Texas Instruments SN74ACT7882-15FN

Overview

SN74ACT7882-15FN from Texas Instruments is a clocked 2048 × 18-bit first-in, first-out (FIFO) memory IC with independent asynchronous read/write ports, 11 ns access time at 50-pF load, and programmable almost-full/almost-empty flag logic. It operates from 0°C to 70°C with 4.5–5.5 V supply and supports depth/width cascading for system-level buffering in high-speed data acquisition and protocol bridging.

For engineers reviewing the SN74ACT7882-15FN datasheet, SN74ACT7882-15FN pinout, SN74ACT7882-15FN application, or SN74ACT7882-15FN equivalent, key selection criteria include its 67 MHz maximum clock frequency, dual-clock synchronization capability, 68-pin PLCC (FN) package with verified pin mapping, and support for IR/OR status flag handshaking in burst-mode interfaces.

Technical Context

The SN74ACT7882-15FN implements a synchronous FIFO architecture with separate write and read pointer control logic, enabling independent clock domains for WRTCLK and RDCLK. Its status-flag generation (AF/AE, HF, IR, OR) is fully synchronized to respective clocks, and the AF/AE offset is programmable via DAF-triggered capture of D9–D0 during reset.

It features ACT-series TTL-compatible inputs and outputs with ±8 mA/16 mA drive strength, 5-V operation, and noninverting data path. The device supports cascading in both word width (parallel expansion) and word depth (serial chaining), with no external glue logic required for multi-device configurations.

Key Specifications

Pinout & Package

SN74ACT7882-15FN uses a 68-pin plastic leaded chip carrier (PLCC) package (FN), JEDEC MS-018 compliant, with 0.050-inch pitch and gull-wing J-leads. Thermal resistance θ_JA = 39°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ACT7881-15FN and SN74ACT7811-15FN, the SN74ACT7882-15FN delivers double the depth of the former and adds programmable flow control absent in the latter - making it optimal for applications requiring both extended buffering and adaptive handshaking.

Availability

SN74ACT7882-15FN is available at Aetrix Electronics and suitable for high-speed data acquisition, protocol bridging, and industrial control backplane applications requiring stable component supply and long-term obsolescence management.

Supply support for SN74ACT7882-15FN 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 heritage in high-reliability industrial and automotive components.

The SN74ACT7882-15FN belongs to TI's Widebus™ family of high-speed interface ICs, designed specifically for robust, low-latency data buffering in mixed-clock-domain systems across test equipment, communications infrastructure, and factory automation.

FAQ

What is the maximum operating frequency of the SN74ACT7882-15FN?

The SN74ACT7882-15FN supports a maximum clock frequency of 67 MHz for both WRTCLK and RDCLK inputs, as specified in the 'ACT7882-15 speed grade. This allows sustained 67 million words per second throughput under recommended operating conditions (VCC = 4.5–5.5 V, TA = 0°C to 70°C), with timing validated at CL = 50 pF.

How is the almost-full/almost-empty flag programmed on the SN74ACT7882-15FN?

The AF/AE flag on the SN74ACT7882-15FN is programmed by asserting DAF low to capture D9–D0 as the offset value X during RESET. With DAF held low, a RESET pulse defines AF/AE using that X; holding DAF high selects the default X = 256. This occurs only during reset cycles and does not affect normal operation of the SN74ACT7882-15FN.

Does the SN74ACT7882-15FN support cascading for increased memory depth or width?

Yes, the SN74ACT7882-15FN supports both word-depth and word-width expansion. Depth expansion chains devices serially using OR→IR handshaking; width expansion parallels devices with shared control signals and composite status flags. The SN74ACT7882-15FN datasheet confirms this capability with reference schematics for 4096 × 18 and 2048 × 36 configurations.

What package type and pin count does the SN74ACT7882-15FN use?

The SN74ACT7882-15FN uses a 68-pin plastic leaded chip carrier (PLCC) package designated FN, compliant with JEDEC MS-018. Its top-view pinout is fully documented in the SCAS445C datasheet, including dedicated VCC/GND pairs, 18-bit data I/O banks, and synchronized status flag outputs - all verified for this exact orderable part.

What are the key timing parameters for read and write operations on the SN74ACT7882-15FN?

For the SN74ACT7882-15FN, key timing parameters include: t_su(WRTEN) = 4 ns before WRTCLK↑, t_su(OE/RDEN) = 4 ns before RDCLK↑, t_pd(RDCLK→Q) = 3–12 ns, and t_pd(WRTCLK→AF/AE) = 6–17 ns. All values are guaranteed for the -15 speed grade at VCC = 4.5 V, CL = 50 pF, and TA = 0°C to 70°C - critical for synchronizing the SN74ACT7882-15FN in tight-tolerance designs.