High-voltage ceramic capacitor function

In many electronic products, high voltage ceramic capacitors are used. What is a high voltage ceramic capacitor, what function?

High-voltage ceramic capacitors are wafer-shaped capacitors made of ceramic materials. The outer casing is ceramic and used for insulation. A major feature of high-voltage ceramic capacitors is their high withstand voltage, which is typically greater than 1KV. High voltage ceramic capacitors are conventionally available in 2KV, 3KV, and 4KV voltages. Often used in high pressure applications. Up to 30KV.

The high-voltage ceramic capacitor has the characteristics of wear-resistant DC high voltage, and is suitable for high-voltage bypass and coupling circuits. The low-loss high-voltage wafer has low dielectric loss, and is particularly suitable for use in circuits such as television receivers and scanning.

There are three main functions of high voltage ceramic capacitors:

1. The capacity loss has high stability with temperature frequency;

2. The special series structure is suitable for high voltage and long-term operational reliability;

3. High current climb rate and suitable for high current loop non-inductive structures. It is commonly used in high-stability oscillation circuits as loops, bypass capacitors, and pad capacitors to eliminate high-frequency interference.

Ceramic chip capacitors are not suitable for use in pulse circuits because they are susceptible to breakdown by pulse voltages.

Ceramic tiles have class I porcelain, class II porcelain, class III porcelain, class I porcelain, NP0, temperature characteristics, frequency characteristics and voltage characteristics are good, because the dielectric constant is not high, so the capacity is not large; II porcelain Secondly, X7R has better temperature characteristics and voltage characteristics; Class III porcelain has a high dielectric constant, so the capacity can be made very large, but the temperature characteristics and voltage characteristics are not so good. Ceramic capacitors are generally small in size. In addition, an important feature is emphasized: after the dielectric capacitor is broken down, it is often short-circuited, which is its weakness. After the film capacitor fails, it is generally open.

The function of high-voltage ceramic capacitors is mainly three aspects. The capacity loss has high stability with temperature and frequency; the special series structure is suitable for high-voltage and long-term operational reliability; the high current climbing rate is suitable for high-current loop non-inductive structure. Ceramic capacitors should not be used in pulse circuits because they are susceptible to breakdown by pulse voltages.