STMicroelectronics M74HC14B1R

Overview

M74HC14B1R from STMicroelectronics is a high-speed CMOS hex Schmitt trigger inverter in 14-pin DIP package, featuring 2V–6V operation, 12ns typical propagation delay at 6V, 1µA max quiescent current at 25°C, and 20% V_CC input hysteresis. It serves as a noise-immune signal conditioner for slow-rising clock or sensor inputs in industrial control interfaces.

For engineers reviewing the M74HC14B1R datasheet, M74HC14B1R pinout, M74HC14B1R application, or M74HC14B1R equivalent, key selection criteria include hysteresis voltage (0.54–1.7V), symmetrical output drive (±4mA min), wide temperature range (–55°C to +125°C), and DIP-14 mechanical compatibility with legacy 74-series layouts.

Technical Context

The M74HC14B1R implements six independent Schmitt-trigger inverters using silicon gate C2MOS technology, each with fixed hysteresis thresholds (V_t+/V_t−) defined as percentages of V_CC. Its input protection includes ESD and transient voltage clamping circuits.

Propagation delays are balanced (t_PLH ≅ t_PHL), and output impedance is symmetrical (|I_OH| = I_OL ≥ 4mA), enabling clean waveform shaping of slow or noisy digital signals without external components.

Key Specifications

Pinout & Package

Package: Plastic Dual In-line Package (DIP-14), 0.3" wide, through-hole mount, JEDEC MS-001 compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC14N and 74LVC14APW, M74HC14B1R uniquely combines extended temperature operation, DIP-14 through-hole compatibility, and ultra-low quiescent current - making it optimal for legacy-replacement and harsh-environment signal conditioning where footprint and power matter.

Availability

M74HC14B1R is available at Aetrix Electronics and suitable for industrial sensor interfaces, motor control feedback paths, automotive wake-up detection, and legacy system clock conditioning requiring stable component supply and long-term obsolescence management.

Supply support for M74HC14B1R 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, designing and manufacturing microcontrollers, power ICs, sensors, and analog/mixed-signal devices for industrial, automotive, and consumer markets.

The M74HC14 belongs to ST's high-speed CMOS logic family, engineered specifically for noise-immune digital interfacing in electrically hostile environments where signal integrity cannot be compromised.

FAQ

Is M74HC14B1R compatible with 5V TTL logic levels?

Yes - at V_CC = 5V, its VOH is ≥4.4V and VOL is ≤0.26V under 4mA load, meeting TTL output swing requirements. Inputs accept TTL-high (≥2.0V) and TTL-low (≤0.8V) thresholds within hysteresis margins, ensuring interoperability without level shifters.

Can M74HC14B1R operate reliably at 2.0V supply?

Yes - it is fully specified down to 2.0V, with guaranteed V_t+ = 1.0V (min), V_t− = 0.3V (max), and propagation delay ≤190ns over –55°C to +125°C. This makes it suitable for single-cell Li-ion or 2xAA battery-powered systems.

What is the maximum capacitive load this device can drive?

Driving CL = 50pF is validated in AC specs (t_PLH/t_PHL measured at CL = 50pF). With symmetrical 4mA output drive, it can reliably drive up to ~100pF while maintaining <25ns additional delay - verified via typical CPD = 28pF and ICC(opr) modeling.

Does M74HC14B1R require external pull-up or pull-down resistors on unused inputs?

No - all six inputs have internal protection diodes and defined hysteresis thresholds. However, floating inputs must be avoided: unused channels should be tied to V_CC or GND to prevent increased ICC and potential oscillation due to noise coupling into high-impedance Schmitt inputs.