STMicroelectronics 74LCX14MTR

Overview

74LCX14MTR from STMicroelectronics is a low-voltage CMOS hex Schmitt-trigger inverter with 5V-tolerant inputs, designed for noise-immune signal conditioning in 3.3V systems interfacing to 5V logic. It delivers t_PD ≤ 5.0 ns at V_CC = 3.0 V, symmetrical ±24 mA output drive, and 0.8 V typical hysteresis-enabling reliable reception of slow-rising signals in industrial bus receivers.

For engineers reviewing the 74LCX14MTR datasheet, 74LCX14MTR pinout, 74LCX14MTR application, or 74LCX14MTR equivalent, this device is selected for robust input threshold separation, rail-to-rail 5V-tolerant input operation, high-speed 3.3V logic compatibility, and SO-14 package suitability in space-constrained board layouts.

Technical Context

The 74LCX14 implements six independent Schmitt-trigger inverters using sub-micron C2MOS technology, with VT+ = 1.2–2.2 V and VT− = 0.6–1.5 V at V_CC = 3.0 V, yielding 0.4–1.2 V hysteresis. Its input structure supports 5.5 V DC tolerance regardless of V_CC, enabling safe connection to legacy 5V buses without level shifters.

All outputs feature matched |I_OH| = I_OL ≥ 24 mA at V_CC = 3.0–3.6 V and balanced t_PLH ≅ t_PHL, ensuring minimal duty-cycle distortion in clocked or data-line applications. Power-down leakage (I_OFF) remains ≤10 µA when V_CC = 0 V and inputs/outputs biased to 5.5 V.

Key Specifications

Pinout & Package

74LCX14MTR is housed in a 14-pin SOIC (SO-14) package per JEDEC MS-012, with 1.27 mm pitch, 8.55–8.75 mm body length, and ECOPACK® lead-free finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC14APWR and MC74LCX14DT, the 74LCX14MTR offers superior noise immunity for marginal-edge signals due to its wider hysteresis, while maintaining identical pinout and SO-14 compatibility-making it optimal for industrial sensor and legacy bus interface roles where edge fidelity matters more than raw drive strength or size.

Availability

74LCX14MTR is available at Aetrix Electronics and suitable for industrial sensor interfaces, 3.3V/5V mixed-voltage bus receivers, and PCI-compliant peripheral logic requiring stable component supply across extended temperature ranges (–40°C to +85°C).

Supply support for 74LCX14MTR 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 automotive, industrial, and power management ICs with strong emphasis on reliability and eco-design.

The 74LCX logic family was engineered for low-voltage, high-speed interoperability between 3.3V systems and 5V legacy infrastructure-targeting cost-sensitive industrial controls and communications equipment.

FAQ

Can 74LCX14MTR operate with V_CC = 2.0 V and still meet 5V input tolerance?

Yes. The datasheet guarantees VI = 0–5.5 V operation across the full V_CC range of 2.0–3.6 V. At V_CC = 2.0 V, input protection diodes remain active and clamp-free up to 5.5 V, verified by absolute maximum ratings and input leakage tests showing II ≤ ±5 µA at VI = 5.5 V.

Is the 74LCX14MTR pinout compatible with standard 74HC14 or 74LS14?

Yes-pin-for-pin and functionally compatible with 74-series hex Schmitt inverters including 74HC14 and 74LS14. All six inverter channels, GND (pin 7), and V_CC (pin 14) occupy identical positions; however, 74LCX14MTR requires no pull-up resistors and operates natively at 3.3V with 5V-tolerant inputs.

What is the maximum capacitive load this device can drive while maintaining 5.0 ns t_PD?

The 5.0 ns t_PD (max) is specified at CL = 50 pF, RL = 500 Ω, and V_CC = 3.0 V. Driving loads >50 pF increases propagation delay linearly-e.g., at CL = 100 pF, measured t_PD rises to ~7.2 ns. For >50 pF, add series termination or reduce trace length to maintain timing margins.

Does 74LCX14MTR support hot insertion when V_CC is unpowered?

Yes. With V_CC = 0 V, the device exhibits I_OFF ≤10 µA when any input or output is biased to 5.5 V, and latch-up immunity exceeds 500 mA per JESD17. This enables safe hot-plug operation in backplane or modular systems where power sequencing is uncontrolled.