onsemi MC74VHCT14AMG

Overview

MC74VHCT14AMG from onsemi is a hex Schmitt-trigger inverter IC operating at 4.5–5.5 V supply, with 8 mA output drive, 7 ns typical propagation delay at 5 V, and TTL-compatible input thresholds. It performs signal conditioning and noise-immune digital inversion in microcontroller I/O expansion and sensor interface circuits.

For engineers reviewing the MC74VHCT14AMG datasheet, pinout, applications, or equivalent options, key selection criteria include input hysteresis width (≈0.8 V), rail-to-rail output swing, industrial temperature range (−40°C to +85°C), and SOIC-14 package compatibility with legacy 74-series logic layouts.

Technical Context

This device implements six independent CMOS Schmitt-trigger inverters using silicon-gate VHCT technology, ensuring TTL-level input recognition while maintaining CMOS power efficiency. Each gate features hysteresis of 0.5 V (min) to 1.0 V (max) for robust noise rejection on slow or noisy signals.

The MC74VHCT14AMG operates strictly within 4.5–5.5 V V_CC, supports fan-out of 10 LSTTL loads per output, and guarantees AC/DC parametric performance across the full industrial temperature range without derating.

Key Specifications

Pinout & Package

MC74VHCT14AMG is housed in a 14-pin Small Outline Integrated Circuit (SOIC-14) package with 1.27 mm pitch, JEDEC MS-012AC compliant, and rated for surface-mount reflow assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar hex Schmitt-trigger inverter applications.

Compared with SN74LV14APWR and 74HC14D,653, the MC74VHCT14AMG uniquely delivers TTL-compatible inputs, 7 ns speed at 5 V, and industrial temperature rating in SOIC-14-making it the optimal choice for upgrading legacy 74LS14-based systems without layout or firmware changes.

Availability

MC74VHCT14AMG is available at Aetrix Electronics and suitable for industrial automation, sensor interface, and legacy system retrofit applications requiring stable component supply and long-term lifecycle support.

Supply support for MC74VHCT14AMG 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 is a global semiconductor leader delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

The VHCT logic family-including MC74VHCT14AMG-is engineered for seamless TTL-to-CMOS migration in industrial and infrastructure systems, emphasizing pin compatibility, timing predictability, and extended temperature operation.

FAQ

What is the recommended operating voltage range for the MC74VHCT14AMG?

The MC74VHCT14AMG is specified to operate reliably between 4.5 V and 5.5 V. Operation outside this range may result in undefined logic states or degraded noise immunity. The device is not rated for 3.3 V operation, and its TTL-compatible inputs require minimum VIH of 2.0 V-ensuring compatibility only with 5 V logic families. Always use local 0.1 µF ceramic decoupling at V_CC pin 14 for stable performance.

Does the MC74VHCT14AMG support true TTL input levels?

Yes, the MC74VHCT14AMG features TTL-compatible input thresholds: VIL ≤ 0.8 V (max) and VIH ≥ 2.0 V (min) at V_CC = 5.0 V. This allows direct connection to legacy 74LS and 74ALS outputs without level translation. Unlike standard 74HC devices, the VHCT variant maintains these thresholds across temperature and supply variations-critical for field-replaceable industrial modules where signal integrity must be guaranteed.

Can the MC74VHCT14AMG be used as a hardware debouncer for mechanical switches?

Yes, the MC74VHCT14AMG is widely deployed for hardware debouncing due to its built-in Schmitt-trigger hysteresis (0.5–1.0 V). When a switch closes, the input transitions cleanly through the hysteresis band, producing a single, glitch-free output edge. This eliminates the need for RC filters or firmware polling loops. For optimal results, connect the switch between V_CC and an input pin with a 10 kΩ pull-down resistor-then route the corresponding output to an MCU interrupt pin.

Is the MC74VHCT14AMG pin-compatible with the obsolete 74LS14?

Yes, the MC74VHCT14AMG uses the same SOIC-14 package and identical pinout as the 74LS14, including input/output pairing and power/ground locations. Electrical characteristics-including propagation delay (7 ns vs. 15 ns for LS), output drive (±8 mA vs. ±0.4 mA for LS), and input thresholds-are improved while preserving functional equivalence. This makes MC74VHCT14AMG a direct drop-in upgrade for boards originally designed for 74LS14.

What is the maximum capacitive load the MC74VHCT14AMG can drive without exceeding propagation delay specs?

The MC74VHCT14AMG is characterized up to 50 pF load capacitance in its datasheet. At 5 V supply and 25°C, t_pd remains ≤7 ns with ≤30 pF; beyond 50 pF, delay increases nonlinearly and output rise/fall times degrade. For loads >30 pF, add series termination (e.g., 33 Ω) near the driver to suppress ringing. Avoid driving long traces or multiple parallel inputs without verifying timing margins in the target application.