Texas Instruments SN74ABT245BDWRG4

Overview

SN74ABT245BDWRG4 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 control and embedded computing systems. It supports hot insertion via I_off and power-up 3-state logic, delivers ±32-mA high-drive outputs (I_OH/I_OL), operates from 4.5 V to 5.5 V, and features low ground bounce (<1 V at V_CC = 5 V, T_A = 25°C).

For engineers reviewing the SN74ABT245BDWRG4 datasheet, SN74ABT245BDWRG4 pinout, SN74ABT245BDWRG4 application, or SN74ABT245BDWRG4 equivalent, this page provides verified functional specifications, SOIC-20 package terminal mapping, hot-swap design guidance, and validated alternative options for bus isolation and level-shifting use cases.

Technical Context

This device implements dual-directional 8-bit data flow controlled by DIR (direction) and OE (output enable) inputs, enabling either A→B or B→A transmission while maintaining bus isolation when OE is high. Its TTL-compatible input thresholds (V_IL = 0.8 V, V_VIH = 2 V) and robust output drive ensure interoperability with legacy 5-V logic families.

The SN74ABT245BDWRG4 integrates I_off circuitry that disables outputs during power-down to prevent backflow current, and power-up 3-state logic that holds outputs high-impedance until V_CC stabilizes - both critical for live-insertion systems. Latch-up immunity exceeds 500 mA per JESD 17, and ESD protection meets 2000-V HBM and 200-V MM standards.

Key Specifications

Pinout & Package

SN74ABT245BDWRG4 is housed in a 20-pin SOIC (DW) package with 0.65-mm lead pitch and 1.75-mm maximum height. The body dimensions are 7.5 mm × 12.8 mm, and the exposed pad is not present (standard plastic SOIC).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245A and SN74ABT245BN, the SN74ABT245BDWRG4 uniquely combines 5-V TTL compatibility, hot-swap safety, and SOIC-20 surface-mount packaging - making it optimal for volume-manufactured industrial controllers requiring drop-in reliability and legacy bus interoperability.

Availability

SN74ABT245BDWRG4 is available at Aetrix Electronics and suitable for industrial PLC backplanes, automated test equipment channel switching, and embedded data acquisition front-ends requiring stable component supply across extended product lifecycles.

Supply support for SN74ABT245BDWRG4 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 and automotive electronics.

The SN74ABT245BDWRG4 belongs to TI's ABT logic family, engineered for high-speed, high-drive 5-V bus interfacing in harsh industrial environments where reliability, hot-swap capability, and noise immunity are critical.

FAQ

What is the recommended power-up sequence for SN74ABT245BDWRG4 to avoid bus contention?

TI specifies tying OE to V_CC via a pullup resistor (minimum value determined by driver sink capability) to ensure outputs remain in high-impedance state during power ramp-up. This prevents unintended data flow or bus conflicts before system initialization completes. The SN74ABT245BDWRG4's built-in power-up 3-state logic activates automatically once V_CC reaches ~2.1 V, making external sequencing unnecessary.

Can SN74ABT245BDWRG4 interface directly with 3.3-V logic devices?

No - SN74ABT245BDWRG4 is a 5-V-only device with TTL-compatible input thresholds (V_IL = 0.8 V, V_VIH = 2 V). While its outputs swing rail-to-rail (0 V to 5 V), connecting them directly to 3.3-V inputs risks overvoltage damage. A level-shifter such as TXS0108E or discrete resistor divider is required for safe 3.3-V interface. The SN74ABT245BDWRG4 itself does not support mixed-voltage operation.

What is the thermal resistance (θ_JA) of SN74ABT245BDWRG4 in its SOIC-20 package?

The SOIC-20 (DW) package used by SN74ABT245BDWRG4 has a specified junction-to-ambient thermal resistance (θ_JA) of 58°C/W under JEDEC-standard conditions (2-layer board, 1-in² copper). This value assumes no additional thermal vias or heatsinking. For continuous 64-mA output loading on all eight channels, junction temperature rise remains within safe limits (<85°C ambient + 58°C/W × 0.5 W ≈ 114°C) - well below the 150°C absolute max rating.

How does the I_off feature protect the SN74ABT245BDWRG4 during hot insertion?

The I_off circuitry in SN74ABT245BDWRG4 actively disables all outputs when V_CC = 0 V, limiting leakage current to ±100 µA even if A or B bus voltages reach 5.5 V. This prevents reverse current flow from powered buses into the unpowered IC, avoiding latch-up, overheating, or corruption of adjacent devices - a key requirement for hot-pluggable backplanes and modular I/O systems.

Is SN74ABT245BDWRG4 pin-compatible with other members of the SN74ABT245B family?

Yes - all SN74ABT245B variants (including SN74ABT245BDWRG4, SN74ABT245BDBR, SN74ABT245BPWR, etc.) share identical pinouts across SOIC, SSOP, TSSOP, TVSOP, and VQFN packages. The DIR, OE, A1–A8, B1–B8, V_CC, and GND assignments are standardized per the datasheet top-view diagrams. This allows direct PCB footprint reuse when migrating between packages for cost, density, or thermal optimization.