Texas Instruments SN74LV125ATDBR

Overview

SN74LV125ATDBR 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 features four independent channels, TTL-compatible inputs, 4.5–5.5 V operation, 3.8 ns typical propagation delay at 5 V, and Ioff support for partial-power-down mode. It is commonly deployed in industrial control backplanes and microcontroller peripheral expansion interfaces.

For engineers reviewing the SN74LV125ATDBR datasheet, SN74LV125ATDBR pinout, SN74LV125ATDBR application, or SN74LV125ATDBR equivalent, key selection criteria include 3-state output timing (tpd/ten/tdis), mixed-voltage interface capability, ground bounce (VOLP) and undershoot (VOHV) performance, Ioff leakage under power-off conditions, and SSOP-14 package thermal and layout compatibility.

Technical Context

The SN74LV125ATDBR implements four identical non-inverting buffer stages, each with an active-low 3-state output-enable (OE) input. Each channel operates independently: when OE is low, the Y output follows the A input; when OE is high, Y enters high-impedance state. The device supports mixed-mode voltage operation - inputs tolerate TTL levels while outputs swing rail-to-rail within VCC.

Its Ioff circuitry actively disables all outputs during power-down, limiting current backflow to ≤5 µA per I/O terminal when VCC = 0 V and VI/VO = 0–5.5 V. Absolute maximum ratings permit up to 7 V on VCC or any I/O, and ESD robustness meets ±2000 V HBM and ±1000 V CDM per JEDEC standards.

Key Specifications

Pinout & Package

SN74LV125ATDBR uses a 14-pin SSOP (Shrink Small Outline Package) with 0.65 mm pitch, 6.20 mm × 7.80 mm body size, and 2.0 mm max height. The package includes exposed leadframe for thermal dissipation and is RoHS-compliant with NIPDAU lead finish and MSL Level-1 rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV125ATDBR, SN74LVC125APWR offers better speed at 3.3 V but cannot replace it in 5-V/TTL systems, while 74ACT125SCX delivers higher drive current but sacrifices Ioff protection and mixed-voltage flexibility - making SN74LV125ATDBR uniquely suited for industrial hot-plug and mixed-rail applications.

Availability

SN74LV125ATDBR is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, and test equipment design requiring stable component supply, long-term lifecycle support, and RoHS-compliant SSOP packaging.

Supply support for SN74LV125ATDBR 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 expertise in industrial-grade interface ICs and broad portfolio support.

The SN74LV125ATDBR belongs to TI's LV logic family, designed specifically for robust 5-V digital interfacing in harsh environments - emphasizing low ground bounce, Ioff safety, and wide temperature operation.

FAQ

What is the recommended power supply decoupling for SN74LV125ATDBR?

Place a 0.1 µF ceramic capacitor between VCC (pin 14) and GND (pin 7), located within 1 cm of the package. For systems with heavy switching loads, add a 4.7 µF bulk capacitor nearby. This minimizes supply noise and suppresses ground bounce (VOLP), which is critical given SN74LV125ATDBR's specified <0.8 V dynamic ground excursion at 5 V.

Does SN74LV125ATDBR support hot-swap operation?

Yes - SN74LV125ATDBR incorporates Ioff circuitry that limits power-off leakage to ≤5 µA per I/O when VCC = 0 V and VI/VO = 0–5.5 V. This prevents damaging back-current during live insertion/removal, making SN74LV125ATDBR suitable for modular backplane and hot-plug peripheral designs.

Can SN74LV125ATDBR interface directly with TTL logic inputs?

Yes - SN74LV125ATDBR inputs are explicitly TTL-voltage compatible: VIH(min) = 2.0 V and VIL(max) = 0.8 V over 4.5–5.5 V VCC. This allows direct connection to standard 5-V TTL outputs without level shifting, unlike LVC-family buffers that require ≥2.0 V for VIH only at 3.3 V.

What is the maximum operating frequency supported by SN74LV125ATDBR?

While SN74LV125ATDBR has no defined maximum clock frequency, its 3.8 ns typical propagation delay (tpd) and 7.5 ns max tpd (–40°C to +125°C, CL = 15 pF) support reliable operation in bus systems up to ~100 MHz. System-level timing must account for ten (enable delay) and tdis (disable delay), both ≤8.5 ns max over temperature.

Is SN74LV125ATDBR pin-compatible with other 14-pin bus buffers?

SN74LV125ATDBR shares the same 14-pin SSOP (DB) footprint and functional pinout with industry-standard quad 3-state buffers like 74LS125 and 74HC125. However, voltage tolerances, drive strength, and Ioff behavior differ - verify VIH/VIL thresholds and power-down behavior before drop-in replacement.