onsemi MC74VHC125MEL

Overview

MC74VHC125MEL from ON Semiconductor is a high-speed CMOS quad bus buffer with independent 3-state control inputs (OE1–OE4), designed for bidirectional data bus isolation and signal routing in mixed-voltage systems. It operates from 2.0 V to 5.5 V, tolerates 7 V input voltages, delivers 3.8 ns typical propagation delay at 5 V, and supports 3-state output disable with ±25 mA drive capability - used in industrial control backplanes and 3.3 V/5 V level-translating I/O interfaces.

For engineers reviewing the MC74VHC125MEL datasheet, pinout, applications, or equivalent options, key selection criteria include its 2–5.5 V supply range, 7 V-tolerant inputs, 3-state timing (tPZL = 3.6 ns typ @ 5 V), noise immunity (28% VCC), and SOIC EIAJ package compatibility with legacy logic buses.

Technical Context

The MC74VHC125MEL implements four identical non-inverting buffers, each with an active-low 3-state enable (OE). Its three-stage internal architecture includes input conditioning, logic gating, and a robust output buffer stage that ensures stable switching and high noise immunity. Inputs are overvoltage-tolerant up to 7 V, enabling safe interfacing between 3.3 V and 5 V domains without external level shifters.

Each buffer features balanced tPLH/tPHL propagation delays and low output skew (<1.0 ns), critical for synchronous bus applications. The device complies with standard TTL and CMOS logic thresholds and exhibits latchup immunity >300 mA per JEDEC JESD78, supporting reliable operation in noisy industrial environments.

Key Specifications

Pinout & Package

MC74VHC125MEL is packaged in a 14-lead SOIC EIAJ (M suffix, Case 965), with 1.27 mm lead pitch, 10.2 mm × 5.3 mm body size, and gull-wing leads suitable for reflow soldering. Pin 1 is marked by a beveled corner or notch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC125APWR and 74AHC125PW, the MC74VHC125MEL uniquely combines 7 V input tolerance with sub-4 ns speed at 5 V and SOIC EIAJ packaging - making it optimal for legacy 5 V infrastructure upgrades requiring backward compatibility and transient resilience.

Availability

MC74VHC125MEL is available at Aetrix Electronics and suitable for industrial PLC backplanes, automotive body control modules, medical diagnostic equipment, and test & measurement instrumentation requiring stable component supply across extended temperature and voltage ranges.

Supply support for MC74VHC125MEL 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

ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power management, analog, logic, and discrete devices for automotive, industrial, and cloud infrastructure markets.

The MC74VHC125MEL belongs to the VHC (Very High Speed CMOS) logic family, engineered for pin-compatible migration from bipolar TTL while delivering CMOS-level power efficiency and robustness in harsh environments.

FAQ

What is the maximum input voltage rating for MC74VHC125MEL?

The MC74VHC125MEL supports DC input voltages from –0.5 V to +7.0 V, independent of VCC. This 7 V tolerance allows safe interfacing with 5 V signals even when powered from 3.3 V or 2.5 V supplies - a key advantage over standard LVC or HC logic families. The specification is validated across temperature (–55°C to +125°C) and appears in the Absolute Maximum Ratings table of the official ON Semiconductor datasheet.

Does MC74VHC125MEL support true 3-state operation with independent enables?

Yes, the MC74VHC125MEL provides four fully independent 3-state buffers, each with its own active-low output enable (OE1–OE4). When any OE is HIGH, its corresponding Y output enters high-impedance mode with leakage ≤±2.5 µA at 5.5 V. This enables selective bus segmentation - for example, disabling only Y2 while keeping Y1/Y3/Y4 active - without affecting other channels' logic states.

What package type does MC74VHC125MEL use, and is it RoHS-compliant?

The MC74VHC125MEL uses a 14-lead SOIC EIAJ package (Case 965, M suffix), measuring 10.2 mm × 5.3 mm with 1.27 mm lead pitch. It is Pb-free and RoHS-compliant per Directive 2011/65/EU, with no lead content in die attach, bond wires, or terminal finish. The "M" suffix explicitly denotes this EIAJ-compliant, lead-free variant per ON Semiconductor's ordering information.

Can MC74VHC125MEL operate reliably at –55°C?

Yes, the MC74VHC125MEL is specified for full operation from –55°C to +125°C across all recommended conditions (VCC = 2.0–5.5 V). Its AC and DC parameters - including propagation delay, output drive, and noise immunity - are guaranteed over this extended industrial temperature range, as confirmed in the Recommended Operating Conditions and Electrical Characteristics tables of the datasheet.

How does MC74VHC125MEL handle unused inputs and outputs?

Unused inputs on the MC74VHC125MEL must be tied to a valid logic level - either VCC or GND - to prevent floating nodes that could cause excessive ICC or oscillation. Unused outputs may be left open (high-impedance) but must not be shorted or pulled externally while enabled. This guidance is explicitly stated in the datasheet's "Precautions" section and applies to all four A and OE inputs and Y outputs.