Ceramic capacitors have a ceramic core separating two metal plates enclosed in a protective cover. There are two distinct types. We distinguish these by performance. Accordingly, Class 1 ceramic capacitors deliver low losses and high stability for resonant circuit applications. Secondly, Class 2 ones offer higher volumetric efficiency for coupling, buffer, and by-pass applications.
A Short History of Ceramic Insulators
The global electronics industry consumes around one trillion ceramic capacitors annually. However this has not always been the case. Previously glass, porcelain, mica, and paper insulators were popular in early electrical days. Ceramics only featured when porcelain became scarce.
Increasingly, printed circuit boards are shrinking to accommodate demand for smaller devices. Consequently smaller capacitors are vital in achieving this goal.
For example a 0402 multi-layer ceramic capacitor similar to the picture in the preview measures just 0.4 mm x 0.2 mm. We have heard of ceramic layers as thin as 0.5 microns.
The opposite applies to large-scale capacitors with ceramic dielectrics. This these are far larger than the miniaturized ones we spoke of just now. They can cope with up to one hundred kilovolts with outputs above 200 amps and that is big.
Ceramic Capacitors (Almost) Everywhere We Go
Approximately one trillion (1012) of them leave capacitor factories every year. By American standards, that is one thousand billion.
To us, that sounds like a large number of ceramic capacitors for every human being. Would anybody like to get their smartphone out and tell us how many exactly that is?
Surface-mount ceramic capacitors are common on printed circuit boards. Class 2 ones are popular in induction furnaces, power circuit breakers, and high voltage laser power supplies. At the other end of the spectrum hobbyists and lovers of gadgets benefit from placing them across DC motors to suppress RF noise.
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