Texas Instruments SN74HC14DR

Overview

SN74HC14DR from Texas Instruments is a hex inverter IC with Schmitt-trigger inputs, designed for noise-immune digital signal conditioning in 2V–6V logic systems. It delivers six independent inverters (Y = A), each with hysteresis (ΔVT ≥ 0.4 V at 4.5 V), propagation delay ≤26 ns (6 V), and output drive capability of ±4 mA - enabling reliable switch debouncing, clock synchronization, and signal inversion in industrial control and embedded interfaces.

For engineers reviewing the SN74HC14DR datasheet, SN74HC14DR pinout, SN74HC14DR application, or SN74HC14DR equivalent, this page provides verified technical context, real-world design meaning for key specs, validated pin functions for SOIC-14, confirmed alternatives with functional trade-offs, and supply support for volume production and long-term BOM continuity.

Technical Context

The SN74HC14DR implements six identical CMOS inverters, each featuring Schmitt-trigger input architecture that provides defined hysteresis (VT+ and VT− differ by ≥0.4 V at 4.5 V) to reject slow-rising or noisy signals. Its balanced push-pull outputs source/sink up to 4 mA while maintaining VOH ≥3.98 V and VOL ≤0.26 V under load.

It operates across −40°C to +85°C with supply voltage flexibility (2 V–6 V), supports fanout of 10 LSTTL loads, and exhibits low ICC (≤20 µA at 6 V), making it suitable for mixed-voltage interfacing and low-power edge-sensing applications without external hysteresis components.

Key Specifications

Pinout & Package

SN74HC14DR is supplied in a 14-pin SOIC (D) package measuring 8.65 mm × 6.0 mm (body: 8.65 mm × 3.9 mm), RoHS-compliant, with standard surface-mount footprint and moisture sensitivity level (MSL) 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC14DR, SN74HCS14DR trades speed for sub-µA quiescent current, while MC74HC14ADTR2G maintains identical functionality in a smaller package at the cost of reduced thermal performance - both require validation of timing margins and board-level thermal design before substitution.

Availability

SN74HC14DR is available at Aetrix Electronics and suitable for industrial control panels, embedded sensor interfaces, and programmable logic peripheral conditioning requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for SN74HC14DR 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic solutions, with decades of heritage in industry-standard logic families including the 74HC series.

The SN74HC14DR belongs to TI's 74HC high-speed CMOS logic product line, engineered for robust noise immunity and broad supply compatibility in industrial, automotive, and communications infrastructure applications.

FAQ

What is the maximum capacitive load SN74HC14DR can drive while meeting datasheet timing specs?

The SN74HC14DR is characterized for optimal performance with capacitive loads ≤70 pF, as specified in the Application and Implementation section. Driving larger loads increases propagation delay and transition time - for example, a 100 pF load raises tpd beyond the 26 ns max at 6 V. To maintain timing compliance, use series resistors or buffer stages when interfacing with heavier loads. The SN74HC14DR datasheet explicitly recommends limiting CL to 70 pF for guaranteed spec adherence.

Can SN74HC14DR operate reliably at 2.5 V supply voltage?

Yes, SN74HC14DR is fully specified from 2 V to 6 V, including 2.5 V. At 2.5 V, its hysteresis is ≥0.2 V, VOH ≥2.4 V, VOL ≤0.1 V, and tpd ≤155 ns - all within Recommended Operating Conditions. This makes SN74HC14DR suitable for mixed-voltage systems such as battery-powered IoT nodes interfacing 2.5 V sensors to 3.3 V processors. No derating or external components are required for 2.5 V operation.

How should unused inputs on SN74HC14DR be handled?

Unused inputs on SN74HC14DR must be terminated to either VCC or GND - never left floating - to prevent undefined logic states, increased ICC, and potential oscillation. A 10-kΩ pull-up or pull-down resistor is recommended for flexibility; direct connection is acceptable for permanently unused channels. This requirement is explicitly stated in Section 8.2.1.2 of the SN74HC14DR datasheet and applies regardless of whether the input is Schmitt-triggered.

Does SN74HC14DR support hot-swap or live-insertion?

No, SN74HC14DR does not support hot-swap. Its Absolute Maximum Ratings specify that VCC must be established before applying input signals, and VI must remain within 0 V to VCC at all times. Violating this (e.g., applying input before VCC ramps) risks latch-up or permanent damage due to internal clamp diode conduction. System-level hot-swap protection requires external circuitry - the SN74HC14DR itself has no built-in sequencing or fault protection.

Is SN74HC14DR pin-compatible with SN74LS14?

No, SN74HC14DR is not pin-compatible with SN74LS14. While both are hex Schmitt-trigger inverters in 14-pin packages, SN74LS14 uses bipolar TTL technology with different DC characteristics (e.g., input current requirements, VIL/VIH thresholds) and lacks CMOS-level supply flexibility. Physical pinout matches (1A–1Y–2A–2Y…–VCC–GND), but direct replacement risks incorrect logic interpretation, excessive loading, or damage due to mismatched input structure - SN74HC14DR requires no input current, unlike SN74LS14's 0.8 mA sink requirement.