Capacitor Tutorial Includes:
Capacitor uses Capacitor types Electrolytic capacitor Ceramic capacitor Tantalum capacitor Film capacitors Silver mica capacitor Super capacitor SMD capacitor Specifications & parameters How to buy capacitors - hints & tips Capacitor codes & markings Conversion table
The ceramic capacitor gains its name from the fact that it uses ceramic materials for its dielectric.
Although the ceramic capacitor has been used for many years as a leaded device, it is a surface mount device where its properties enable the very small capacitor sizes to be achieved while still retaining high levels of performance. As a result, countless billions of these ceramic capacitors are used each year.
Ceramic capacitor basics
The ceramic dielectric used in these capacitors gives the many properties including a low loss factor, and a reasonable level of stability, but this depends upon the exact type of ceramic used.
Ceramic dielectrics do not give as high a level of capacitance per unit volume as some types of capacitor and as a result ceramic capacitors typically range in value from a few picofarads up to values around 0.1 µF.
For leaded components, disc ceramic capacitors are widely used. This type of ceramic capacitor is extensively for applications like decoupling and coupling applications. More highly specified capacitors, especially used in surface mount types of capacitor often have specific types of ceramic dielectric specified.
Ceramic capacitor types
There are many different types of ceramic that can be used as the dielectric in ceramic capacitors.
The more commonly seen types include:
- COG: Normally used for low values of capacitance. It has a low dielectric constant, but gives a high level of stability.
- X7R: Used for higher capacitance levels as it has a much higher dielectric constant than COG, but a lower stability.
- Z5U: Used for even higher values of capacitance, but has a lower stability than either COG or X7R.
Whilst these types are commonly seen, very many other types of ceramic dielectric are available. To help with their use, different classes have been developed to help simplify the situation.
|Ceramic Capacitor Dielectric Summary|
|Class 1||These ceramic capacitors offer a high level of stability and exhibit low loss levels and they are ideal for use in resonant circuits.||NP0, P100, N33, N75, etc.|
|Class 2||Class 2 ceramic capacitors offer high volumetric efficiency, i.e. large capacitance for a given volume for smoothing, by-pass, coupling and decoupling applications.||X7R, X5R, Y5V, Z5U, etc.|
|Class 3||Class 3 ceramic capacitors offer higher volumetric efficiency than the class 2 ceramic capacitors, but their temperature stability is not nearly so good. A typical performance for the change of capacitance with temperature is −22% to +56% over a range of 10°C to 55°C.||Only available as leaded components. No longer standardised.|
These ceramic capacitor classes are standardised by international bodies including the IEC, International Electrotechnical Commission and the EIA, Electronic Industries Alliance.
. . . . . Read more about Ceramic Capacitor Dielectric Types.
Surface mount capacitors: MLCC
A vast number of ceramic chip capacitors are used everyday. They are used on most surface mount boards in everything from televisions to mobile phones and heating timers to automotive systems.
The surface mount capacitor uses what is called a multilayer chip capacitor, MLCC construction. Effectively, the MLCC consists of a number of individual capacitors that are stacked together in parallel with the overall contact being made via the component terminal surfaces.
Ceramic capacitor summary
The table below gives a summary of some of the salient features of ceramic capacitors.
|Ceramic Capacitor Summary|
|Typical capacitance ranges||10 pF to 0.1µF (100nF)|
|Rated voltage availability||From around 2V upwards - some specialised ones can have voltages of 1kV and more.|
More Electronic Components:
Resistors Capacitors Inductors Quartz crystals, xtals Diodes Transistor Phototransistor FET Memory types & technologies Thyristor / SCR Connectors RF connectors Valves / Tubes Battery technology Relays
Return to Components menu . . .