Texas Instruments SN74ABTR2245DW

Overview

SN74ABTR2245DW from Texas Instruments is an octal transceiver with 3-state outputs, designed for asynchronous bidirectional data bus communication between A and B ports. It features integrated 25-Ω series output resistors, operates from 4.5 V to 5.5 V, supports –40°C to 85°C temperature range, and uses SOIC-20 (DW) packaging. It enables isolated bus coupling in memory and peripheral interfacing applications.

For engineers reviewing the SN74ABTR2245DW datasheet, SN74ABTR2245DW pinout, SN74ABTR2245DW application, or SN74ABTR2245DW equivalent, key selection criteria include direction-control logic behavior, 3-state isolation timing (tPZH/tPHZ ≤ 6.3 ns), integrated series termination, high-impedance state during power-up/down, and compatibility with 5-V TTL/CMOS systems.

Technical Context

The SN74ABTR2245DW implements a dual-bus transceiver architecture with independent DIR (direction) and OE (output enable) control inputs. Its EPIC-II^B BiCMOS process delivers low power dissipation while maintaining TTL-compatible input thresholds (V_IL = 0.8 V, V_IH = 2 V) and drive strength (I_OL/I_OH = ±12 mA).

It guarantees high-impedance operation when V_CC is below 2.1 V, and requires external pull-up on OE above that threshold to ensure isolation. Output ground bounce (V_OLP) remains under 1 V at 5 V/25°C, and latch-up immunity exceeds 500 mA per JESD-17.

Key Specifications

Pinout & Package

SN74ABTR2245DW is housed in a 20-pin SOIC (DW) package with 1.27 mm pitch, 7.6 mm body width, and 2.65 mm max height. Pin 1 is located at the top-left corner with notch or index mark indication.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ABTR2245DW, SN74LVC2245APW offers voltage scalability but adds BOM and layout overhead, while SN74ABT2245N preserves full functional equivalence at the cost of thermal performance and modern assembly compatibility.

Availability

SN74ABTR2245DW is available at Aetrix Electronics and suitable for memory bus isolation, peripheral interface bridging, backplane data routing, and automated test equipment signal switching requiring stable component supply and long-term industrial availability.

Supply support for SN74ABTR2245DW 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 interface ICs.

The ABTR2245 family was engineered for robust 5-V bus interfacing in industrial computing and instrumentation, emphasizing noise immunity, power sequencing safety, and minimal external component count.

FAQ

What is the recommended operating voltage range for SN74ABTR2245DW?

The SN74ABTR2245DW is specified for continuous operation from 4.5 V to 5.5 V. Operation outside this range may cause undefined logic states or damage. The device enters a guaranteed high-impedance state when V_CC drops below 2.1 V, making it safe during brown-out conditions. Always maintain V_CC within the recommended range for reliable SN74ABTR2245DW functionality.

Does SN74ABTR2245DW require external series termination resistors?

No. The SN74ABTR2245DW integrates 25-Ω series resistors on all A- and B-port outputs, specifically designed to suppress transmission-line reflections on typical PCB traces. This eliminates the need for eight discrete 25-Ω resistors, simplifying layout and reducing BOM cost. External termination is unnecessary unless driving unusually long or impedance-mismatched lines beyond the device's design intent.

How does the DIR and OE pin interaction affect SN74ABTR2245DW bus behavior?

When OE is high, both A and B ports are in high-impedance regardless of DIR state - fully isolating the buses. When OE is low, DIR determines direction: low enables B→A data flow; high enables A→B flow. This two-level control allows precise bus arbitration and prevents contention. The SN74ABTR2245DW function table explicitly defines these states, and violating them risks undefined output behavior.

What is the thermal resistance (θ_JA) of the SN74ABTR2245DW package?

The SOIC-20 (DW) package of the SN74ABTR2245DW has a junction-to-ambient thermal resistance (θ_JA) of 97°C/W under standard JEDEC test conditions. This value assumes a 1-inch² copper pad with two vias. Actual thermal performance depends on PCB layout; adding thermal relief or ground-plane connections can improve heat dissipation. For sustained operation near maximum ICC, verify board-level temperature rise using this θ_JA value.

Is SN74ABTR2245DW compatible with 3.3-V logic inputs?

Yes - the SN74ABTR2245DW accepts 3.3-V logic levels on DIR and OE inputs, as its V_IH is 2.0 V (min) and V_IL is 0.8 V (max) at V_CC = 5 V. However, A- and B-port I/O remain 5-V tolerant and drive 5-V signals; interfacing with 3.3-V devices requires external level-shifting or clamping to avoid overvoltage damage. The SN74ABTR2245DW itself does not perform voltage translation.