Texas Instruments SN74ABTR2245DBRE4

Overview

SN74ABTR2245DBRE4 from Texas Instruments is an octal transceiver with 3-state outputs, designed for bidirectional asynchronous 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 provides 12 mA sink capability per I/O. It is used in memory interface and bus isolation applications requiring controlled signal integrity.

For engineers reviewing the SN74ABTR2245DBRE4 datasheet, SN74ABTR2245DBRE4 pinout, SN74ABTR2245DBRE4 application, or SN74ABTR2245DBRE4 equivalent, key selection criteria include direction-control logic behavior, 3-state enable timing (tPZH/tPZL ≤ 6.3 ns), high-impedance state during power-up/down, and compatibility with 5-V TTL/CMOS systems.

Technical Context

This BiCMOS transceiver implements dual 8-bit bidirectional data paths controlled by DIR (direction) and OE (output enable) inputs. Its EPIC-II^B architecture delivers low power dissipation while maintaining TTL-compatible voltage thresholds (VIH = 2 V, VIL = 0.8 V) and fast propagation delays (tPLH/tPHL ≤ 4.5 ns at 5 V).

The device ensures robust system-level reliability via built-in 25-Ω series termination on all A- and B-port outputs-eliminating external resistors-and guarantees high-impedance isolation during power transitions (VCC < 2.1 V), latch-up immunity (>500 mA), and ESD protection (>2000 V HBM).

Key Specifications

Pinout & Package

SN74ABTR2245DBRE4 is packaged in a 20-pin Shrink Small-Outline (DB) package, 7.5 mm × 4.4 mm body, 1.2 mm max height, 0.65 mm lead pitch, JEDEC MO-153 compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC2245APWRE4 and SN74ABT2245N, the SN74ABTR2245DBRE4 uniquely combines 5-V operation, integrated 25-Ω termination, and surface-mount DB package - making it optimal for industrial bus interfaces requiring zero-external-component signal conditioning and industrial temperature support.

Availability

SN74ABTR2245DBRE4 is available at Aetrix Electronics and suitable for memory bus isolation, industrial backplane interfacing, and legacy system bus extension requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for SN74ABTR2245DBRE4 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 over 90 years of innovation in industrial, automotive, and communications markets.

The ABTR-series octal transceivers were developed to address high-reliability 5-V bus interfacing needs in industrial control and computing systems, emphasizing robustness, signal integrity, and seamless integration into legacy and mixed-voltage architectures.

FAQ

What is the function of the DIR pin on the SN74ABTR2245DBRE4?

The DIR (direction) pin on the SN74ABTR2245DBRE4 controls data flow direction: when DIR is LOW, data transfers from B-port to A-port; when DIR is HIGH, data flows from A-port to B-port. This bidirectional control enables flexible bus arbitration in systems like memory controllers or backplane interfaces. The SN74ABTR2245DBRE4 uses TTL-compatible thresholds (VIH ≥ 2 V, VIL ≤ 0.8 V) for reliable logic-level interpretation.

Does the SN74ABTR2245DBRE4 require external series resistors on its I/O pins?

No, the SN74ABTR2245DBRE4 does not require external series resistors because each A- and B-port output incorporates an integrated 25-Ω series resistor. This design suppresses overshoot and undershoot on PCB traces up to ~10 cm in length, reducing component count and layout complexity. Verified in the datasheet's "Outputs Have Equivalent 25-Ω Series Resistors" feature statement and confirmed in the output schematic diagram.

What happens to the outputs of the SN74ABTR2245DBRE4 during power-up?

During power-up, the SN74ABTR2245DBRE4 automatically places all outputs in a high-impedance state when VCC is below 2.1 V - preventing bus contention before system initialization completes. Once VCC exceeds 2.1 V, OE must be actively driven HIGH to maintain isolation. This behavior is specified in the "High-Impedance State During Power Up and Power Down" feature and validated in the recommended operating conditions table.

What is the maximum data rate supported by the SN74ABTR2245DBRE4?

The SN74ABTR2245DBRE4 supports effective data rates up to ~100 MHz, derived from its worst-case propagation delay (tPLH/tPHL ≤ 4.5 ns at 5 V, CL = 50 pF) and 3-state transition times (tPZH/tPZL ≤ 6.3 ns). While not a clocked device, this timing enables reliable use in asynchronous bus protocols such as ISA, VME, or custom parallel interfaces with >200 MHz toggle rate capability on individual lines.

Is the SN74ABTR2245DBRE4 RoHS compliant and lead-free?

Yes, the SN74ABTR2245DBRE4 is RoHS compliant and features a lead-free NIPDAU (nickel/palladium/gold) terminal finish, as documented in TI's Package Option Addendum. It carries a Moisture Sensitivity Level (MSL) rating of Level-1 (unlimited floor life at ≤30°C/60% RH) and is qualified for peak reflow temperatures up to 260°C, meeting J-STD-020 standards for lead-free assembly processes.