Ceramic capacitors used in the electronic field are required to have the characteristics of small size, high withstand voltage and good frequency characteristics.
With the advancement of materials, electrodes and manufacturing technology, the development of high-voltage ceramic capacitors has made considerable progress and has been widely used. Ceramic capacitors have become one of the indispensable components of high-power and high-voltage electronic products.
Using high-dielectric constant capacitor ceramic barium titanate titanium monoxide extruded into a tube, wafer or disc as the medium, and using the sintering method to plate silver on the ceramic as an electrode. It is divided into high-frequency porcelain and low-frequency porcelain. Capacitors with small positive capacitance temperature coefficients are used in high-stability oscillation circuits as loop capacitors and pad capacitors. Low-frequency ceramic capacitors are limited to bypass or DC blocking in circuits with lower operating frequencies, or occasions where stability and loss are not high (including high frequencies). Such capacitors are not suitable for use in pulse circuits because they are easily broken down by pulse voltage.
As people’s demand for electronic equipment has calmed down, the problem of “howling” caused by capacitor vibration, which has not been paid attention to, has been the problem of “howling” caused by capacitor vibration in the power circuit of various application equipment such as notebook computers, mobile phones, and digital cameras (DSC). Become a design issue.
Ceramic capacitors are also called ceramic capacitors or monolithic capacitors. As the name suggests, a ceramic dielectric capacitor is a capacitor whose dielectric material is ceramic. According to the different ceramic materials, it can be divided into low-frequency ceramic capacitors and high-frequency ceramic capacitors. Classified according to the structure, it can be divided into wafer capacitors, tubular capacitors, rectangular capacitors, chip capacitors, through-core capacitors and so on.
Traditional ceramic capacitors have materials with a lower dielectric constant than traditional ceramic materials and can reduce the distortion of the capacitor, and install ceramic capacitors on the terminal board of the circuit board and other parts, and suppress the vibration transmission of the circuit board. Type capacitors with metal terminals, the degree of howling is confirmed by human ears. In the frequency range of 0Hz to 12.75kHz, the frequency of the rectangular wave is adjusted to the resonance frequency of the capacitor and the circuit board by using the software in the computer to generate howling. Howling phenomenon, howling principle.