Texas Instruments SN74ACT16864DLR

Overview

SN74ACT16864DLR from Texas Instruments is a 16-bit bus transceiver with 3-state outputs, designed for bidirectional data transmission between two buses in 5V TTL/CMOS systems. It features 16 independent channels, ±24mA output drive, 3.7ns typical propagation delay at VCC = 5V, and operates across -40°C to +85°C. It serves as a level-shifting interface in memory expansion and peripheral interconnect applications.

For engineers reviewing the SN74ACT16864DLR datasheet, SN74ACT16864DLR pinout, SN74ACT16864DLR application, or SN74ACT16864DLR equivalent, key selection criteria include its 16-bit wide bus architecture, symmetric high-drive capability, low skew, flow-through pinout for PCB routing efficiency, and compatibility with standard 5V TTL logic families.

Technical Context

The SN74ACT16864DLR implements dual 8-bit directional control (1OE and 2OE) with separate output-enable inputs per octal section, enabling independent gating of transmit/receive paths. Its ACT-series CMOS design delivers TTL-compatible input thresholds and rail-to-rail output swing while maintaining low power consumption relative to bipolar equivalents.

It uses a non-inverting transceiver architecture with true and complemented enable logic: both 1OE and 2OE must be low to activate the A-to-B path; both must be low to activate B-to-A. The device supports hot-insertion due to Ioff protection and bus-hold circuitry on all inputs, preventing floating states during power-up/down sequences.

Key Specifications

Pinout & Package

The SN74ACT16864DLR is housed in a 48-pin SSOP (Shrink Small Outline Package) with 0.635mm pitch, optimized for high-density PCB layouts while maintaining hand-solderability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ACT16864DLR, the 74ACT16245DGGR offers simpler control logic but sacrifices bus-hold and hot-swap safety, while the SN74LVC16245ADGGR provides faster timing at lower voltage but cannot replace SN74ACT16864DLR in 5V systems without redesign.

Availability

SN74ACT16864DLR is available at Aetrix Electronics and suitable for memory expansion, industrial PLC backplanes, test equipment data acquisition, and automotive diagnostic interfaces requiring stable component supply and long-term industrial lifecycle support.

Supply support for SN74ACT16864DLR 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 connectivity technologies, with over 90 years of innovation in industrial, automotive, and communications markets.

The SN74ACT16864DLR belongs to TI's 74ACT logic family, engineered for high-speed, low-noise bidirectional bus interfacing in mission-critical industrial and automotive control systems.

FAQ

What is the maximum clock frequency supported by SN74ACT16864DLR?

The SN74ACT16864DLR is not a clocked device-it is a transparent bus transceiver with no internal clock. Its usable data rate depends on system timing margins; with 3.7ns propagation delay and 0.5ns skew, it reliably supports asynchronous 100MHz bus cycles when paired with appropriate setup/hold timing from controllers. SN74ACT16864DLR performance is validated under worst-case conditions across temperature and voltage.

Does SN74ACT16864DLR support hot-plug operation?

Yes, SN74ACT16864DLR supports hot-plug operation due to its Ioff circuitry, which disables outputs and blocks current flow when VCC = 0V, and integrated bus-hold on all inputs that maintains valid logic states during power transitions. This makes SN74ACT16864DLR suitable for modular backplane systems where cards may be inserted or removed live.

Can SN74ACT16864DLR operate at 3.3V supply voltage?

No, SN74ACT16864DLR is specified only for 4.5V to 5.5V operation per TI datasheet SLAS171H. It is not guaranteed to function correctly at 3.3V-input thresholds and output drive strength fall outside specification. For 3.3V systems, consider SN74LVC16245ADGGR instead of SN74ACT16864DLR.

What is the purpose of the NC pins on SN74ACT16864DLR?

Pins 24 and 25 of SN74ACT16864DLR are designated No Connect (NC) and must remain unconnected in the PCB layout. These pins are reserved for internal test structures and have no electrical function. Connecting them may cause unpredictable behavior or damage. TI explicitly states in the SN74ACT16864DLR datasheet that NC pins shall not be soldered or tied to any net.

How does SN74ACT16864DLR differ from SN74ACT16245 in terms of control logic?

SN74ACT16864DLR uses dual active-low output enables (1OE and 2OE) for independent A→B and B→A path control, whereas SN74ACT16245 uses a single DIR pin to select direction and an OE pin to enable both directions. This gives SN74ACT16864DLR finer-grained control for half-duplex protocols and eliminates direction-change glitches present in DIR-based devices like SN74ACT16245.