introduction to capacitors
In an electronic circuit, capacitors are widely used for the circuit design it plays many roles in a circuit a capacitor consists of two metallic plates separated by a dielectric. It can store electrical charges between the plates and it is the main advantage of a capacitor we can see many types of capacitors there are a small capacitor which is used in oscillator circuits and we can see large capacitors used in high voltage power correction the capacitor are classified mainly by the dielectric which is situated between the plates
COMMON TYPES OF CAPACITORS
• FILM CAPACITORS
• CERAMIC CAPACITORS
• ELECTROLYTIC CAPACITORS
• VARIABLE CAPACITORS
FILM TYPE CAPACITOR
It is commonly used capacitor it is available in capacitance range from 5pF to 100uF it is also called as a plastic capacitor because of the plastic used in it
advantages of film capacitors are
• It could operate at high temperatures
• It has small tolerances and very long life
• High reliability
• It is available in high voltages as high as 1500volts
• Tolerance range from 10% to 0.01%
• It is in the combination of shape and case style
• It could be used for lower capacitance values and bigger case sizes
• It could be used for frequency-stable applications
CERAMIC CAPACITORS
• It is used in high-frequency circuits
• It is the best choice for high-frequency compensation for AC circuits
• It is also called as disc capacitors
• It is made by coating two sides with a ceramic disc with silver and then stacked together to make a capacitor
• In ceramic capacitance, we could make the low and high capacitance
• It ranges from few picofarads to 1 microfarad
• Voltage ranges from few volts to thousand volts
Ceramic capacitors are inexpensive to manufacture and it has several dielectric types
ELECTROLYTIC CAPACITOR
• It has higher capacitance strength and thus it is suitable for obstruction, decoupling, and filtering
• It has higher capacitance value for its size it is mainly used when large capacitance values are required
• The dielectric which is used is really thin so large value capacitance can be created for small size
• These are polarised capacitors
• It is used in DC supplies due to their large capacitance
• It can reduce ripple voltages
VARIABLE CAPACITORS
In this type of capacitor its capacitance can be changed repeatedly by mechanical ways it is used to set frequency resonance in LC circuits and it could adjust the radio for impedance matching in the antenna tuner device
DIFFERENCE BETWEEN ELECTROLYTIC AND CERAMIC CAPACITOR
| ELECTROLYTIC CAPACITOR | CERAMIC CAPACITOR |
|---|---|
| High ESR | Low ESR |
| low-temperature stability | good temperature stability |
| high tolerance | low tolerance |
| short life | long life |
| it could be used as a filter due to its high ripple current rating | it can bypass high-frequency noise in power line |
| used in audio amplifiers | high-frequency application is preffered |