A semiconductor component is an electronic component whose conductivity is between a good conductor and an insulator. It uses the special electrical properties of semiconductor materials to complete specific functions. It can be used to generate, control, receive, transform, amplify signals and perform energy conversion. Zener diodes and varistors are both semiconductor components.
This article will discuss the respective roles of Zener diodes and varistors in the circuit.
Zener Diode
Zener diode is a crystal diode made of silicon material, which belongs to semiconductor components, and its resistance is very high until the critical reverse breakdown voltage.
When the reverse voltage is lower than the reverse breakdown voltage, the reverse resistance is large and the reverse leakage current is extremely small. When the reverse voltage of the Zener diode in the circuit is close to the critical value of the reverse voltage, the reverse current suddenly increases, which is called breakdown. At this critical breakdown point, the reverse resistance drops suddenly.
The zener diode in the circuit breaks down in reverse, and when the current changes in a wide range, the voltage across the zener diode remains basically unchanged, showing a voltage stabilizing characteristic. Therefore, Zener diodes are widely used in regulated power supplies, and are mainly used as voltage stabilizers or voltage reference components in circuits.
Varistor
Varistor is a new type of voltage-limiting protection device. Its resistance material is made of semiconductor materials. It belongs to semiconductor components and has nonlinear volt-ampere characteristics. Its resistance value is sensitive to voltage. The resistance of the resistor changes with the voltage.
When overvoltage occurs in the circuit, the varistor clamps the voltage to a relatively fixed voltage value when the current passes through the varistor, and absorbs excess current to protect the subsequent circuit and other electronic components.
Varistors play a role in suppressing transient overvoltage and lightning protection in circuits, and are used in surge suppressors, security systems, motor protection, automotive electronic systems, household appliances, consumer electronics, etc.
JYH HSU(JEC) Electronics Ltd (or Dongguan Zhixu Electronic Co., Ltd.) is an electronic components manufacturer whose factories are ISO 9000 and ISO 14000 certified. Welcome to contact us if you need capacitors or resistors.
Post time: Apr-06-2023