Type of Capacitor
Electrolytic
- Made of electrolyte, Aluminum electrodes are used by using a thin oxidation membrane
- Polarized capacitor
- Cheap, readily available, good for storage of charge (energy) availablein very small or very large values in μF- Not very accurate, marginal electrical properties, leakage, drifting, not suitable for use in hf circuits
Tantalum
- Made of Tantalum Pentoxide. They are electrolytic capacitors butused with a material called tantalum for the electrodes. Superior to electrolytic capacitors
- Nonpolarized capacitor
- Excellent temperature and frequency characteristics,lack of current-spike-noise. Small size fits anywhere, reliable, most common values readily available.
- Expensive, easily damaged by spikes
Polyester Film
- This capacitor uses a thin polyester film as a dielectric.
- Nonpolarized capacitor
- Not as high a tolerance as polypropylene, cheap, temperature stable,readily available, widely used. Tolerance is approx 5% to 10%.
- Can be quite large depending on capacity or rated voltage and so may not be suitable for all applications.
Polypropylene
- This capacitor uses polypropylene film is the dielectric.
- Nonpolarized capacitor
- Very little change in capacitance when these capacitors are used in applications within frequency range 100KHz. Tolerance is about 1%
- higher tolerance is needed then polyester caps can offer . Very small values are available.
Metalized Polyester Film
- Dielectric made of Polyester or DuPont trade name "Mylar".
- Nonpolarized capacitor
- Good quality, low drift, temperature stable. Because the electrodesare thin they can be made very very small. Good all-round capacitor.
Epoxy
- Manufactured using an epoxy dipped polymers as a protective coating.
- Nonpolarized capacitor
- Widely available, stable, cheap.
- large depending on capacity or rated voltage and so may not be suitable for all applications.
Ceramic
- Constructed with materials such as titanium acid barium for dielectric. Internally these capacitors are not constructed as a coil
- Nonpolarized capacitor
- Well suited for use in high frequency applications. Typically used to by
-pass high frequency signals to ground. They are shaped like a disk, available in very smallcapacitance values and very small sizes. ,very small size and value, very cheap, reliable
- Together with the electrolytics the most widely available and used capacitor around. Subject to drifting depending on ambient temperature.
Multilayer Ceramic
- Dielectric is made up of many layers.
- Nonpolarized capacitor
- Small in size, very good temperature stability, excellent frequency stable characteristics. Multilayer caps suffer from high-Q internal (parallel) resonances
- generally in the VHF range. The CK05 style 0.1μF/50V caps for example resonate around 30MHz. The effectof this resonance is effectively no apparent capacitance near the resonant frequency.As with all ceramic capacitors, be careful bending the legs or spreading them apart to closeto the disc body or they may get damaged.