Texas Instruments SN74ABT16640DL

Overview

SN74ABT16640DL from Texas Instruments is an inverting 16-bit bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between A and B buses in industrial and embedded systems. It supports dual 8-bit or single 16-bit operation, features –32-mA high-drive IOH and 64-mA IOL, operates from 4.5 V to 5.5 V, and is rated for –40°C to 85°C.

For engineers reviewing the SN74ABT16640DL datasheet, SN74ABT16640DL pinout, SN74ABT16640DL application, or SN74ABT16640DL equivalent, key selection criteria include direction-control logic (1DIR/2DIR), output-enable timing (tPZH/tPLZ ≤ 5.5 ns), flow-through pinout for PCB layout optimization, and DL-package thermal impedance (94°C/W).

Technical Context

This device implements two independent 8-bit inverting transceiver sections, each with dedicated DIR and OE controls. Signal direction is determined by logic level on 1DIR/2DIR (L = B→A, H = A→B), while 1OE/2OE enable/disable all outputs simultaneously into high-impedance state.

It uses EPIC-II^B BiCMOS process for low power dissipation and high noise immunity, with distributed V_CC/GND pins minimizing switching noise. VOLP (output ground bounce) is <1 V at V_CC = 5 V, TA = 25°C, and latch-up performance exceeds 500 mA per JESD-17.

Key Specifications

Pinout & Package

SN74ABT16640DL is housed in a 48-pin Shrink Small-Outline Package (SSOP-DL), 300-mil body width, with 0.5-mm lead pitch and 1.2-mm max height. Pin 1 identifier located at top-left corner of package marking area.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ABT16245DL, SN74ABT16640DL provides inverting logic essential for certain bus arbitration schemes, while SN74LVC16245ADGGR offers lower voltage operation but sacrifices 5-V compatibility and drive capability-making SN74ABT16640DL optimal for legacy 5-V industrial backplanes requiring robust noise immunity and high current drive.

Availability

SN74ABT16640DL is available at Aetrix Electronics and suitable for industrial backplane interfaces, modular PLC I/O expansion, legacy system bus bridges, and test equipment data acquisition interfaces requiring stable component supply across extended product lifecycles.

Supply support for SN74ABT16640DL 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 for industrial, automotive, and communications markets.

The ABT logic family-including SN74ABT16640DL-is engineered for high-speed, low-noise 5-V bus interfacing in mission-critical industrial control and instrumentation systems.

FAQ

What is the function of the 1DIR and 2DIR pins on the SN74ABT16640DL?

The 1DIR and 2DIR pins on the SN74ABT16640DL are direction-control inputs for the two independent 8-bit transceiver sections. When 1DIR is LOW, data flows from the B bus to the A bus (1B→1A); when HIGH, data flows from A to B (1A→1B). The same logic applies to 2DIR and the second section. This enables flexible bidirectional communication without external logic, and is fundamental to the SN74ABT16640DL's role in bus arbitration and modular I/O systems.

Does the SN74ABT16640DL support hot-swap or live-insertion scenarios?

Yes-the SN74ABT16640DL supports controlled hot-swap operation when OE inputs are tied to V_CC via appropriate pullup resistors, ensuring outputs remain in high-impedance state during power sequencing. Its latch-up immunity (>500 mA per JESD-17) and input clamp current (–18 mA) protect against transients during insertion. However, full hot-swap compliance requires external circuitry (e.g., slew-rate limiting, current limiting) beyond the SN74ABT16640DL's native capabilities.

Can the SN74ABT16640DL be used with 3.3-V logic levels?

No-the SN74ABT16640DL is specified only for 4.5 V to 5.5 V supply operation and has TTL-compatible input thresholds (V_IL = 0.8 V, V_IH = 2.0 V). Driving its inputs directly from 3.3-V logic may result in marginal or unreliable switching. For 3.3-V systems, consider SN74LVC16245ADGGR instead. The SN74ABT16640DL must be used in strictly 5-V domains or with level-shifting circuitry.

What is the significance of the "flow-through architecture" mentioned in the SN74ABT16640DL datasheet?

The flow-through architecture of the SN74ABT16640DL refers to its optimized pin arrangement: A-bus signals (1A1–1A8, 2A1–2A8) are placed on one side of the DL package, while corresponding B-bus signals (1B1–1B8, 2B1–2B8) are on the opposite side. This eliminates trace crossovers on PCBs, reduces layer count, improves signal integrity, and simplifies layout-especially critical in high-density industrial backplanes where the SN74ABT16640DL is commonly deployed.

How does the SN74ABT16640DL handle power-up and power-down sequencing?

The SN74ABT16640DL requires OE inputs to be held HIGH (via pullup to V_CC) during power-up/down to guarantee high-impedance outputs and prevent bus contention. Its internal design does not inherently guarantee safe state without external biasing. This behavior is explicitly documented in the datasheet and applies to all operating conditions of the SN74ABT16640DL-failure to implement proper OE pullup may cause data corruption or damage to connected devices during power transitions.