Texas Instruments SN74ABTH245PWR

Overview

SN74ABTH245PWR from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between A and B buses in industrial and embedded systems. It features ±32-mA high-drive outputs, bus-hold circuitry eliminating external pull resistors, Ioff support for hot insertion, and operates over –40°C to 85°C at 4.5–5.5 V supply. Used in backplane interface, memory expansion, and system-level bus isolation.

For engineers reviewing the SN74ABTH245PWR datasheet, SN74ABTH245PWR pinout, SN74ABTH245PWR application, or SN74ABTH245PWR equivalent, key selection criteria include direction-control logic behavior, 3-state enable timing (tPZH/tPLZ ≤ 6.2 ns), thermal performance in TSSOP-20 (θJA = 83°C/W), and compatibility with 5-V TTL/CMOS logic families.

Technical Context

This device implements a dual-directional 8-bit bus interface using EPIC-II^B BiCMOS technology to achieve low power dissipation while maintaining high drive strength. Its DIR input selects data flow direction (A→B or B→A), and OE enables/disables all outputs simultaneously into high-impedance state.

The SN74ABTH245PWR integrates bus-hold circuitry on all A and B data inputs to maintain valid logic levels when floating, and includes Ioff protection that disables outputs during power-down to prevent current backflow. Power-up 3-state ensures outputs remain high-Z until VCC exceeds 2.1 V or OE is actively pulled high.

Key Specifications

Pinout & Package

TSSOP-20 (PW) package: 6.95 mm × 4.4 mm × 1.2 mm profile, 0.65 mm lead pitch, exposed pad not electrically connected, RoHS-compliant NiPdAu finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245APWR and 74ABT245PW, the SN74ABTH245PWR uniquely combines hot-insertion safety, bus-hold integration, and industrial temperature range in a single 5-V TSSOP-20 package-making it optimal for field-upgradable and mixed-signal embedded systems.

Availability

SN74ABTH245PWR is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, and FPGA-based prototyping requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74ABTH245PWR 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 solutions, with decades of heritage in logic and interface IC design.

The SN74ABTH245PWR belongs to TI's ABTH logic family, engineered for high-reliability 5-V bus interfacing in harsh environments-emphasizing hot-swap resilience, noise immunity, and thermal stability.

FAQ

What is the maximum data rate supported by SN74ABTH245PWR?

The SN74ABTH245PWR does not specify a maximum data rate in its datasheet, but its propagation delays (tPLH/tPHL ≤ 3.9 ns at 5 V) support reliable operation up to approximately 100 MHz in well-terminated, low-capacitance bus configurations. Actual achievable rate depends on load capacitance, trace length, and termination scheme - for 50-pF loads, SN74ABTH245PWR maintains signal integrity through 25-MHz synchronous transfers.

Does SN74ABTH245PWR require external pull-up resistors on its data lines?

No, SN74ABTH245PWR does not require external pull-up or pull-down resistors on A1–A8 or B1–B8 inputs because it integrates active bus-hold circuitry. Each data line maintains its last-valid logic state with ±100 µA hold current, eliminating floating inputs and reducing BOM cost and PCB space - a key advantage over standard 74-series transceivers.

Can SN74ABTH245PWR be used in hot-swap applications?

Yes, SN74ABTH245PWR is explicitly designed for hot-insertion use cases. Its Ioff circuitry limits current to ±100 µA when VCC = 0, preventing backflow damage, and its power-up 3-state ensures outputs remain high-impedance until VCC exceeds 2.1 V or OE is asserted - both features are validated per JESD17 latch-up standards.

What is the thermal resistance (θJA) of SN74ABTH245PWR in its TSSOP package?

The SN74ABTH245PWR in TSSOP-20 (PW) package has a junction-to-ambient thermal resistance (θJA) of 83°C/W, measured per JEDEC JESD51 standards. This value assumes standard 2-layer PCB layout with 1-in² copper pour under the exposed pad area; actual thermal performance improves with enhanced copper planes or thermal vias.

How does the DIR and OE pin interaction affect bus isolation in SN74ABTH245PWR?

In SN74ABTH245PWR, OE is dominant: when OE is high (disabled), all outputs go high-Z regardless of DIR state - fully isolating both A and B buses. When OE is low (enabled), DIR then controls direction (A↔B). This two-level control enables precise bus arbitration: OE manages coarse isolation, DIR handles fine-grained data flow - critical for multi-master systems.