Ceramic capacitors KM. Features, scope

A capacitor is a radio electronic device designed to store electric charge and field energy. There are many types of capacitors and their designs. In this article, let's talk about ceramic capacitors such as CM. Capacitors of this type are used in industrial equipment, in the manufacture of high precision instruments , radio transmitting devices, as well as in the military industry.

KM ceramic capacitors are highly stable, they are designed for operation in pulse modes, as well as in alternating and direct current circuits. They are characterized by high adhesion of the plates to the ceramic, as well as slow aging, which provides a low value of the coefficient of capacitive temperature instability. Condensers of CM with a fairly small size have a high capacity (reaching 2.2 μF). However, the change in the capacitance value in the temperature range of ceramic capacitors KM is from 10 to 90%.

Condensers of group K CM are most often used as transitional, blocking, etc. Modern ceramic capacitors of CM are manufactured by pressing under pressure in a monolithic block of thin metallized ceramic plates. Due to the high strength of the material mentioned, it is possible to use the blanks very thin, as a result, the capacitance of the capacitors obtained, proportional to unit volume, increases sharply.

Condensers of type KM also differ from other capacitors by their high price. The reason is that the following precious metals (and their mixtures) are used as dielectric coatings: Ag, Pl, Pd. In most cases, palladium is used, and this is the reason for their value. In connection with this, not only new products are in great demand, but also used and even become unusable. Precious metals are contained in capacitors of the type KM3-6. They are divided into two types: palladium (KM H90) and platinum (KM H30). There is another subset of capacitors KM of group H30 - this is KM5 D, which differ from H30 in that they have much less platinum. The content of precious metals in KM H90 is 46.5 g of palladium and 2.5 g of platinum per kilogram of capacitors. And in capacitors of the KM H30 type is 50 g of platinum per kilogram of capacitors. Condensers of the CM group D (green) contain 40 g. Platinum, that is, 20% less than in capacitors of the H30 group (green). Capacitors of the type KM of the group H90, bearing in their marking the letter V, contain precious metals 10% more than the capacitors of the group H90. In theory, such capacitors should be more expensive than other ceramic capacitors of the H90 group of green color. And smaller capacitors should be cheaper. In practice, all capacitors KM group H90 green are the same. The cost of CM capacitors is directly dependent on the price of precious metals, as well as the cost of refining costs. The most common ceramic capacitors KM (photo demonstrates the appearance of capacitors type KM) are capacitors KM group H90 green and orange.