Texas Instruments SN74AUC1G125YZAR

Overview

SN74AUC1G125 from Texas Instruments is a single-channel 3-state bus buffer gate optimized for 1.8-V operation, delivering ±8-mA output drive, 2.5-ns maximum propagation delay at 1.8 V/30 pF, 0.8–2.7-V operating voltage range, and over-voltage tolerant I/Os supporting up to 3.6 V independent of VCC. It serves as a high-speed signal redriver in low-voltage digital interconnects.

For engineers reviewing the SN74AUC1G125 datasheet, SN74AUC1G125 pinout, SN74AUC1G125 application, or SN74AUC1G125 equivalent, key selection criteria include 3-state control timing (tdis = 3.1 ns max), Ioff-enabled partial power-down capability, ULTTL output structure for 50–65-Ω transmission line driving without external termination, and NanoFree™ DSBGA package compatibility with space-constrained PCB layouts.

Technical Context

The SN74AUC1G125 implements a noninverting 3-state buffer with active-low output-enable (OE) logic: output Y follows input A when OE is low, and enters high-impedance state when OE is high. Its ULTTL CMOS output stage provides matched sourcing/sinking capability and dynamic impedance control during transitions to suppress ringing on controlled-impedance lines up to 15 cm.

It supports true partial-power-down operation via Ioff circuitry, disabling all outputs and limiting back-drive current when VCC = 0 V. Input and output pins tolerate up to 3.6 V regardless of VCC level, enabling mixed-voltage interfacing between 1.8-V core logic and 3.3-V peripherals without level shifters.

Key Specifications

Pinout & Package

SN74AUC1G125 is available in three 5-pin packages: SOT-23 (DBV, 2.90 mm × 1.60 mm), SC70 (DCK, 2.00 mm × 1.25 mm), and NanoFree™ DSBGA (YZP, 1.39 mm × 0.89 mm). The YZP variant uses die-as-package construction for minimal footprint and thermal resistance (RθJB = 47.6 °C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC1G125DBVR and NC7SZ125P5X, the SN74AUC1G125 uniquely combines 1.8-V speed optimization (2.5 ns), Ioff-enabled power sequencing, and 3.6-V I/O tolerance-making it the only option for robust, high-speed, low-voltage interconnects requiring safe partial power-down and mixed-voltage resilience.

Availability

SN74AUC1G125 is available at Aetrix Electronics and suitable for high-speed memory interfaces, FPGA I/O expansion, portable display data channels, and industrial sensor signal conditioning requiring stable component supply across automotive, industrial, and consumer electronics programs.

Supply support for SN74AUC1G125 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 decades of leadership in high-performance logic and interface solutions.

The SN74AUC1G125 belongs to TI's AUC (Advanced Ultra-CMOS) sub-1-V logic family, engineered specifically for speed, signal integrity, and power efficiency in next-generation low-voltage digital interconnects.

FAQ

What is the maximum operating frequency supported by the SN74AUC1G125?

The SN74AUC1G125 supports data rates exceeding 250 MHz under optimal conditions (1.8 V, 15-pF load), with a maximum propagation delay of 2.5 ns at 1.8 V and 30-pF load. Its ULTTL output structure maintains signal fidelity on 50–65-Ω transmission lines up to 15 cm, enabling reliable operation at 500 Mbps in point-to-point configurations. Actual achievable frequency depends on layout, load, and supply stability.

Does the SN74AUC1G125 support partial power-down functionality?

Yes, the SN74AUC1G125 includes Ioff circuitry that disables all outputs and limits leakage current to ±10 µA when VCC = 0 V. This prevents damaging back-current flow into powered-down sections of a system, making the SN74AUC1G125 suitable for applications requiring safe power sequencing, such as hot-pluggable modules or multi-rail SoC subsystems.

Can the SN74AUC1G125 interface directly with 3.3-V logic signals?

Yes, the SN74AUC1G125 features over-voltage tolerant I/Os that accept and drive signals up to 3.6 V regardless of VCC level (0.8–2.7 V). This allows direct connection to 3.3-V peripherals without external level shifters-provided output current limits (±20 mA absolute max) and voltage ratings are observed per the Absolute Maximum Ratings table.

Which package options are available for the SN74AUC1G125, and what are their key mechanical differences?

The SN74AUC1G125 is offered in three packages: SOT-23 (DBV, 2.90 mm × 1.60 mm), SC70 (DCK, 2.00 mm × 1.25 mm), and NanoFree™ DSBGA (YZP, 1.39 mm × 0.89 mm). The YZP package uses the silicon die as the package, achieving the smallest footprint and lowest thermal resistance (RθJB = 47.6 °C/W), while DBV offers highest manufacturability in standard pick-and-place processes.

How should unused inputs be handled on the SN74AUC1G125?

All unused inputs on the SN74AUC1G125-including A and OE-must be tied to a valid logic level (VCC or GND) to prevent floating, which can cause excessive power consumption, oscillation, or undefined output states. A 10-kΩ pullup or pulldown resistor is recommended for OE to ensure high-impedance state during power-up; unused A inputs may be tied directly to VCC or GND based on functional intent.