ECQ-E12122JF

Film Capacitors

The ECQ-E12122JF is a film capacitor comprised of polypropylene film (PP) and aluminum electrodes. It is a component used within various types of electrical circuits for energy storage applications. It can also be used as a filter for frequency-dependent attenuating in alternating current (AC) circuits.

Application Field

Film capacitors are widely used in electronic equipment such as communication equipment, various stages of power supply systems, signal processing devices and many kinds of power electronic equipment, as well as in the power amplifier audio output stage of hi-fi equipment. In particular, when used as the decoupling capacitors for digital circuits, they can limit the arrival of high frequency interference signals, keeping the circuit operation stable.

When used as ripple-filtering capacitors for heating systems, AC motor drives, and rectifier circuits, film capacitors are especially suitable for high frequency circuits due to their low ESR (equivalent series resistance) and low inductance values. They are used in a variety of other power sources applications also including industrial power supplies, electronic ballasts. They are also used as DC power supplies, inverters, frequency converters, etc.

Working Principle

A film capacitor is made up of two or more layers of plastic film, with electrodes attached to each side of the film. Generally speaking, film capacitors have a larger capacity than any other type of capacitors. This means that they store greater levels of energy, especially higher voltages. The electrical signals absorbed by the film capacitor passes through the layer of plastic film between the electrodes without any resistance. As the electrical charge increases, electrons enter the layer of plastic film and form an electrical field. The electricity moves, between the electrodes, creating a constant electric field.

When the current passes through the capacitor, a dielectric absorption and leakage occur those can create a resistance depending on the quality of the capacitor. The dielectric absorption is a physical phenomenon caused by the relative displacement of the molecules of the dielectric due to the electric field that establishes itself between the electrodes of the capacitor; the energy, then, is absorbed by the dielectric. As a consequence, this absorption gives rise to a polarization and frequency dependence that directly affects the capacitance.

Leakage is due to the energy dispatching of the capacitors; although this phenomenon is negative, it is kept at low levels since the current doesn’t pass through the capacitor until there is a consecutive adequate quantity of charge, which won’t leak out.