A film capacitor is made by using metal foil as the electrode plates and plastic film as the dielectric. The capacitor is formed by winding or stacking the films to overlap at both ends, creating a cylindrical structure.
As a fundamental component in electronic products, film capacitors offer several advantages, such as a wide operating temperature range, self-healing capabilities, high voltage resistance, and good frequency characteristics. These properties make them ideal for applications in new energy, lighting, solar, and wind energy sectors.
Just as smartphones come in different series and models, film capacitors are categorized based on the dielectric material used. The main types are polyester film capacitors, polypropylene film capacitors, polystyrene film capacitors, and polycarbonate film capacitors.
So, what are the advantages of different dielectric materials used in film capacitors?
1. Polyester Film Capacitors
Polyester film capacitors are made by using metalized polyester film as the dielectric and metal foil as the electrode. These capacitors are wound into a cylindrical shape and sealed with epoxy resin.
· Advantages: Wide operating temperature range, good heat resistance, high dielectric constant, stable capacitance, excellent electrical performance, high insulation resistance, and self-healing properties.
· Applications: These capacitors are suitable for instruments, household appliances, AC and DC circuits, and audio system crossover circuits.
2. Polypropylene Film Capacitors
Polypropylene film capacitors use polypropylene film as the dielectric and aluminum foil as the electrode. These are wound with a non-inductive structure and encapsulated with epoxy resin.
· Advantages: Excellent electrical performance, high reliability, high-temperature resistance, wide capacitance range, small size, self-healing properties, and long service life.
· Applications: Suitable for televisions, computer monitors, communication equipment, and other consumer electronics.
3. Polystyrene Film Capacitors
Polystyrene film capacitors use polystyrene plastic film as the dielectric and metal foil or metallized layer as the electrode.
· Advantages: Excellent electrical performance, very low dielectric loss, high quality factor, and almost no change in capacitance with voltage, frequency, or temperature.
· Applications: These capacitors are ideal for high-fidelity audio systems, precision measurement instruments, RC oscillators, and analog filters.
4. Polycarbonate Film Capacitors
Polycarbonate film capacitors use polycarbonate film as the dielectric.
· Advantages: Good operating temperature range, excellent stability, strong flame resistance, and minimal changes in dielectric performance.
· Applications: Commonly used in automotive electronics, industrial control, and other demanding applications.
Choosing the Right Capacitor
Each type of film capacitor has unique characteristics suited for specific applications. When selecting capacitors for your electronic circuits, it’s crucial to choose the correct type to avoid potential issues.
This article is provided by JYH HSU (JEC) Electronics. JEC is a research, development, production, and sales-oriented company specializing in manufacturing and selling various electronic components such as capacitors and resistors.
Post time: Nov-07-2025