kapasitorien

Kapasitorien, also known as capacitors, are passive electrical components that store energy in an electric field formed between two conductive plates separated by a dielectric. They are widely used to store and release small amounts of energy, to filter signals, and to couple different parts of a circuit. The stored energy U is proportional to the square of the voltage across the plates.

The capacitance, measured in farads (F), depends on the plate area, the separation between the plates, and the dielectric material between them. In simple terms, C ≈ εr ε0 A / d, where εr is the relative permittivity of the dielectric, ε0 is the vacuum permittivity, A is the plate area, and d is the separation. Capacitors can have values from a few picofarads to several farads, with common discrete values found in microfarads and nanofarads.

Kapasitorien come in several major families. Ceramic capacitors are compact and non-polar; film capacitors offer stable performance and low loss; mica capacitors provide high precision; electrolytic capacitors (aluminum and tantalum) offer high energy storage but are polarized and have higher leakage and tolerance variations; paper and film/passive types are used in older or specialized applications; supercapacitors provide very high capacitance for energy storage and rapid discharge. Electrolytic capacitors are polar and must be connected with correct polarity; non-polar types are generally safer for AC or bidirectional signals.

Key electrical characteristics include rated voltage, tolerance (how much the actual capacitance can vary), leakage current, equivalent series resistance (ESR), and, for high-frequency use, equivalent series inductance (ESL). Proper selection depends on required capacitance, voltage, temperature behavior, tolerance, and the intended circuit role.