The difference between ceramic capacitors and high frequency ceramic capacitor

     Most people think that ceramic capacitors and high-frequency ceramic dielectric capacitors are two relatively similar capacitors. In fact, there is a difference between ceramic capacitors and high-frequency ceramic dielectric capacitors. High frequency ceramic capacitor is a kind of ceramic high capacitor. The following is a brief introduction to the difference between ceramic capacitors and high-frequency ceramic dielectric capacitors.

     Ceramic capacitors are made by extruding capacitor ceramics with high dielectric constant into a round tube, disc or disk as a 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 two kinds. Ceramic capacitor A capacitor with a small positive capacitance temperature coefficient used in highly stable oscillation circuits as a loop capacitor and as a packing capacitor.

     Low-frequency ceramic dielectric vessels are limited to bypass or DC isolation in circuits with low operating frequencies, or where stability and loss requirements are not high (including high frequencies). Such capacitors should not be used in pulse circuits because they are easily broken down by pulse voltages.

     The high frequency ceramic dielectric vessel is made of a thin film sprayed with a special mixture of suitable spraying concentration, and the medium is sintered with a silver layer electrode to form a monolithic structure. High frequency ceramic capacitor is suitable for high frequency mica capacitor. In terms of structure, it can be divided into foil type and silvered type. The silver electrode is directly deposited on the mica sheet by vacuum evaporation method or sintering method, and the temperature coefficient is greatly reduced because of the elimination of air gap, and the capacitance stability is higher than that of foil.

     High frequency ceramic dielectric vessel has good frequency characteristics, high Q value and low temperature coefficient. Can not be made into large capacity; It is widely used in high frequency electrical appliances and can be used as a standard glass glaze capacitor. The performance can be comparable to that of mica capacitors, can withstand various climatic environments, generally can work at 200 ° C or higher temperatures, and the rated operating voltage can reach 500V.