Metal Oxide Varistor 14D391K MOV

Metal Oxide Varistor 14D391K MOV

The 14D391K is a passive electronic component that serves as a voltage-clamping device, designed to protect circuits from sudden and destructive over-voltage transients. Its core operational principle is based on a highly non-linear voltage-current characteristic. Under standard operating conditions with normal voltage levels, it maintains an extremely high electrical resistance, drawing negligible current. However, when the voltage across its terminals exceeds a specific threshold, its molecular structure allows it to become highly conductive almost instantaneously.

This varistor is built around a ceramic bulk material primarily composed of zinc oxide grains interspersed with minor amounts of other metal oxides. The intricate boundaries between these grains create a dense network of semiconductor junctions, which are the fundamental elements responsible for the voltage-dependent switching behavior. This ceramic element is then robustly encapsulated in a flame-retardant epoxy resin, which provides essential mechanical protection, electrical insulation, and environmental sealing.

The primary role of the 14D391K is to act as a sacrificial safeguard by shunting excessive surge current away from sensitive and costly components. When a voltage spike occurs, it rapidly clamps the voltage to a safer, predetermined level, thereby limiting the potential that reaches downstream circuitry. It performs this function by absorbing the energy from the transient event and dissipating it internally as heat, thus preserving the integrity of the main electronic system.

Features:

• Fast response to transient over-voltage events.
• Large transient energy absorption capability.
• Low clamping ratio for effective voltage limitation.
• No follow-on current after the surge subsides.
• Flame-retardant epoxy resin coating (UL94 V-0).
• Meets Moisture Sensitivity Level (MSL) 1.
• Safety certifications from UL, CUL, and TÜV.

Specifications:

Pinout Diagram:

Footprint Diagram:

Applications:

• Surge Protection in Electronic Home Appliances.
• Surge Protection in Gas and Petroleum Appliances.
• Surge Protection in Industrial Electronics.
• Surge Protection in Consumer Electronics.
• Transistor, Diode, and IC Semiconductor Protection.
• Thyristor or Triac Semiconductor Protection.
• Relay and Electromagnetic Valve Surge Absorption.

Package Contents:

• 1x Metal Oxide Varistor 14D391K MOV

Datasheet