Texas Instruments SN74LVC2244APWR

Overview

SN74LVC2244APWR from Texas Instruments is an octal buffer/line driver with 3-state outputs, designed for 1.65 V to 3.6 V V_CC operation. It features two independent 4-bit sections (1A–1Y and 2A–2Y), dual output-enable inputs (1OE, 2OE), 5.5 ns max propagation delay at 3.3 V, 26-Ω integrated output series resistance, and 5.5 V-tolerant inputs - enabling use in mixed-voltage 3.3 V/5 V system interfacing, such as microcontroller I/O expansion in industrial control panels.

For engineers reviewing the SN74LVC2244APWR datasheet, SN74LVC2244APWR pinout, SN74LVC2244APWR application, or SN74LVC2244APWR equivalent, key selection criteria include 3-state drive capability, I_off support for live insertion, ±12 mA output sink/source strength, overvoltage-tolerant inputs, and thermal performance under 125°C ambient conditions.

Technical Context

The SN74LVC2244APWR implements a dual 4-bit noninverting buffer architecture with independent 3-state control per section. Each output includes on-die 26-Ω series termination to suppress overshoot/undershoot without external resistors, and supports mixed-mode signal operation - accepting 5.5 V inputs while powered from 1.65–3.6 V V_CC.

I_off circuitry ensures high-impedance isolation of inputs and outputs when V_CC = 0 V, enabling safe partial-power-down and back-drive protection. Latch-up immunity exceeds 250 mA per JESD 17, and ESD robustness meets 2000-V HBM, 200-V MM, and 1000-V CDM standards.

Key Specifications

Pinout & Package

TSSOP-20 package (6.50 mm × 4.40 mm body size, 0.65 mm pitch), lead-free with NiPdAu finish, MSL Level-1 (unlimited floor life).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC244APWR and 74LVC2244PW,118, the SN74LVC2244APWR uniquely combines I_off, 125°C operation, and 2000-V HBM in a TSSOP-20 package - making it the only option qualified for industrial hot-swap and extended-temperature deployment.

Availability

SN74LVC2244APWR is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, automotive body control modules, and medical patient monitor interfaces requiring stable component supply across long production lifecycles.

Supply support for SN74LVC2244APWR 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 connectivity technologies with over 50 years of innovation in industrial, automotive, and communications markets.

The SN74LVC2244APWR belongs to TI's LVC logic family - engineered for low-voltage, high-speed, mixed-signal interfacing in space-constrained, thermally demanding applications where reliability and voltage flexibility are critical.

FAQ

What is the maximum operating temperature for the SN74LVC2244APWR?

The SN74LVC2244APWR is rated for continuous operation from –40°C to +125°C ambient temperature. This specification is validated per JEDEC JESD78 and confirmed in the device's Recommended Operating Conditions table (Section 7.3). The thermal metrics - including R_θJA = 102.5°C/W for the PW package - ensure reliable performance in enclosed industrial enclosures without forced airflow. Always verify board-level thermal design using the provided ψ_JT and ψ_JB parameters.

Does the SN74LVC2244APWR support 5 V input signals while powered at 3.3 V?

Yes, the SN74LVC2244APWR supports input voltages up to 5.5 V regardless of V_CC level - a feature explicitly documented in Section 7.3 (Recommended Operating Conditions) and Feature Description (Section 9.3). This overvoltage tolerance enables direct connection to 5 V logic families without external level-shifting components. Input clamp current remains within safe limits (±50 mA) per Absolute Maximum Ratings, and no additional protection diodes are required.

How does the I_off feature function in the SN74LVC2244APWR?

The I_off feature in the SN74LVC2244APWR disables both input and output circuitry when V_CC = 0 V, limiting leakage current to ±10 μA (Section 7.5). This prevents back-driving of powered circuitry during live insertion or partial power-down - a requirement for modular backplane systems. The behavior is verified across temperature (–40°C to 125°C) and is independent of OE pin state. TI confirms this functionality in Section 9.3 and Application Information (Section 10.1).

What is the purpose of the 26-Ω series resistance on SN74LVC2244APWR outputs?

The SN74LVC2244APWR integrates 26-Ω series resistors on all eight outputs to damp signal reflections and reduce overshoot/undershoot - eliminating the need for external termination. As stated in Features (Section 1) and Detailed Description (Section 9.1), this design reduces VOHV (>2 V) and VOLP (<0.8 V) at 3.3 V, improving signal integrity on unterminated PCB traces up to 15 cm. The value is process-trimmed and temperature-compensated, ensuring consistent performance across voltage and temperature ranges.

Can unused inputs on the SN74LVC2244APWR be left floating?

No, unused inputs on the SN74LVC2244APWR must be tied to V_CC or GND - never left floating. Section 7.3 notes that "all unused inputs… must be held at V_CC or GND to ensure proper device operation," and Layout Guidelines (Section 12.1) reinforce this to prevent undefined logic states, increased ICC, or EMI. TI's application report SCBA004 details risks of floating CMOS inputs. For SN74LVC2244APWR, tie unused A inputs to GND (for low default) or V_CC (for high default) using ≤10 kΩ resistors.