What Causes Thin Film Capacitor to Crack

Thin film capacitors are capacitors composed of one or two layers of insulating film. The insulating film of thin film capacitors is generally made of polymer materials such as polyimide, polypropylene, or inorganic materials such as aluminum oxide. Thin film capacitors are generally small in size and have large capacitance values, which can be widely used in electronic circuits, communication systems, power supply equipment, and other fields. Generally, the service life is relatively long, but there is also a phenomenon of cracking, and the application time is not long. The following is a brief analysis of the reasons for the bursting of thin film capacitors for your reference.

1. Improper selection of capacitance

Select the preferred capacitor correctly. There are many types of thin film capacitors. For example, if it is a conventional circuit, a CBB22 capacitor is typically used. "If the voltage is high and the current is high, we can use CBB81 or MMKP82 capacitors, or because the capacitor selection is incorrect, the thin film capacitor may burst.".

2. Thin film capacitor material is poor

Thin film capacitors belong to a relatively high level of production automation, so theoretically, the cost difference for each household is not significant. However, some manufacturers will compete in thin film capacitor materials in order to fight a price war and lower the cost of their brands, such as selecting fake and inferior films from small manufacturers, or even selecting cheap and inferior metal films. Many manufacturers in the industry directly purchase defective products produced by metal film manufacturers, The cost of thin film capacitors produced from this type of thin film is indeed very low, but the service life of the capacitors can also be very poor, and they can easily burst during use.

3. Circuit temperature too high

The maximum temperature resistance of thin film capacitors is generally 105 ℃/10 ℃ (please note that some inexpensive thin film capacitors have a maximum temperature resistance of only 85 ℃, which is an obsolete product, but many manufacturers are selling it). If there are electronic components with high heating capacity next to the thin film capacitor, or the heat removal of the entire circuit is not very good, due to excessive temperature, it is easy to cause the thin film capacitor to burst.

4. Low pressure fake high pressure

This is the most commonly used technique for low-cost thin film capacitors. Due to the largest cost proportion of thin film capacitor materials, regular thin film capacitors have a compressive capacity of 1.6 to 2 times. In order to make product quotations more competitive, some manufacturers prefer to use thin film capacitors with low current ratings to fake high-voltage capacitors. Due to the use of fewer raw materials, this type of capacitor is significantly smaller in volume, and its compressive strength is insufficient, making it easy to burst during use.

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