onsemi MC74VHC125D

Overview

MC74VHC125D from onsemi is a quad 3-state bus buffer IC designed for high-speed, low-power bidirectional data routing in 2 V–5.5 V digital systems. It features four independent A→Y buffers with active-high output enables (OE1–OE4), 3.8 ns typical propagation delay at 5 V, ±25 mA output drive, and CMOS-input/CMOS-output compatibility enabling 3.3 V ↔ 5 V level translation.

For engineers reviewing the MC74VHC125D datasheet, pinout, applications, or equivalent options, this device is selected for bus isolation, memory address/data gating, and mixed-voltage interface design where low quiescent current (4 µA max), high noise immunity (28% VCC), and AEC-Q100 qualified variants are critical.

Technical Context

The MC74VHC125D implements four identical non-inverting buffer stages, each with a dedicated active-high 3-state control input (OE). Its silicon-gate CMOS architecture delivers TTL-compatible speed with CMOS power efficiency, and input structures tolerate up to 5.5 V - enabling safe interfacing between 3 V and 5 V domains without external level shifters.

All outputs exhibit balanced rise/fall times, low dynamic noise (VOLP ≤ 0.8 V), and latchup immunity exceeding 100 mA. The device operates across −55°C to +125°C and supports hot insertion due to power-down protection on inputs and robust ESD performance (>2000 V HBM).

Key Specifications

Pinout & Package

TSSOP-14 package (Case 948G), 4.9 mm × 4.4 mm × 1.2 mm body, lead pitch 0.65 mm, Pb-free, RoHS compliant, moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC125APWR and MC74VHCT125ADTR2G, the MC74VHC125D uniquely supports both 3.3 V and 5 V input logic thresholds while delivering full 5 V output swing - making it the only option among the three for reliable 3.3 V ↔ 5 V bidirectional level translation without external components.

Availability

MC74VHC125D is available at Aetrix Electronics and suitable for industrial automation, automotive electronics, and medical instrumentation requiring stable component supply, long-term lifecycle support, and AEC-Q100-compliant variants.

Supply support for MC74VHC125D 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, logic, and sensing solutions for automotive, industrial, and cloud infrastructure markets.

The MC74VHC125D belongs to the VHC (Very High Speed CMOS) logic family, engineered for high-speed digital interface applications demanding low power, wide supply range, and robust noise immunity in harsh environments.

FAQ

What is the maximum operating temperature for the MC74VHC125D?

The MC74VHC125D is rated for operation from −55°C to +125°C per its Recommended Operating Conditions table. This extended range supports deployment in under-hood automotive, industrial motor drives, and outdoor telecom equipment where ambient temperatures exceed standard commercial limits. The MC74VHC125D maintains specified timing and DC parameters across this full range.

Does the MC74VHC125D support 3.3 V input logic levels when powered at 5 V?

Yes - the MC74VHC125D inputs are fully CMOS-compatible and accept logic-high inputs as low as 1.5 V at V_CC = 2.0 V, scaling to 3.85 V at V_CC = 5.5 V. When powered at 5 V, a 3.3 V logic-high signal exceeds the minimum VIH of 3.15 V (typ), ensuring reliable recognition. This enables direct interfacing between 3.3 V microcontrollers and 5 V buses using the MC74VHC125D.

Can the MC74VHC125D be used as a level shifter between 3.3 V and 5 V systems?

Yes - the MC74VHC125D is explicitly designed for this function. Its inputs tolerate up to 5.5 V and recognize 3.3 V as a valid logic-high when V_CC = 5 V, while its outputs swing rail-to-rail (0 V to 5 V). This allows bidirectional level translation: 3.3 V logic drives the A input, and the Y output drives a 5 V load - all within a single, compact TSSOP-14 package.

What is the purpose of the "−Q" suffix in MC74VHC125DTR2G−Q*?

The "−Q" suffix denotes an AEC-Q100 qualified version of the MC74VHC125D, manufactured under automotive-specific process controls and test flows. The MC74VHC125DTR2G−Q* variant undergoes additional stress testing, lot traceability, and PPAP documentation to meet automotive quality and reliability requirements for body electronics, infotainment, and ADAS subsystems.

How does the MC74VHC125D handle unused inputs and outputs?

Per the datasheet's Recommended Operating Conditions (Note 5), unused inputs must be tied to a defined logic level - either V_CC or GND - to prevent floating states that increase power consumption and risk oscillation. Unused outputs may be left open (high-impedance) but must not be shorted or driven externally while their OE is active; tri-stating them via OE is preferred for safety and noise reduction in the MC74VHC125D.