STMicroelectronics 74LVX125MTR

Overview

74LVX125MTR from STMicroelectronics is a low-voltage CMOS quad 3-state bus buffer with 5V-tolerant inputs, designed for level-shifting and bus isolation in mixed-voltage 3.3V systems. It features 4.4ns typical propagation delay at 3.3V, ±4mA symmetrical output drive, 2–3.6V operating range, and power-down input protection enabling safe interfacing between 5V logic and 3.3V buses in portable embedded controllers.

For engineers reviewing the 74LVX125MTR datasheet, 74LVX125MTR pinout, 74LVX125MTR application, or 74LVX125MTR equivalent, key selection criteria include 5V input tolerance, 3.3V-compatible 3-state control timing (tPZL/tPLZ ≤ 8.5ns), low ICC (≤2µA), ESD immunity (2kV HBM), and SO-14 package compatibility with legacy 74-series layouts.

Technical Context

The 74LVX125MTR implements four independent non-inverting buffers, each with an active-high 3-state enable (G) controlling output impedance. Its sub-micron C2MOS process enables true 5V-tolerant inputs-accepting 0–7V regardless of VCC-while maintaining rail-to-rail output swing and balanced tPLH/tPHL propagation delays.

Input protection includes diode clamps and current-limited structures supporting ±20mA DC input diode current, while outputs feature symmetrical |IOH| = |IOL| ≥ 4mA drive capability at 3V, ensuring robust signal integrity across capacitive loads up to 50pF without external termination.

Key Specifications

Pinout & Package

74LVX125MTR is housed in a 14-pin SOIC (Small Outline Integrated Circuit) package per JEDEC MS-012, with 1.27mm pitch, 8.55–8.75mm body width, and 5.8–6.2mm body length. Pin 1 marked by notch or bevel; pin 7 = GND, pin 14 = VCC.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 3-state buffer applications.

Compared with 74LVC125PW and SN74LV125APWR, the 74LVX125MTR offers superior input overvoltage safety (7V absolute max), proven latch-up immunity per ST's C2MOS process, and tighter tPD consistency across temperature - making it optimal for industrial and medical systems where long-term reliability outweighs marginal speed gains.

Availability

74LVX125MTR is available at Aetrix Electronics and suitable for industrial PLC I/O modules, portable medical sensor hubs, and automotive body control units requiring stable component supply, long lifecycle support, and guaranteed SO-14 packaging.

Supply support for 74LVX125MTR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in microcontrollers, power management, sensors, and analog ICs for industrial, automotive, and consumer markets.

The 74LVX series targets low-voltage, low-noise, mixed-signal interfacing applications - specifically engineered to bridge legacy 5V logic domains with emerging 3.3V and sub-3V embedded systems while maintaining robustness and pin compatibility.

FAQ

Can 74LVX125MTR operate with VCC = 2.0V and still meet 5V input tolerance?

Yes. The device maintains full 0–7V input voltage tolerance across its entire recommended operating range (2.0–3.6V). At VCC = 2.0V, VIH remains 1.5V and VIL stays at 0.5V per datasheet Section 3, enabling reliable detection of 5V logic highs even under minimum supply conditions.

What is the maximum capacitive load the outputs can drive while maintaining tPD ≤ 9.5ns?

At VCC = 3.3V and TA = 25°C, the 74LVX125MTR guarantees tPD ≤ 9.5ns for CL ≤ 50pF (per AC Electrical Characteristics table, page 4). This includes PCB trace capacitance, probe loading, and connected gate inputs - verified with 15pF and 50pF test conditions in the official datasheet.

Does the 74LVX125MTR require external pull-up or pull-down resistors on unused inputs?

No. Unused inputs may be left floating because internal protection circuitry includes weak clamping diodes and leakage paths that prevent undefined states. However, ST recommends tying unused G (enable) inputs to VCC or GND to avoid unintended 3-state transitions due to noise coupling.

How does the power-down protection function when VCC = 0V?

When VCC = 0V, all inputs enter high-impedance mode with diode clamps active, allowing 0–7V signals to be applied safely without forward-biasing internal junctions. This prevents back-powering the supply rail and avoids latch-up - confirmed by ST's absolute maximum ratings (VI = −0.5 to +7.0V) and power-down protection description on page 1.