72211L20RJR application, or SN74ACT72211L20RJR equivalent, key selection criteria include its 32-pin RJ package, synchronous read/write control with independent clocks, flag synchronization logic, 9-bit data path with parity support, and compatibility with IDT72211 family designs.

Technical Context

This FIFO implements first-in, first-out buffering using internal write and read address counters synchronized to WCLK and RCLK respectively. Its dual-port SRAM core supports independent, asynchronous or coincident clocking - enabling rate-matching between source and sink subsystems without shared timing constraints.

Flag generation uses flip-flop-synchronized outputs: EF and PAE are edge-triggered on RCLK; FF and PAF on WCLK. Programmable offset registers (8-bit LSB/MSB per flag) allow custom threshold configuration via WEN2/LD-controlled write sequences, with default values loaded at reset.

Key Specifications

Pinout & Package

SN74ACT72211L20RJR is housed in a 32-pin plastic J-leaded chip carrier (RJ) package with standard top-view pin numbering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT72211L15JI and SN74ACT72211L25RJR, SN74ACT72211L20RJR delivers optimal balance of speed (66.7 MHz), commercial-temperature compliance, and plastic-package cost efficiency - making it ideal for volume graphics and comms applications where 15 ns timing is required but extended temp or ceramic packaging is not.

Availability

SN74ACT72211L20RJR is available at Aetrix Electronics and suitable for graphics data buffering, high-speed communication queuing, and industrial bus protocol translation requiring stable component supply and long-term production continuity.

Supply support for SN74ACT72211L20RJR 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 SN74ACT72211L20RJR belongs to TI's ACT-family advanced CMOS FIFO product line, engineered specifically for high-reliability, low-latency data channeling between asynchronous subsystems in graphics, telecom, and test equipment.

FAQ

What is the memory organization of the SN74ACT72211L20RJR?

The SN74ACT72211L20RJR features a 512 × 9-bit synchronous FIFO memory structure, providing 4,608 bits of dual-port SRAM storage. This configuration supports 9-bit-wide data paths - commonly used for 8-bit data plus parity or packet header information - and is implemented with fully synchronous read and write ports controlled by independent clocks.

How does the SN74ACT72211L20RJR handle clock domain crossing between write and read operations?

The SN74ACT72211L20RJR handles clock domain crossing using separate, independently controlled WCLK and RCLK inputs with flip-flop-synchronized status flags: EF and PAE are synchronized to RCLK, while FF and PAF are synchronized to WCLK. This architecture prevents metastability and ensures reliable boundary detection without requiring external synchronizers or handshaking logic.

Can the programmable almost-empty and almost-full flags of the SN74ACT72211L20RJR be customized, and how?

Yes, the SN74ACT72211L20RJR supports customization of PAE and PAF thresholds via four 8-bit offset registers (empty LSB/MSB, full LSB/MSB). When WEN2/LD is held low during reset, the terminal becomes a load enable; subsequent WCLK edges write data to these registers in sequence. Default offsets are empty+7 and full−7, but user-defined values allow precise flow-control tuning for specific application latency requirements.

What package type and pin count does the SN74ACT72211L20RJR use?

The SN74ACT72211L20RJR is packaged in a 32-pin plastic J-leaded chip carrier (RJ) with standard top-view pinout. This surface-mount package provides mechanical robustness and thermal performance suitable for commercial-grade applications, and its pin layout matches industry-standard FIFO footprint conventions for drop-in compatibility in existing designs.

Is the SN74ACT72211L20RJR compatible with IDT72211-series FIFOs?

Yes, the SN74ACT72211L20RJR is fully compatible with the IDT72211/72221/72231/72241 family in terms of pinout, functional behavior, timing specifications, and flag logic. This compatibility enables direct substitution in legacy IDT-based designs without PCB or firmware changes, preserving system-level timing margins and interface protocols.