Texas Instruments SN74ABT7819A-12PN

Overview

SN74ABT7819A-12PN from Texas Instruments is a clocked bidirectional FIFO memory IC with dual 512 × 18 × 2 SRAM architecture, supporting independent asynchronous CLKA/CLKB clocks up to 80 MHz, 9 ns access time at 50-pF load, and programmable almost-full/almost-empty flags. It serves as a high-speed data bridge between mismatched microprocessor buses in telecom line cards and packet-switching interfaces.

For engineers reviewing the SN74ABT7819A-12PN datasheet, SN74ABT7819A-12PN pinout, SN74ABT7819A-12PN application, or SN74ABT7819A-12PN equivalent, key selection criteria include its dual-port timing independence, 18-bit bidirectional data width per port, PH/PN-package compatibility, and programmable flag offsets for precise buffer management in real-time data pipelines.

Technical Context

The SN74ABT7819A-12PN implements two independent 512-word × 18-bit synchronous FIFOs (FIFOA–B and FIFOB–A), each with fully separate clock domains (CLKA and CLKB), enabling true bidirectional data flow without shared timing constraints. Its control logic uses edge-triggered enable signals (WENA/RENA/WENB/RENB) synchronized to respective clock rising edges.

Flag generation is two-stage synchronized: IRA/ORA are clocked by CLKA; IRB/ORB by CLKB; AF/AEA/HFA derive from FIFOA–B status; AF/AEB/HFB from FIFOB–A. Programmable AF/AE offsets (X/Y) are latched via PENA/PENB on CLKA/CLKB rising edges after reset, using A0–A7/B0–B7 as offset registers.

Key Specifications

Pinout & Package

SN74ABT7819A-12PN is housed in an 80-pin Thin Plastic Quad Flatpack (PN) package, measuring 20 mm × 14 mm × 2.4 mm (JEDEC MO-152), with 0.65-mm lead pitch and exposed thermal pad for enhanced heat dissipation (θJA = 62°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ABT7819A-12PN, IDT72V2115L10PFI offers higher density and industrial temperature range but mandates voltage translation, while NB3N502MNR2G simplifies clocking with an on-chip PLL yet sacrifices true dual-clock autonomy-making SN74ABT7819A-12PN optimal for mixed-voltage, high-speed, asynchronous interconnects.

Availability

SN74ABT7819A-12PN is available at Aetrix Electronics and suitable for telecom line cards, PCI-to-processor bridges, and real-time video synchronization systems requiring stable component supply, long-term obsolescence planning, and traceable sourcing.

Supply support for SN74ABT7819A-12PN 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, with decades of expertise in high-speed interface ICs and industrial-grade reliability.

The SN74ABT7819A-12PN belongs to TI's Widebus™ family of advanced logic devices, engineered specifically for high-bandwidth, low-latency data buffering in telecommunications, computing, and industrial automation systems.

FAQ

What is the maximum supported clock frequency for SN74ABT7819A-12PN?

The SN74ABT7819A-12PN supports a maximum clock frequency of 80 MHz, as specified for the -12 speed grade. This corresponds to a minimum clock period of 12.5 ns and enables reliable operation with setup/hold margins across the full commercial temperature range (0°C to 70°C). The device achieves this performance using advanced BiCMOS technology and optimized internal timing paths.

How does the programmable almost-full/almost-empty flag work on SN74ABT7819A-12PN?

The SN74ABT7819A-12PN implements two independent programmable flags-AF/AEA for FIFOA–B and AF/AEB for FIFOB–A-each configurable with separate almost-empty (X) and almost-full (Y) offsets (0–255). After reset, asserting PENA or PENB latches A0–A7 or B0–B7 as the offset value on the next CLKA or CLKB rising edge. The flag goes high when FIFO depth ≤ X or ≥ (512 − Y), enabling precise buffer-level handshaking.

Can SN74ABT7819A-12PN operate with asynchronous CLKA and CLKB clocks?

Yes, SN74ABT7819A-12PN explicitly supports asynchronous operation of CLKA and CLKB. Its dual-port architecture isolates timing domains: IRA/ORA are synchronized to CLKA, while IRB/ORB are synchronized to CLKB. This eliminates metastability risks and enables robust data transfer between systems with unrelated clock sources-such as a 66-MHz CPU bus and a 80-MHz network interface-without external synchronizers.

What package type is used for SN74ABT7819A-12PN?

SN74ABT7819A-12PN uses an 80-pin Thin Plastic Quad Flatpack (PN) package per JEDEC MO-152, with dimensions of 20 mm × 14 mm × 2.4 mm and 0.65-mm lead pitch. It features an exposed thermal pad for improved heat dissipation (θJA = 62°C/W) and 8 VCC + 12 GND pins to minimize power-supply noise in high-speed applications.

Does SN74ABT7819A-12PN support reset functionality for individual FIFOs?

Yes, SN74ABT7819A-12PN provides independent asynchronous reset for each FIFO: RSTA resets FIFOA–B (setting IRA low, ORB low, HFA low, AF/AEA high), while RSTB resets FIFOB–A (setting IRB low, ORA low, HFB low, AF/AEB high). Each reset requires four low-to-high transitions of both CLKA and CLKB while the respective reset pin is held low, ensuring deterministic pointer and flag initialization.