Texas Instruments SN74LV244ADBRE4

Overview

SN74LV244ADBRE4 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 interfacing, and includes Ioff for partial-power-down operation - enabling use in server backplanes and industrial control I/O expansion.

For engineers reviewing the SN74LV244ADBRE4 datasheet, SN74LV244ADBRE4 pinout, SN74LV244ADBRE4 application, or SN74LV244ADBRE4 equivalent, key selection criteria include its 20-pin SSOP package, 3-state drive capability up to ±16 mA per output, ground-bounce and undershoot performance at 3.3 V, thermal resistance (RθJA = 118.2°C/W), and compatibility with legacy 5-V and modern 3.3-V/2.5-V logic domains.

Technical Context

The SN74LV244ADBRE4 implements two independent 4-bit noninverting buffer sections, each controlled by a dedicated OE input. Its balanced CMOS 3-state outputs provide symmetrical sourcing and sinking capability (±16 mA at VCC ≥ 4.5 V), enabling robust driving of capacitive loads ≤50 pF while maintaining signal integrity across PCB traces and connectors.

It integrates Ioff circuitry that disables all outputs when VCC = 0 V, preventing backfeeding during power sequencing. Input thresholds scale with VCC (VIH = 0.7×VCC, VIL = 0.3×VCC), supporting interoperability between 2.5-V, 3.3-V, and 5-V logic families without level shifters.

Key Specifications

Pinout & Package

SN74LV244ADBRE4 is housed in a 20-pin SSOP (DB) package measuring 7.2 mm × 7.8 mm, with gull-wing leads and standard JEDEC MO-153 footprint. The thermal pad is absent - no exposed pad grounding required.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC244APWR and 74LVX244M, the SN74LV244ADBRE4 uniquely combines 2–5.5-V operation, Ioff protection, and SSOP packaging - making it the only option among the three qualified for 5-V bus interfacing, hot-swap I/O modules, and space-constrained industrial PCBs requiring mixed-voltage resilience.

Availability

SN74LV244ADBRE4 is available at Aetrix Electronics and suitable for server backplanes, LED display drivers, telecom line cards, and industrial motor-drive I/O expansion requiring stable component supply across extended temperature and mixed-voltage conditions.

Supply support for SN74LV244ADBRE4 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 logic solutions for industrial, automotive, and communications markets.

The SN74LV244A product line delivers high-drive, low-noise 3-state buffers optimized for bus loading, signal integrity preservation, and mixed-voltage system interconnect - targeting infrastructure equipment where reliability, thermal resilience, and design longevity are critical.

FAQ

What is the maximum capacitive load SN74LV244ADBRE4 can drive while meeting all specifications?

The SN74LV244ADBRE4 is characterized and guaranteed to meet all electrical and timing specifications with a total load capacitance ≤50 pF, as verified in the Switching Characteristics tables for VCC = 2.5 V, 3.3 V, and 5 V. Driving larger loads increases propagation delay and may degrade VOLP/VOHV performance; for >50-pF applications, signal integrity simulation and empirical validation are recommended. The SN74LV244ADBRE4 datasheet specifies CL = 50 pF as the test condition for tpd, ten, and tdis parameters.

Does SN74LV244ADBRE4 support hot-swap operation, and how is this implemented?

Yes, SN74LV244ADBRE4 supports hot-swap operation via its Ioff feature: when VCC = 0 V, all outputs enter high-impedance state with leakage ≤5 µA, preventing backfeeding into powered subsystems. This is confirmed in Section 6.5 Electrical Characteristics (Ioff parameter) and Section 8.3.3 of the datasheet. To implement safely, tie OE pins to VCC through pull-up resistors and ensure mechanical insertion sequence places GND before VCC and VCC before signal lines.

What is the recommended bypass capacitor configuration for SN74LV244ADBRE4?

Texas Instruments recommends a 0.1-μF ceramic capacitor placed physically adjacent to the VCC (Pin 20) and GND (Pin 10) pins of the SN74LV244ADBRE4, as stated in Section 9.3 Power Supply Recommendations. For systems with high-frequency noise, paralleling a 1-μF capacitor improves broadband suppression. The capacitor must be mounted directly on the top layer with short, wide traces to minimize inductance - layout guidelines are detailed in Section 9.4.

Can unused inputs on SN74LV244ADBRE4 be left floating, and what are the risks?

No, unused inputs on SN74LV244ADBRE4 must never be left floating. Section 6.3 Recommended Operating Conditions and Section 8.3.2 explicitly require all unused CMOS inputs to be terminated to VCC or GND to prevent oscillation, excessive power consumption, and potential device damage. A 10-kΩ pull-up or pull-down resistor is recommended if dynamic control is needed; direct connection is acceptable for static termination. Floating inputs violate absolute maximum ratings and invalidate functional guarantees.

How does SN74LV244ADBRE4 handle mixed-voltage interfacing between 3.3-V and 5-V logic domains?

SN74LV244ADBRE4 enables mixed-voltage interfacing through scalable input thresholds (VIH = 0.7×VCC, VIL = 0.3×VCC) and overvoltage-tolerant inputs rated to 5.5 V regardless of VCC. When powered at 3.3 V, it reliably detects 5-V logic highs because VIH(min) = 2.31 V - well below 5 V. This is documented in Table 6-3 and Section 8.3.2. No external level shifters are needed, simplifying interconnect between FPGA (3.3 V) and legacy ASICs (5 V).