Ceramic capacitors are among the most common types of capacitors that are found being used in various electrical instruments because of their reliability and cost less to manufacture. These capacitors are known to have porcelain discs and are said to exist in a non-polarised form used in various industries. These capacitors use ceramic as their dielectric, which has poor conductivity and efficiently supports the electrostatic fields. This capacitor consists of many alternating layers of ceramic material and a metal layer utilized as an electrolyte. The ceramic material composition in these capacitors indicates its electrical behaviour and its applications. In simple words, a ceramic capacitor is known as a fixed capacitor in which the ceramic is used as a dielectric material.
Types of Ceramic Capacitor
Two common types of capacitors are known:
Ceramic Disc Capacitors
Ceramic disc capacitors are used for safety purposes, primarily in electromagnetic interference suppression capacitors. These capacitors are made by coating the ceramic discs with silver contacts on each side. They hold a capacitance value ranging from about10pF to 100μF and have various voltage ratings between 16 V to 15 kV.
Multi-Layered Ceramic Capacitors
Ceramic capacitors with multiple layers are widely used in various applications and industries. These capacitors are available in different sizes and shapes and are mainly used for RFI/EMI suppression systems. Multi-layered capacitors are also used as feed-through capacitors, and large dimension systems are used as power capacitors in transformers. These capacitors are manufactured with a mix of paraelectric and ferroelectric materials. When the layering process has been completed, the device's temperature is increased, and the temperature is sintered, which produces a ceramic material with desired properties. The MLCCs include more than 500 layers, and the minimum thickness is 0.5 microns.
Characteristics of Ceramic Capacitors
Ceramic capacitors have the following characteristics or properties which make them efficient.
Accurate tolerances and Precision
ceramic capacitors are commonly used with devices that need high stability and low losses. These capacitors are known to provide accurate results, and their capacitance values remain with the applied voltage, temperature, and frequency.
High Power and High Voltage
ceramic capacitors are manufactured to survive in high voltages, and they are known as power capacitors. These capacitors are much larger than the printed circuit boards. They also consist of terminals that provide safer connections to the high voltage supply. The power ceramic capacitors can tolerate voltages ranging from 2kV- to 100 kV.
Benefits of Small Size
The small size of these ceramic capacitors has its advantages in the case of packaging. For example, the measure of a "0402" multi-layered ceramic capacitor would be about 0.4 mm x 0.2 mm.
Applications of Ceramic Capacitors
Applications of ceramic capacitors are:
- Ceramic capacitors are used in transmitter stations.
- They are also utilized in induction furnaces.
- These capacitors are commonly used in high-voltage laser power supplies.
- Ceramic capacitors have been widely used on printed circuit boards.
- Such capacitors are used in power circuit breakers.
- They are used in high-density applications as well.
- Ceramic capacitors can also be used as general-purpose capacitors and across the brushes of the Direct Current motors to decrease the radiofrequency noise as much as possible.
With such a wide range of applications, less cost of manufacturing, and superior properties, we can say that these capacitors are highly effective and efficient.
