Texas Instruments SN74LV244ATPWR

Overview

SN74LV244ATPWR from Texas Instruments is an octal buffer/driver with 3-state outputs, designed for memory-address, clock, and bus-oriented applications. It operates from 4.5 V to 5.5 V, features TTL-voltage-compatible inputs, Ioff partial-power-down support, and delivers typical propagation delay of 5.4 ns at 5 V in TSSOP-20 package.

For engineers reviewing the SN74LV244ATPWR datasheet, SN74LV244ATPWR pinout, SN74LV244ATPWR application, or SN74LV244ATPWR equivalent, key selection criteria include 3-state output control timing (tPLZ/tPHZ ≤ 8 ns), Ioff leakage (<5 µA), and compatibility with mixed-mode voltage interfaces on all ports.

Technical Context

This device integrates two independent 4-bit noninverting buffers, each with dedicated output-enable (OE) inputs-1OE controls Y1–Y4, 2OE controls Y1'–Y4'. Output enable is active-low: when OE is low, data passes from A inputs to Y outputs; when high, outputs enter high-impedance state.

It supports partial-power-down via Ioff circuitry that disables outputs and prevents backflow current during power-off conditions. Input thresholds meet TTL levels (VIL = 0.8 V, VIH = 2 V) across –40°C to 85°C, and dynamic noise parameters (VOLP < 0.8 V, VOHV > 2.3 V) are specified at VCC = 5 V, TA = 25°C.

Key Specifications

Pinout & Package

TSSOP-20 (PW) package: 6.5 mm × 4.4 mm, 1.2 mm max height, 0.65 mm lead pitch, gull-wing leads, RoHS-compliant NiPdAu finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV244ATPWR, SN74LVC244APWR offers better performance at lower voltage but sacrifices TTL compatibility, while 74ACT244SCX provides superior speed and drive but omits Ioff protection-making SN74LV244ATPWR the optimal choice for robust 5-V industrial bus buffering with power sequencing flexibility.

Availability

SN74LV244ATPWR is available at Aetrix Electronics and suitable for memory address buffering, clock distribution, and industrial backplane interface applications requiring stable component supply and long-term industrial temperature support.

Supply support for SN74LV244ATPWR 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 company specializing in analog, embedded processing, and logic solutions, with decades of leadership in industrial and automotive-grade logic families.

The SN74LV244ATPWR belongs to TI's LV-A series of low-voltage, high-speed logic devices engineered for robust 5-V system interfacing, emphasizing noise immunity, power-down safety, and bus contention control in industrial control and computing infrastructure.

FAQ

What is the recommended power-up sequence for SN74LV244ATPWR to avoid bus contention?

During power-up, tie both 1OE and 2OE to VCC through a pullup resistor (minimum value determined by driver sink capability). This ensures outputs remain in high-impedance state until system logic asserts valid control signals. The SN74LV244ATPWR Ioff feature further protects against backflow if inputs are driven before VCC stabilizes, making it safe for asynchronous power sequencing in multi-rail systems.

Does SN74LV244ATPWR support mixed-voltage operation between input and output sides?

Yes, SN74LV244ATPWR supports mixed-mode voltage operation on all ports. Inputs accept TTL-level signals (0.8 V/2.0 V) across full 0–5.5 V range, while outputs swing rail-to-rail (0 to VCC) and tolerate up to 5.5 V in 3-state mode. This allows interfacing a 3.3-V controller to a 5-V bus segment using SN74LV244ATPWR as a level-aware buffer without external translators.

What is the maximum capacitive load SN74LV244ATPWR can drive while maintaining specified timing?

SN74LV244ATPWR is characterized for CL = 15 pF and CL = 50 pF loads. At 5 V, tPLH/tPHL remains ≤8.9 ns up to 50 pF. For heavier loads, propagation delay increases linearly-designers should limit total net capacitance (including trace, stub, and receiver input) to ≤50 pF to stay within datasheet timing margins and avoid excessive ground bounce (VOLP < 0.8 V guaranteed only at CL = 50 pF).

How does the Ioff feature of SN74LV244ATPWR protect the device during partial power-down?

The Ioff circuitry in SN74LV244ATPWR actively disables all outputs when VCC = 0 V, limiting input/output leakage to <5 µA even with pins biased at 0–5.5 V. This prevents damaging reverse current flow from powered sections into unpowered ones-critical in modular systems where one board may be hot-plugged or powered independently. SN74LV244ATPWR maintains this protection across –40°C to 85°C without external components.

Can SN74LV244ATPWR replace older 74LS244 devices in existing designs?

SN74LV244ATPWR is a functional and pin-compatible upgrade to 74LS244 in TSSOP-20, offering lower power (ICC < 20 µA vs. mA-range LS), higher noise immunity (VOLP < 0.8 V), and Ioff protection. However, note its 3.3-V tolerant inputs differ from LS TTL thresholds-verify that driving sources meet SN74LV244ATPWR's VIH = 2.0 V min requirement. No PCB changes are needed for footprint or pinout.