Texas Instruments SN74LV540ARGYR

Overview

SN74LV540ARGYR from Texas Instruments is an octal inverting 3-state buffer/driver IC designed for bus line driving and memory address register buffering in 2 V to 5.5 V systems. It features dual active-low output enables (OE1, OE2), 8 inverted outputs (Y1–Y8), and supports mixed-mode voltage translation with 5.5 V-tolerant inputs. Its 8.5 ns max propagation delay at 5 V and low ground bounce (<0.8 V) make it suitable for noise-sensitive industrial bus interfaces.

For engineers reviewing the SN74LV540ARGYR datasheet, SN74LV540ARGYR pinout, SN74LV540ARGYR application, or SN74LV540ARGYR equivalent, key selection considerations include its VQFN-20 (RGY) package with exposed thermal pad, Ioff partial-power-down capability, 35 mA per-output drive strength, and guaranteed operation from –40°C to +125°C across all supply voltages.

Technical Context

The SN74LV540ARGYR implements eight identical inverting buffer channels, each controlled by a two-input AND gate with active-low enables (OE1 and OE2). When either enable is high, all corresponding outputs enter high-impedance state; only when both are low do outputs actively drive inverted logic levels. This architecture enables flexible bus arbitration and bidirectional data isolation without external logic.

Its CMOS design provides rail-to-rail output swing (VOL ≤ 0.55 V at 4.5 V/16 mA, VOH ≥ 3.8 V), input overvoltage tolerance up to 5.5 V regardless of VCC, and Ioff protection that disables current flow when VCC = 0 V - critical for hot-swap and power sequencing in multi-rail systems.

Key Specifications

Pinout & Package

VQFN-20 (RGY) package: 4.50 mm × 3.50 mm body, 0.4 mm pitch, exposed thermal pad on underside for enhanced PCB heat dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV540ARGYR, SN74LVC541APWR offers faster timing but requires redesign for polarity; 74ALVC541PW delivers higher speed within a narrower voltage window and no Ioff - making SN74LV540ARGYR uniquely suited for mixed-voltage, hot-swap, and wide-temperature industrial deployments.

Availability

SN74LV540ARGYR is available at Aetrix Electronics and suitable for industrial transports, patient monitoring systems, and automotive infotainment applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74LV540ARGYR 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 for industrial, automotive, and communications markets.

The SN74LV540ARGYR belongs to TI's LV family of low-voltage CMOS logic devices, engineered specifically for robust mixed-signal interfacing in harsh environments with strict power sequencing and noise immunity requirements.

FAQ

What is the function of the dual output enable pins (OE1 and OE2) on the SN74LV540ARGYR?

The SN74LV540ARGYR uses OE1 and OE2 as active-low inputs to a two-input AND gate controlling all eight outputs. If either OE1 or OE2 is high, all Y1–Y8 outputs go to high-impedance state. Only when both are low do outputs actively drive inverted versions of A1–A8. This enables flexible bus partitioning - for example, using OE1 for global enable and OE2 for channel-group selection in multiplexed systems. The SN74LV540ARGYR datasheet confirms this behavior in Table 8-1 (Function Table).

Does the SN74LV540ARGYR support hot-swap or partial-power-down operation?

Yes, the SN74LV540ARGYR includes Ioff circuitry that limits input/output leakage to ≤5 µA when VCC = 0 V, preventing current backflow between powered and unpowered sections of a system. This feature is explicitly documented in Section 1 Features and Section 8.3 Feature Description. It makes the SN74LV540ARGYR suitable for hot-plug applications such as modular network switch cards or field-replaceable medical device modules where subsystems power up/down independently.

What is the maximum output current rating per pin for the SN74LV540ARGYR?

The SN74LV540ARGYR is rated for ±35 mA continuous output current per pin under recommended operating conditions, with a total device limit of ±70 mA across all outputs. This value is specified in Section 6.1 Absolute Maximum Ratings and verified in Section 6.3 Recommended Operating Conditions (IOL/IOH rows). Exceeding these limits risks thermal overstress or parametric shift. The SN74LV540ARGYR maintains VOL ≤ 0.55 V and VOH ≥ 3.8 V at 16 mA load, confirming robust drive capability within safe margins.

Can the SN74LV540ARGYR interface between 5 V inputs and a 3.3 V VCC supply?

Yes, the SN74LV540ARGYR accepts input voltages from 0 V to 5.5 V regardless of VCC level - a feature explicitly labeled "Supports Mixed-Mode Voltage operation on all ports" in Section 1 Features and detailed in Section 8.3. When VCC = 3.3 V, inputs at 5 V are safely clamped and translated to valid logic levels internally. This eliminates external level shifters in systems connecting legacy 5 V peripherals to modern 3.3 V controllers - a key use case confirmed in Section 9.1 Application Information for the SN74LV540ARGYR.

What thermal performance can be expected from the SN74LV540ARGYR in its RGY package?

The SN74LV540ARGYR in the VQFN-20 (RGY) package achieves RθJA = 35.1 °C/W, the lowest junction-to-ambient resistance among all offered packages (vs. 77.1–128.2 °C/W for others), due to its exposed thermal pad. Section 6.4 Thermal Information confirms this value applies to the RGY variant. With typical ICC = 20 µA and worst-case output switching, self-heating remains minimal - enabling reliable operation in compact, sealed enclosures without forced airflow. This thermal advantage is intrinsic to the SN74LV540ARGYR RGY construction.