Texas Instruments SN74LV244ADW

Overview

SN74LV244ADW from Texas Instruments is an octal 3-state buffer/driver IC designed for bidirectional signal buffering in bus-oriented systems. It features dual 4-bit groups with independent output-enable (OE) controls, operates from 2 V to 5.5 V, delivers ≤6.5 ns propagation delay at 5 V, supports mixed-mode voltage operation, and includes Ioff for partial-power-down mode - used in server memory address buffering and telecom backplane interface isolation.

For engineers reviewing the SN74LV244ADW datasheet, SN74LV244ADW pinout, SN74LV244ADW application, or SN74LV244ADW equivalent, key selection considerations include its 20-pin SOIC (DW) package, 3.3-V/5-V logic compatibility, ±16-mA drive strength, ground-bounce/undershoot performance, and dual-OE control architecture for flexible bus partitioning.

Technical Context

The SN74LV244ADW implements two independent 4-bit noninverting buffer sections, each with dedicated active-low output-enable inputs (1OE, 2OE). Its balanced CMOS 3-state outputs support high-impedance, sourcing, and sinking states with matched drive capability (±16 mA at VCC = 4.5–5.5 V).

It uses standard CMOS inputs with ≤2.3 pF input capacitance and supports mixed-voltage interfacing across ports - enabling connection between 3.3-V controllers and 5-V peripherals without level shifters. Ioff circuitry ensures <5 µA power-off leakage when VCC = 0 V.

Key Specifications

Pinout & Package

SN74LV244ADW is housed in a 20-pin SOIC (DW) package measuring 12.80 mm × 10.3 mm, with standard 0.050″ (1.27 mm) lead pitch and gull-wing leads compatible with automated PCB assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal 3-state buffer applications.

Compared with SN74LV244ADW, SN74LVC244APW offers faster speed in 3.3-V domains but sacrifices 5-V interoperability, while 74AC244N provides broader voltage tolerance without Ioff - making SN74LV244ADW the only choice for mixed-voltage, hot-pluggable, or low-quiescent-power bus isolation.

Availability

SN74LV244ADW is available at Aetrix Electronics and suitable for server motherboard design, telecom infrastructure backplanes, and motor-drive control boards requiring stable component supply across extended product lifecycles.

Supply support for SN74LV244ADW 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 U.S.-based semiconductor company specializing in analog and embedded processing solutions, with leadership in logic, power management, and signal chain technologies.

The SN74LV244ADW belongs to TI's LV (Low-Voltage) logic family, engineered for high-speed, low-power, mixed-voltage interfacing in computing, communications, and industrial automation systems.

FAQ

What is the maximum operating temperature for the SN74LV244ADW?

The SN74LV244ADW is rated for continuous operation from –40°C to +125°C ambient temperature. This specification is validated per JEDEC JESD78 and applies to the SOIC (DW) package under recommended operating conditions, including proper PCB thermal relief and airflow. The SN74LV244ADW maintains full electrical performance across this range, supporting deployment in enclosed telecom chassis and motor-drive enclosures without derating.

Does the SN74LV244ADW support 5-V tolerant inputs when operated at 3.3 V VCC?

Yes, the SN74LV244ADW supports 5-V tolerant inputs across its full VCC range (2 V to 5.5 V). When VCC = 3.3 V, inputs accept VI up to 5.5 V without damage or functional degradation - confirmed by absolute maximum ratings (VI max = 7 V) and verified in mixed-mode operation testing. This enables direct interfacing between 3.3-V FPGAs and legacy 5-V peripherals without external level shifters, a key feature of the SN74LV244ADW.

Can unused inputs on the SN74LV244ADW be left floating?

No, unused inputs on the SN74LV244ADW must never be left floating. TI specifies that all unused CMOS inputs be terminated to either VCC or GND to prevent undefined logic states, excessive power consumption, and potential oscillation. A 10-kΩ pullup or pulldown resistor is recommended for uncommitted inputs - a requirement explicitly stated in the SN74LV244ADW datasheet Section 6.3 and reinforced in Application Report SCBA004.

What is the purpose of the Ioff feature in the SN74LV244ADW?

The Ioff feature in the SN74LV244ADW disables all outputs and limits input/output leakage to <5 µA when VCC = 0 V. This prevents current backflow from live system buses into a powered-down section - critical for hot-swap capability in modular servers and telecom line cards. Unlike standard 3-state logic, Ioff ensures safe isolation even when other rails remain active, a defining characteristic of the SN74LV244ADW in backplane applications.

How does the SN74LV244ADW handle ground bounce and output undershoot?

The SN74LV244ADW is characterized for low ground bounce (VOLP < 0.8 V at VCC = 3.3 V) and output undershoot (VOHV > 2.3 V at VCC = 3.3 V), measured under worst-case switching conditions. These parameters reflect internal output stage optimization and reduced simultaneous switching noise - directly improving signal integrity in dense PCB layouts. Designers leverage these specs in the SN74LV244ADW to relax layout constraints on shared ground planes and reduce need for additional decoupling.