Texas Instruments SN74LVT244BDW

Overview

SN74LVT244BDW from Texas Instruments is a 3.3-V ABT octal buffer/driver with 3-state outputs, designed for mixed-mode signal operation between 5-V inputs and 3.3-V V_CC. It features dual 4-bit drivers with independent output-enable (OE) controls, supports hot insertion via I_off and power-up 3-state, and operates from 2.7 V to 3.6 V - enabling use in battery-powered industrial backplanes and legacy 5-V system interfacing.

For engineers reviewing the SN74LVT244BDW datasheet, SN74LVT244BDW pinout, SN74LVT244BDW application, or SN74LVT244BDW equivalent, key selection criteria include its 3.3-V supply compatibility with 5-V tolerant inputs, 2.1 ns typical propagation delay at 3.3 V, ±100 μA I_off current for safe power-down, latch-up immunity >100 mA, and SOIC-20 (DW) package thermal resistance of 58°C/W.

Technical Context

The SN74LVT244BDW implements Advanced BiCMOS Technology (ABT) logic with TTL-compatible input thresholds (V_IL = 0.8 V, V_IH = 2 V) and 3.3-V CMOS output drive. Its two independent 4-bit sections each accept A-inputs and drive Y-outputs only when respective OE pins are low, placing outputs in high-impedance state otherwise.

It integrates I_off circuitry that disables outputs during V_CC = 0, preventing backflow current, and power-up 3-state logic that holds outputs high-Z during power ramping - both critical for hot-swap compliance. Absolute maximum ratings allow 7-V input/output tolerance in high-Z state and −0.5 V to 4.6 V V_CC range.

Key Specifications

Pinout & Package

SN74LVT244BDW uses a 20-pin SOIC (DW) package measuring 7.5 mm × 12.8 mm × 2.65 mm (max height), with 1.27 mm lead pitch and gull-wing leads. Thermal pad is not present; thermal performance relies on PCB copper area under body and leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVTH244ADW and 74ALVC244PW, the SN74LVT244BDW uniquely combines 5-V input tolerance, hot-swap readiness, and SOIC-20 manufacturability - making it the sole choice for retrofitting industrial backplanes where reliability and compatibility are non-negotiable.

Availability

SN74LVT244BDW is available at Aetrix Electronics and suitable for industrial backplane interface, legacy system bus extension, and hot-swappable module carrier applications requiring stable component supply, long-term lifecycle support, and TI-qualified production traceability.

Supply support for SN74LVT244BDW 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 connectivity solutions with over 90 years of innovation in industrial, automotive, and communications markets.

The SN74LVT244BDW belongs to TI's ABT logic family, engineered specifically for robust mixed-voltage interfacing in harsh industrial environments where signal integrity, power sequencing, and long-term reliability are critical.

FAQ

What is the maximum input voltage the SN74LVT244BDW can tolerate on its A-inputs?

The SN74LVT244BDW supports an input voltage range of −0.5 V to 7 V on all A-inputs, regardless of V_CC level. This allows direct connection to 5-V TTL or CMOS sources without external clamping or level-shifting circuitry - a key feature confirmed in the absolute maximum ratings table of the SCAS354J datasheet.

Does the SN74LVT244BDW require external pull-up resistors on its OE pins?

Yes - to ensure high-impedance outputs during power-up or power-down, OE pins should be tied to V_CC through a pull-up resistor. The minimum value depends on the driver's current-sinking capability; TI recommends values between 4.7 kΩ and 10 kΩ for typical 3.3-V rail conditions, as specified in the "description/ordering information" section.

Can the SN74LVT244BDW be used in hot-swap applications?

Yes - the SN74LVT244BDW is explicitly designed for hot-insertion use cases. Its I_off circuitry disables outputs when V_CC = 0, and power-up 3-state logic forces outputs into high-Z during supply ramping, preventing bus conflicts. These capabilities are validated per JESD 78 Class II latch-up testing and documented in the device's functional description.

What is the thermal resistance (θ_JA) of the SN74LVT244BDW in its SOIC-DW package?

The SN74LVT244BDW in the SOIC-20 (DW) package has a junction-to-ambient thermal resistance (θ_JA) of 58°C/W, measured per JESD 51-7. This value assumes standard JEDEC 2-layer test board conditions and confirms suitability for continuous operation at full drive strength up to +85°C ambient with adequate PCB copper area.

How does the SN74LVT244BDW handle ground bounce during switching?

The SN74LVT244BDW specifies typical output ground bounce (V_OLP) of <0.8 V at V_CC = 3.3 V and T_A = 25°C. This low value results from ABT process optimization and balanced output stage design, minimizing noise coupling into shared ground paths - a critical parameter verified in production characterization and listed in the "Features" section of SCAS354J.