Texas Instruments SN74ABT2245DW

Overview

SN74ABT2245DW 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 direction control (DIR), output enable (OE), 25-Ω integrated series resistors on B-port outputs, 5-V operation, and operates from –40°C to 85°C in a 20-pin SOIC (DW) package. Used in industrial backplane interfaces and legacy system bus bridging.

For engineers reviewing the SN74ABT2245DW datasheet, SN74ABT2245DW pinout, SN74ABT2245DW application, or SN74ABT2245DW equivalent, key selection criteria include 3-state isolation timing, B-port sink capability (12 mA), VCC=4.5–5.5 V compliance, power-up high-impedance behavior, and SOIC-DW thermal performance (θJA = 97°C/W).

Technical Context

The SN74ABT2245DW implements a dual-bus transceiver architecture with independent DIR and OE controls: DIR selects data flow direction (A→B or B→A), while OE places all outputs in high-impedance state. Its EPIC-II^B BiCMOS process enables low power dissipation and robust latch-up immunity (>500 mA per JESD-17).

It integrates 25-Ω series resistors on all eight B-port outputs to suppress overshoot/undershoot without external components, while A-port outputs support higher drive strength (64 mA sink). The device enters high-impedance during power-up/down when VCC is below 2.1 V, and requires OE pull-up above that threshold for guaranteed isolation.

Key Specifications

Pinout & Package

SN74ABT2245DW uses a 20-pin SOIC (DW) package, 7.5 mm × 12.8 mm body, 1.27 mm lead pitch, 2.65 mm max height, RoHS-compliant NiPdAu finish, and MSL Level-1 rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ABT2245DW, SN74ABT245DW adds design flexibility via dual OE but increases control wiring; 74LVTH245MTR reduces power and voltage but sacrifices integrated termination and 5-V compatibility - making SN74ABT2245DW optimal for cost-sensitive, 5-V industrial bus isolation.

Availability

SN74ABT2245DW is available at Aetrix Electronics and suitable for industrial backplane interfaces, legacy system bus bridging, test equipment data capture, and programmable logic I/O expansion requiring stable component supply and long-term manufacturing continuity.

Supply support for SN74ABT2245DW 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 delivering analog, embedded processing, and logic solutions with over 50 years of industrial-grade product experience.

The SN74ABT2245DW belongs to TI's ABT logic family, engineered for high-speed, low-noise 5-V bus interfacing in industrial and instrumentation applications where signal integrity and power-up safety are critical.

FAQ

What is the maximum recommended operating temperature for SN74ABT2245DW?

The SN74ABT2245DW is characterized for operation from –40°C to +85°C. This industrial temperature range is validated per manufacturer specifications and applies across the full VCC range (4.5 V to 5.5 V). Thermal derating is not required within this envelope, and the SOIC-DW package's 97°C/W θJA ensures safe junction temperatures under typical load conditions at 85°C ambient.

Does SN74ABT2245DW require external series resistors on the B-port outputs?

No, SN74ABT2245DW does not require external series resistors on the B-port outputs. Each B-port output includes an integrated 25-Ω series resistor, explicitly designed to reduce overshoot and undershoot in high-speed bus applications. This feature eliminates the need for discrete termination components, simplifying layout and reducing bill-of-materials cost while maintaining signal integrity on the B bus.

How does SN74ABT2245DW behave during power-up and power-down sequences?

During power-up or power-down, SN74ABT2245DW enters a high-impedance state when VCC is between 0 V and 2.1 V. To ensure reliable high-impedance above 2.1 V, the OE pin must be tied to VCC through a pullup resistor. The minimum resistor value depends on the driver's current-sourcing capability - typically 10 kΩ suffices for most microcontroller or FPGA GPIO drivers. This behavior prevents bus contention in systems with asynchronous power sequencing.

What is the propagation delay from A-port to B-port for SN74ABT2245DW at 5 V?

At VCC = 5 V and TA = 25°C with CL = 50 pF, the SN74ABT2245DW exhibits tPLH (A→B) of 1 ns minimum and 3.8 ns maximum, and tPHL (A→B) of 1 ns minimum and 4.5 ns maximum. These values are measured under standard loading and define the worst-case timing window for data valid-to-output transitions, supporting reliable operation in 25-MHz bus systems with adequate setup/hold margins.

Is SN74ABT2245DW pin-compatible with other packages in the same family?

Yes, SN74ABT2245DW shares identical pinout and functionality with other 20-pin variants in the SN74ABT2245 family, including SN74ABT2245DBR (SSOP), SN74ABT2245N (PDIP), and SN74ABT2245PW (TSSOP). All variants use the same top-view pin numbering, DIR/OE logic, and electrical interface - enabling direct PCB footprint substitution where package height, thermal, or assembly constraints allow.