Texas Instruments SN74ACT7882-15PN

Overview

SN74ACT7882-15PN from Texas Instruments is a clocked 2048 × 18-bit asynchronous FIFO memory IC with independent read/write clocks, 11 ns access time, programmable almost-full/almost-empty flag (AF/AE), and 80-pin LQFP (PN) package. It enables data rate bridging between mismatched clock domains in high-speed digital systems such as network packet buffers and video frame synchronizers.

For engineers reviewing the SN74ACT7882-15PN datasheet, SN74ACT7882-15PN pinout, SN74ACT7882-15PN application, or SN74ACT7882-15PN equivalent, key selection considerations include its dual-clock synchronization capability, 67 MHz maximum clock frequency, 18-bit parallel I/O width, and support for cascading in word depth or width without external logic.

Technical Context

The SN74ACT7882-15PN implements a synchronous write control path driven by WRTCLK and asynchronous read path synchronized to RDCLK, enabling true clock domain crossing. Its internal 2048 × 18 RAM array supports concurrent read and write operations with status flags (IR, OR, HF, AF/AE) generated synchronously to their respective clocks.

Flag logic includes programmable AF/AE boundary via DAF input and D9–D0 during reset, defaulting to X = 256 words; half-full (HF) asserts at ≥1024 words; input-ready (IR) and output-ready (OR) provide handshake signaling with precise timing alignment to WRTCLK and RDCLK edges.

Key Specifications

Pinout & Package

SN74ACT7882-15PN uses an 80-pin Low-Profile Quad Flat Package (LQFP-PN) with exposed thermal pad, JEDEC MS-026 compliant, 12.2 mm × 12.2 mm body size, 0.5 mm lead pitch, and moisture sensitivity level (MSL) 3 (220°C peak reflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ACT7881-15PN and SN74ACT7811-15PN, the SN74ACT7882-15PN uniquely delivers programmable AF/AE offset and full 2048-word depth with half-full flag-critical for adaptive buffer management in high-reliability communication and imaging systems.

Availability

SN74ACT7882-15PN is available at Aetrix Electronics and suitable for network packet buffering, video frame synchronization, and industrial PLC data acquisition requiring stable component supply and long-term production continuity.

Supply support for SN74ACT7882-15PN 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 experience in high-reliability timing and interface ICs.

The SN74ACT7882-15PN belongs to TI's Widebus™ family of high-speed logic devices, designed specifically for clock-domain bridging and data buffering in telecommunications, industrial automation, and digital video systems.

FAQ

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

The SN74ACT7882-15PN supports a maximum clock frequency of 67 MHz for both WRTCLK and RDCLK inputs, verified under recommended operating conditions (VCC = 4.5 V to 5.5 V, TA = 0°C to 70°C). This rating applies to the -15 speed grade and is measured with CL = 50 pF load. The device maintains timing compliance across its full voltage and temperature range without derating.

How is the AF/AE flag programmed on the SN74ACT7882-15PN?

The AF/AE flag on the SN74ACT7882-15PN is programmed during reset by driving DAF low and presenting the desired 10-bit offset value (X) on D9–D0 before asserting RESET. When RESET goes high with DAF held low, the value is latched. If DAF remains high during reset, the default X = 256 is used. The SN74ACT7882-15PN retains the programmed value across power cycles until reprogrammed.

Can the SN74ACT7882-15PN be cascaded for greater memory depth or width?

Yes, the SN74ACT7882-15PN supports both word-depth and word-width expansion. For depth expansion (e.g., 4096 × 18), two devices are chained serially using OR→IR handshaking. For width expansion (e.g., 2048 × 36), control signals are shared and data buses concatenated. The SN74ACT7882-15PN's dedicated cascade pins and flag logic eliminate need for external glue logic in either configuration.

What are the key timing requirements for reliable read/write operation of the SN74ACT7882-15PN?

For reliable operation, the SN74ACT7882-15PN requires OE, RDEN1, and RDEN2 to be high ≥4 ns before RDCLK rising edge; WRTEN1/WRTEN2 must be high ≥4 ns before WRTCLK rising edge; and data D0–D17 must be stable ≥5 ns before WRTCLK rising edge. Hold times are zero for most signals, simplifying timing closure in synchronous designs using the SN74ACT7882-15PN.

Does the SN74ACT7882-15PN support 3.3-V logic interfaces?

No, the SN74ACT7882-15PN is a 5-V-only device with VIH(min) = 2.0 V and VIL(max) = 0.8 V, designed for TTL/ACT logic families. It does not support 3.3-V input thresholds or mixed-voltage operation. Interfacing with 3.3-V systems requires level-shifting circuitry or compatible 5-V tolerant controllers. The SN74ACT7882-15PN's absolute maximum ratings prohibit sustained operation below 4.5 V supply.