Texas Instruments SN74LV126ADGVR

Overview

SN74LV126ADGVR from Texas Instruments is a quadruple bus buffer gate with 3-state outputs, designed for 2V–5.5V V_CC operation in mixed-voltage digital systems. It provides independent channel control via four OE inputs, delivers ≤6.5ns propagation delay at 5V, supports I_off for live insertion and partial power-down, and features 5.5V-tolerant inputs - enabling level translation from higher-voltage buses to 3.3V or 2.5V logic domains in network switch backplanes.

For engineers reviewing the SN74LV126ADGVR datasheet, SN74LV126ADGVR pinout, SN74LV126ADGVR application, or SN74LV126ADGVR equivalent, this device is selected for high-density, low-noise bus buffering where output ground bounce (V_OLP < 0.8V) and VOH undershoot (V_OHV > 2.3V) must be minimized in 3.3V industrial control and set-top-box signal routing.

Technical Context

The SN74LV126ADGVR implements four identical noninverting buffer channels, each with dedicated 3-state output-enable (OE) control and CMOS input structure. Its I_off specification ensures isolation during power sequencing, while 5.5V input tolerance allows interfacing with legacy 5V logic without external level shifters.

Propagation delay varies with supply voltage and load: 6.5ns max at V_CC = 5V/CL = 15pF, 9.5ns at V_CC = 3.3V/CL = 15pF, and 15.5ns at V_CC = 2.5V/CL = 15pF. Output drive strength is rated ±35mA per channel, with total device current limited to ±70mA.

Key Specifications

Pinout & Package

SN74LV126ADGVR uses a 14-pin TVSOP (Thin Very Small Outline Package) with 0.5mm pitch, 6.8mm × 4.0mm body size, and 1.2mm max height - optimized for high-density PCB layouts in space-constrained consumer and telecom equipment.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC126APWR and 74AUP1G125GW,125, the SN74LV126ADGVR uniquely combines quad integration, 5.5V input tolerance, and 2V–5.5V operation - making it the only option among the three that supports true mixed-voltage bus bridging without redesigning power or interface circuitry.

Availability

SN74LV126ADGVR is available at Aetrix Electronics and suitable for network switch backplanes, set-top box video buses, and industrial PLC I/O modules requiring stable component supply across extended temperature ranges and mixed-voltage signal domains.

Supply support for SN74LV126ADGVR 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 and embedded processing solutions, with over 90 years of innovation in precision logic, power management, and signal chain technologies.

The SN74LV126A belongs to TI's LV (Low-Voltage) logic family, engineered for robust performance across wide supply ranges and mixed-voltage system interconnects - specifically targeting industrial, telecom, and consumer applications demanding reliability and compatibility.

FAQ

What is the maximum propagation delay of SN74LV126ADGVR at 3.3V supply?

The maximum propagation delay (t_pd) for SN74LV126ADGVR is 9.5ns at V_CC = 3.3V with 15pF load capacitance and 25°C ambient temperature, as specified in Section 5.7 of the official datasheet. This value applies to the A→Y path under recommended operating conditions and ensures timing margin for 100MHz bus operations in real-world layouts.

Does SN74LV126ADGVR support 5V input signals when powered at 3.3V?

Yes, SN74LV126ADGVR supports input voltages up to 5.5V regardless of V_CC level - confirmed in Section 5.3 (Recommended Operating Conditions) and Section 7.3 (Feature Description). When V_CC = 3.3V, its inputs remain fully 5V-tolerant, enabling direct connection to 5V microcontrollers or legacy peripherals without external level-shifting components.

What is the function of the I_off specification in SN74LV126ADGVR?

The I_off specification (±5µA maximum at V_CC = 0V) ensures that SN74LV126ADGVR blocks current flow between powered and unpowered sections of a system. This enables safe live insertion, partial power-down modes, and back-drive protection - critical for modular systems like hot-swappable network line cards where individual boards may be powered independently.

Which package type does SN74LV126ADGVR use, and what are its key mechanical dimensions?

SN74LV126ADGVR uses a 14-pin TVSOP (Thin Very Small Outline Package) with package drawing DGV. Its nominal dimensions are 6.8mm length × 4.0mm width × 1.2mm maximum height, with 0.5mm lead pitch. These compact metrics support high-density routing in space-constrained applications such as set-top boxes and portable industrial HMIs.

How should unused inputs be handled on SN74LV126ADGVR?

All unused inputs on SN74LV126ADGVR must be tied to a valid logic level - either V_CC or GND - as stated in Section 5.3 Note (1) and Section 8.4.1. Floating CMOS inputs can cause increased ICC, erratic switching, or latch-up. For example, an unused OE input should be pulled low to ensure its associated buffer remains disabled and does not contribute to dynamic power consumption.