What is a ZnO Varistor? Main Application Scenarios?

Zinc Oxide Varistor (ZNO Varistor) is a semiconductor material composed of zinc oxide (ZnO) mixed with various metal oxides. Its working principle is based on its semiconductor characteristics, where physical phenomena such as impurity ions, defects, and lattice distortions in the material cause changes in the number of free electrons, leading to variations in resistance under external forces.

Specifically, when an external force acts on the ZNO varistor, lattice distortions within its structure alter the local charge density, thereby increasing or decreasing the number of free electrons in the material. This, in turn, affects current flow and resistance, ultimately manifesting as a characteristic decrease in resistance with increasing external force.

ZNO varistors feature high sensitivity, fast response times, and good stability, making them widely used in electronic circuits for applications such as voltage protection, overcurrent protection, and temperature compensation.

Common application scenarios include:

1. Power Supply Protection: Used as an overvoltage protection device in power circuits to prevent damage from excessive voltage.
2. Signal Protection: Employed as an overvoltage protection device in signal lines to safeguard signal processing components from damage caused by excessive voltage.
3. Temperature Compensation: Utilized as a component in temperature compensation circuits for temperature sensors to improve accuracy and stability.
4. Internal Resistance Measurement: Applied in charging and discharging circuits to measure the internal resistance of batteries, ensuring their normal operation.

In summary, ZNO varistors are essential resistive components that play an irreplaceable role in electronic circuits.