As the weather gets colder, the air becomes drier, making winter a season prone to static electricity. Common phenomena such as crackling static during clothing changes, hair sticking to clothes due to friction, or being shocked by a doorknob are examples of electrostatic discharge (ESD). ESD occurs when two different materials come into contact or friction is generated between them.
In modern electronic device protection mechanisms, ESD is a threat that cannot be ignored. ESD can disrupt the operation of electronic products and equipment, potentially causing malfunctions or even permanent damage to components.
Not only can ESD directly damage electronic components, but it can also degrade their performance over time through cumulative effects, leading to unexpected failures.
Thus, implementing appropriate ESD protection is essential, and varistors play a crucial role in this process.
What Is a Varistor?
A varistor is a component whose resistance value changes sharply with an increase in voltage at a given temperature. Made from semiconductor materials—primarily zinc oxide combined with various metal oxides—it is manufactured through forming, sintering, surface treatment, and other processes.
Thanks to its material composition and manufacturing process, a varistor exhibits nonlinear voltage-current characteristics, enabling it to alter its resistance in response to voltage changes. This makes it widely used in the protection circuits of electronic devices.
How Does a Varistor Enhance ESD Protection?
1. Parallel Connection in Circuits
Varistors are typically connected in parallel across the circuit that requires protection. When an ESD event occurs, the varistor responds quickly and absorbs the excess voltage, thereby protecting other components in the circuit from damage.
2. Choosing High Energy-Tolerance Varistors
The larger the varistor’s energy tolerance, the higher the surge current it can withstand. By acting as a suppressor, the varistor safeguards devices and circuits against ESD events or transient overvoltages caused by accumulated surges.
3. Using Varistors with Other Protection Components
In practical applications, varistors can be used in conjunction with other protection components, such as TVS diodes or ESD suppression diodes. This combination enhances the absorption and dispersion of overvoltage, further improving the circuit’s ESD resistance.
Conclusion
ESD is a significant cause of electronic product malfunctions and damage. As a protective device, the varistor plays a critical role in ESD prevention.
Dongguan Zhixu Electronics (also JYH HSU, short for JEC) offers a comprehensive range of varistor models with guaranteed quality and reliable after-sales support. Our products are certified under the ISO9001:2015 quality management system, and we provide a full range of safety-certified components, including safety capacitors (X and Y capacitors), varistors, ceramic capacitors, film capacitors, and supercapacitors that meet low-carbon standards.
Post time: Dec-16-2024