Texas Instruments 74ACT16651DL

Overview

74ACT16651DL from Texas Instruments is a 16-bit bus transceiver with dual 8-bit registers, 3-state outputs, inverting data paths, and independent A/B bus control logic. It operates at 5 V, supports up to 90 MHz clock frequency, delivers ±24 mA output drive, and is specified for –40°C to 85°C industrial temperature range. It enables real-time or stored-data bidirectional transfer between two 16-bit buses in high-speed digital systems.

For engineers reviewing the 74ACT16651DL datasheet, 74ACT16651DL pinout, 74ACT16651DL application, or 74ACT16651DL equivalent, key selection criteria include its multiplexed flow-through architecture, simultaneous real-time/stored-data routing capability, distributed V_CC/GND pinning for noise reduction, and compatibility with TTL-level inputs in 56-pin SSOP (DL) packaging.

Technical Context

The 74ACT16651DL integrates two independent 8-bit D-type flip-flop register banks-one per bus-with separate clock (CLKAB/CLKBA), select (SAB/SBA), and output-enable (OEAB/OEBA) controls. Its flow-through architecture allows concurrent real-time pass-through and registered data storage without decoding glitches during mode transitions.

It uses TI's EPIC™ 1-µm CMOS process, features distributed power/ground pins to minimize switching noise, and provides latch-up immunity of 500 mA at 125°C. The device supports both isolated bus operation and synchronized dual-bus data capture, with input voltage tolerance up to V_CC + 0.5 V and 50 pF typical load capacitance per transceiver.

Key Specifications

Pinout & Package

74ACT16651DL is housed in a 56-pin Shrink Small-Outline Package (SSOP-DL), 300-mil body width, with 0.025-inch (0.635 mm) pin pitch and gull-wing leads. The package features distributed V_CC and GND pins across the perimeter to suppress simultaneous switching noise.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit registered transceiver applications.

Compared with 74ACT16651DL, 74ACT16245DL omits register functionality and select control, reducing complexity but eliminating stored-data routing. SN74LVTH16651DL retains identical pinout and logic function but shifts to 3.3 V operation and lower dynamic power - making it suitable for voltage-scaled upgrades rather than direct 5 V replacements.

Availability

74ACT16651DL is available at Aetrix Electronics and suitable for industrial automation, embedded computing, and test instrumentation applications requiring stable component supply, long-term lifecycle support, and verified 5 V logic compatibility.

Supply support for 74ACT16651DL 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 over 50 years of innovation in high-reliability logic families.

The 74ACT16651DL belongs to TI's Widebus™ family of advanced bus-interface ICs, designed specifically for high-speed, noise-immune parallel bus management in industrial and computing systems.

FAQ

What is the maximum clock frequency supported by the 74ACT16651DL?

The 74ACT16651DL supports a maximum clock frequency of 90 MHz across its full industrial temperature range (–40°C to +85°C), as validated in the official Texas Instruments SCAS449A datasheet. This rating applies to both CLKAB and CLKBA inputs under recommended operating conditions (V_CC = 4.5 V to 5.5 V). The device achieves this speed using TI's EPIC™ 1-µm CMOS process and distributed power/ground architecture to maintain timing integrity.

Does the 74ACT16651DL support true bidirectional data flow without external direction control?

Yes, the 74ACT16651DL supports true bidirectional data flow on all A and B port pins without requiring external direction signals. Its architecture uses complementary output-enable inputs (OEAB/OEBA) and independent select-control inputs (SAB/SBA) to manage data direction and source (real-time vs. stored) internally. Each 8-bit segment operates autonomously, allowing simultaneous A→B and B→A transfers when configured appropriately - a core feature of the Widebus™ design.

What package type and pin count does the 74ACT16651DL use?

The 74ACT16651DL uses a 56-pin Shrink Small-Outline Package (SSOP), designated DL by Texas Instruments, with 300-mil body width and 0.025-inch pin pitch. This package provides twice the I/O density of standard SOIC while maintaining compatibility with automated SMT assembly. Pin assignments include four dedicated clock inputs, four select controls, four output enables, 32 bidirectional data lines (A1–A16, B1–B16), and ten power/ground terminals (four V_CC, six GND).

Can the 74ACT16651DL operate with TTL-level input signals?

Yes, the 74ACT16651DL features TTL-voltage compatible inputs, with guaranteed recognition of V_IL ≤ 0.8 V (low) and V_IH ≥ 2.0 V (high) across its full operating range. This allows direct interfacing with legacy 74LS, 74ALS, and microcontroller GPIOs without level-shifting circuitry. Input voltage tolerance extends to –0.5 V to V_CC + 0.5 V, supporting robust noise margin in electrically noisy industrial environments.

How does the 74ACT16651DL prevent glitches during real-time to stored-data transitions?

The 74ACT16651DL eliminates transition glitches through dedicated select-control circuitry (SAB/SBA) that decouples multiplexer switching from clock edges. When SAB or SBA changes state, internal logic ensures the output remains valid throughout the transition - unlike conventional mux-based implementations where race conditions cause momentary invalid states. This behavior is explicitly confirmed in the FUNCTION TABLE and Figure 1 of the SCAS449A datasheet, and enables deterministic bus arbitration in real-time control systems.