What is the difference between electrolytic capacitor and thin film capacitor What is the difference between electrolytic capacitor and thin film capacitor

There are electrolyte materials for storing charge inside the electrolytic capacitor, which are divided into positive and negative polarity, similar to batteries, and cannot be reversed. The positive electrode is a metal substrate with an oxide film, and the negative electrode is connected to the electrolyte (solid and non-solid) through a metal plate.

Polar electrolytic capacitors are usually used for power filtering and decoupling in power supply circuits or intermediate and low frequency circuits（ ǒ u) Signal coupling, time constant setting, DC isolation, etc. The non-polar electrolytic capacitor is usually used in the audio frequency divider circuit, the television s correction circuit and the starting circuit of the single-phase motor.

The working voltage of electrolytic capacitor is 4V, 6.3V, 10V, 16V, 25V, 35V, 50V, 63v, 80V, 100V, 160V, 200V, 300V, 400V, 450V and 500V, and the working temperature is - 55 ° ~ + 155 ℃ (4 ~ 500V). It is characterized by large capacity, large volume and polarity. It is generally used for filtering and rectification in DC circuits. At present, the most commonly used electrolytic capacitors are aluminum electrolytic capacitors and tantalum electrolytic capacitors.

A thin film capacitor is a capacitor with a metal foil as an electrode, which is overlapped with a plastic film such as polyethylene, polypropylene, polystyrene or polycarbonate from both ends and wound into a cylindrical structure. According to the type of plastic film, it is also called polyethylene capacitor (also known as mylar capacitor), polypropylene capacitor (also known as PP capacitor), polystyrene capacitor (also known as PS capacitor) and polycarbonate capacitor.

Thin film capacitor is an excellent capacitor because of its many excellent characteristics. Its main characteristics are as follows: non polarity, high insulation impedance, excellent frequency characteristics (wide frequency response), and small dielectric loss.

Therefore, the difference between electrolytic capacitor and thin film capacitor is obvious. The main points are as follows:

Life: electrolytic capacitors generally have life parameters, while thin film capacitors have no life, which can last for decades.

Capacitance value: the capacitance value of electrolytic capacitor can be very large, and high voltage and high capacitance value. The capacitance value of the film capacitor is relatively small. If you need a larger capacitance value, the film capacitor is uncertain.

Size: as for the specifications, the size of the thin film capacitor is larger than that of the electrolytic capacitor.

Polarity: electrolytic capacitors are divided into positive and negative electrodes, while thin film capacitors are not divided into non-polar capacitors. Therefore, it can be separated on the lead. The lead of electrolytic capacitor is one high and one low, and the lead of thin film capacitor is the same length.

Accuracy: the electrolytic capacitance is generally 20%, and the film capacitance is generally 10% and 5%.