Texas Instruments SN74LV125ATNSG4

Overview

SN74LV125ATNSG4 from Texas Instruments is a quadruple 3-state bus buffer gate IC used for bidirectional data isolation and bus driving in digital logic systems. It operates from 4.5 V to 5.5 V, delivers 3.8 ns typical propagation delay at 5 V, supports TTL-voltage-compatible inputs, and features Ioff partial-power-down protection. It is commonly deployed in industrial control backplanes and microcontroller peripheral expansion interfaces.

For engineers reviewing the SN74LV125ATNSG4 datasheet, SN74LV125ATNSG4 pinout, SN74LV125ATNSG4 application, or SN74LV125ATNSG4 equivalent, key selection criteria include 3-state output timing (tpd = 3.8 ns), mixed-mode voltage operation capability, ground bounce (VOLP < 0.8 V) and undershoot (VOHV > 2.3 V) performance at 5 V, and Ioff-enabled power sequencing robustness.

Technical Context

The SN74LV125ATNSG4 implements four independent non-inverting buffer channels, each with active-low 3-state output enable (OE). Its logic function follows a simple truth table: when OE is low, Y mirrors A; when OE is high, Y enters high-impedance state. All inputs tolerate TTL-level voltages (VIH ≥ 2 V, VIL ≤ 0.8 V) while operating from a 4.5–5.5-V supply.

It integrates Ioff circuitry that disables input/output leakage during partial power-down, preventing backflow current when VCC = 0 V. Thermal resistance is 47 °C/W (RGY package), and ESD robustness meets ±2000 V HBM and ±1000 V CDM per JEDEC standards.

Key Specifications

Pinout & Package

VQFN-14 (RGY) package: 3.5 mm × 3.5 mm, 0.5 mm pitch, exposed thermal pad, 1 mm max height. Requires soldering of thermal pad for thermal and mechanical reliability per SLUA271 guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV125ATNSG4, SN74LVC125APWR offers lower-voltage operation but forfeits 5-V input tolerance and extended temperature range, while 74ACT125SCX improves speed and drive but removes Ioff protection and high-temp qualification - making SN74LV125ATNSG4 the balanced choice for robust 5-V industrial bus isolation.

Availability

SN74LV125ATNSG4 is available at Aetrix Electronics and suitable for industrial PLC backplanes, automotive body control modules, and test equipment signal routing requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SN74LV125ATNSG4 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, with decades of heritage in industrial and automotive-grade logic families.

The SN74LV125ATNSG4 belongs to TI's LV (Low-Voltage) logic series, designed specifically for robust 5-V operation with enhanced noise immunity, power sequencing resilience, and extended temperature support in mission-critical embedded systems.

FAQ

What is the recommended power supply decoupling for SN74LV125ATNSG4?

Place a 100-nF X7R ceramic capacitor between VCC (pin 14) and GND (pin 7), located within 5 mm of the device. For systems with heavy simultaneous switching, add a 4.7-µF tantalum or aluminum polymer bulk capacitor nearby. The VQFN package's exposed thermal pad must be soldered to a solid ground plane to serve as both thermal relief and low-inductance return path - this is essential for meeting VOLP < 0.8 V and VOHV > 2.3 V specifications in the SN74LV125ATNSG4.

Does SN74LV125ATNSG4 support hot-swap or live insertion?

Yes, SN74LV125ATNSG4 supports hot-swap via its Ioff feature, which disables input/output leakage current to ≤5 µA when VCC = 0 V. This prevents damaging backflow current during insertion into a powered backplane. However, OE pins must be pulled high (e.g., via 10-kΩ resistors to VCC of the target board) before power application to guarantee outputs remain in high-impedance state during ramp-up - a requirement explicitly documented for SN74LV125ATNSG4 in Section 7.1 of its datasheet.

Can SN74LV125ATNSG4 interface directly with 3.3-V microcontrollers?

Yes, SN74LV125ATNSG4 supports mixed-mode voltage operation: its inputs accept 3.3-V logic levels (VIH ≥ 2 V, VIL ≤ 0.8 V) while powered from 5 V, and its outputs swing rail-to-rail (0 V to 5 V). To drive 3.3-V inputs safely, add a 1-kΩ series resistor at each Y output to limit current and prevent overstress - this configuration is validated in TI application note SCBA004 and confirmed for SN74LV125ATNSG4 in Section 5.3 Recommended Operating Conditions.

What is the maximum clock/data frequency supported by SN74LV125ATNSG4?

SN74LV125ATNSG4 is not a clocked device but a combinational buffer; its usable frequency depends on propagation delay and system setup/hold margins. With 3.8 ns typical tpd (A→Y) and 5.5 ns max over temperature, it supports clean data edges up to ~200 MHz in point-to-point configurations with proper termination. For 15-pF loads, rise/fall times are <3 ns, enabling reliable use in 50-MHz parallel buses (e.g., ISA-like expansions) and burst-mode ADC/DAC interfaces - all verified in SN74LV125ATNSG4 switching characteristics Table 5.6.

Is SN74LV125ATNSG4 RoHS compliant and lead-free?

Yes, SN74LV125ATNSG4 is RoHS compliant and lead-free. Per TI's PACKAGE OPTION ADDENDUM, the RGY package variant (including SN74LV125ATNSG4) uses NiPdAu or Sn lead finish, carries "Yes" RoHS status, and is rated MSL Level-1 with unlimited floor life at ≤30°C/60% RH. The part marking "VV125" and packaging code "RGYRG4" confirm compliance with JEDEC J-STD-020 and EU Directive 2011/65/EU - full details are published in TI's official materials database for SN74LV125ATNSG4.