A complete list of commonly used capacitors (with pictures)

1. Aluminum electrolytic capacitor

A capacitor made of absorbent paper soaked in a paste electrolyte sandwiched between two aluminum foils, with a thin oxide film as the dielectric. Because the oxide film has a unidirectional conductive property, the electrolytic capacitor has polarity. It has a large capacity and can withstand large pulsating currents, large capacity errors, and large leakage currents; ordinary ones are not suitable for use at high frequencies and low temperatures, and should not be used for low-frequency bypass, signal coupling, and power filtering at frequencies above 25kHz.
Capacitance: 0.47~10000u
Rated voltage: 6.3~450V
Main features: small size, large capacity, large loss, and large leakage
Applications: power filtering, low-frequency coupling, decoupling, bypass, etc.
2. Tantalum electrolytic capacitor (CA) Niobium electrolytic capacitor (CN)

Sintered tantalum block is used as positive electrode, and solid manganese dioxide is used as electrolyte. The temperature characteristics, frequency characteristics and reliability are better than ordinary electrolytic capacitors, especially the leakage current is very small, the storage is good, the life is long, the capacity error is small, and the volume is small. The maximum capacitance voltage product can be obtained per unit volume. The tolerance to pulsating current is poor. If damaged, it is easy to short-circuit. It is used in ultra-small and highly reliable parts.
Capacitance: 0.1~1000u
Rated voltage: 6.3~125V
Main features: loss and leakage are less than aluminum electrolytic capacitors
Application: Replace aluminum electrolytic capacitors in circuits with high requirements
3. Film capacitors

The structure is similar to that of paper capacitors, but the medium uses low-loss plastic materials such as polyester and polystyrene. The frequency characteristics are good, the dielectric loss is small, and it cannot be made into a large capacity. The heat resistance is poor. Filters, integration, oscillation, and timing circuits.
a Polyester (polyester) capacitor (CL)
Capacitance: 40p~4u
Rated voltage: 63~630V
Main features: small size, large capacity, heat and humidity resistance, poor stability
Application: low-frequency circuits with low requirements for stability and loss
b Polystyrene capacitor (CB)
Capacitance: 10p~1u
Rated voltage: 100V~30KV
Main features: stable, low loss, large size
Application: circuits with high requirements for stability and loss
c Polypropylene capacitor (CBB)
Capacitance: 1000p~10u
Rated voltage: 63~2000V
Main features: performance is similar to polystyrene but small size, slightly poor stability
Application: replace most polystyrene or mica capacitors, used in circuits with higher requirements
4. Ceramic dielectric capacitor

Through-type or pillar-type ceramic capacitors, one of its electrodes is the mounting screw. The lead inductance is extremely small, the frequency characteristics are good, the dielectric loss is small, and there is temperature compensation. It cannot be made into a large capacity, and vibration will cause the capacity to change. It is particularly suitable for high-frequency bypass.
a High-frequency ceramic capacitor (CC)
Capacitance: 1~6800p
Rated voltage: 63~500V
Main features: low high-frequency loss, good stability
Application: high-frequency circuit
b Low-frequency ceramic capacitor (CT)
Capacitance: 10p~4.7u
Rated voltage: 50V~100V
Main features: small size, low price, high loss, poor stability
Application: low-frequency circuit with low requirements
5. Monolithic capacitor

(Multilayer ceramic capacitor) is made by coating electrode paddle material on several ceramic film blanks, stacking them and winding them into an inseparable whole at one time, and then encapsulating them with resin to form a new type of capacitor with small volume, large capacity, high reliability and high temperature resistance. The low-frequency monolithic capacitor with high dielectric constant also has stable performance, small size, high Q value, large capacity error, noise bypass, filter, integration, oscillation circuit.
Capacity range: 0.5PF~1UF
Withstand voltage: twice the rated voltage.
Large capacitance, small size, high reliability, stable capacitance, good high temperature resistance and moisture resistance, etc.
Application range: widely used in electronic precision instruments. Various small electronic devices are used for resonance, coupling, filtering and bypass.
6. Paper capacitor

Generally, two aluminum foils are used as electrodes, separated by capacitor paper with a thickness of 0.008-0.012mm, and wound together. The manufacturing process is simple, the price is cheap, and a large capacitance can be obtained.
Generally, it is used in low-frequency circuits and cannot be used at frequencies higher than 3-4MHz. The withstand voltage of oil-immersed capacitors is higher than that of ordinary paper capacitors, and the stability is also good, which is suitable for high-voltage circuits.
7. Fine-tuning capacitor

The capacitance can be adjusted within a small range and can be fixed to a certain capacitance value after adjustment. Ceramic fine-tuning capacitors have high Q values ​​and small volumes. They are usually divided into two types: round tube type and round disc type. Mica and polystyrene dielectrics usually use spring-type capacitors, which have simple structures but poor stability. Wirewound ceramic fine-tuning capacitors change the capacitance by removing the copper wire (external electrode), so the capacitance can only be reduced, and are not suitable for use in situations where repeated debugging is required.
a Air dielectric variable capacitor
Variable capacitance: 100~1500p
Main features: low loss, high efficiency; can be made into linear, linear wavelength, linear frequency and logarithmic types according to requirements
Applications: electronic instruments, radio and television equipment, etc.
b Film dielectric variable capacitor
Variable capacitance: 15~550p
Main features: small size, light weight; loss is greater than that of air dielectric
Applications: communications, broadcast receivers, etc.
c Film dielectric fine-tuning capacitor
Variable capacitance: 1~29p
Main features: large loss, small size
Applications: circuit compensation for tape recorders, electronic instruments, etc.
d Ceramic dielectric fine-tuning capacitor
Variable capacitance: 0.3~22p
Main features: small loss, small size
Applications: precision-tuned high-frequency oscillation circuits
8. Ceramic capacitor

Capacitor ceramics with high dielectric constant (barium titanate-titanium oxide) are extruded into round tubes, discs or disks as dielectrics, and silver is plated on the ceramics as electrodes by the sintering method. It is divided into high-frequency ceramic dielectrics and low-frequency ceramic dielectrics. Capacitors with small positive capacitance temperature coefficients are used in high-stability oscillation circuits as loop capacitors and pad capacitors. Low-frequency ceramic capacitors are limited to bypass or DC isolation in circuits with lower operating frequencies, or in situations where stability and loss requirements are not high (including high frequencies). This type of capacitor is not suitable for use in pulse circuits because they are easily broken down by pulse voltages. High-frequency ceramic capacitors are suitable for high-frequency circuits.
9. Glass glaze capacitors (CI)

It is made of a special mixture with a concentration suitable for spraying, which is sprayed into a thin film. The medium is then sintered with a silver layer electrode to form a "monolithic" structure. The performance is comparable to that of mica capacitors. It can withstand various climate environments. It can generally work at 200℃ or higher. The rated working voltage can reach 500V, and the loss tgδ is 0.0005～0.008.
Capacitance: 10p～0.1u
Rated voltage: 63～400V
Main features: good stability, low loss, high temperature resistance (200 degrees)
Application: pulse, coupling, bypass and other circuits