Ceramic capacitor

Low-voltage ceramic capacitors:

 

Production principle:

A high-dielectric constant capacitor ceramic (barium titanate-titanium oxide) is extruded into a circular tube, a wafer, or a disk as a medium, and silver is plated on the ceramic as an electrode by the infiltration method. It is divided into two types of high-frequency porcelain and low-frequency porcelain. Capacitors with a small positive capacitance temperature coefficient are used in highly stable oscillating circuits as circuit capacitors and pad capacitors. Low-frequency ceramic dielectric capacitors are limited to bypass or DC-blocking in circuits with low operating frequencies, or where stability and loss requirements are not high (including high frequencies). Such capacitors are not suitable for use in pulsed circuits because they are prone to breakdown by pulsed voltages.

classification:

Ceramic capacitors can be divided into plug-in and chip types according to different packages! According to different dielectrics, it can be divided into type I ceramic capacitors and type II ceramic capacitors. Generally, NP0, SL0, and COG are class I ceramic capacitors, and X7R, X5R, Y5U, and Y5V are class II ceramic capacitors. The capacity stability is very good, and it basically does not change with temperature, voltage, time and other changes, but generally the capacity is very small, and the stability of the capacity of type II ceramic dielectric capacitors is very poor. With temperature, voltage, and time, the change range is large, so Generally used in places where capacity stability is not high, such as filtering!

Important parameter:

Capacitance

2. Rated voltage

3. Tolerance

4. Size

C = (εoεr A) / d

εo is the permittivity of free space

εr is the relative dielectric constant

A is the area of a plate

d is the separation between the plates.

use:

High-voltage ceramic capacitors used in high-power, high-voltage fields require small, high withstand voltage and good frequency characteristics. With the progress of materials, electrodes and manufacturing technology, the development of high-voltage ceramic capacitors has made considerable progress and has been widely used. High-voltage ceramic capacitors have become one of the indispensable components of high-power high-voltage electronic products. The use of high-voltage ceramic capacitors is mainly divided into power equipment for power transmission and distribution systems and equipment for processing pulse energy.