There is a lot to be said about capacitors. The previous editor talked about the method of judging the damage of SMD electrolytic capacitors, as well as the performance of new SMD safety capacitors. What kind of impact will its appearance have on the market, I always feel that it is not comprehensive enough. For the study of one thing, one cannot interpret and analyze one-sidedly, otherwise it is easy to have a single opinion. To study it, it is necessary to analyze it thoroughly, from the inside to the outside, so today we will gradually analyze the characteristics and precautions of electrolytic capacitors. First of all, let's start with Capacitor the interpretation of the structure of electrolytic capacitors. The structure of electrolytic capacitors is mainly divided into positive and negative two-pole aluminum foils and conductive solids in the middle, and the rest are electrolytes, that is, four parts of high-conductive molecular solution.
Secondly, regarding its characteristics, that is, low ESR, which means that mechanical miniaturization improves product performance. High-frequency electrical signals are extremely suitable for electrolytic capacitors, and can also take into account the circuit transmission in high-current environments. Also, the startup environment does not require as much ambient temperature, so the cost of startup conditions is lower. And it has a bright spot, that is, the self-healing ability of the dielectric solution, which can ensure that the acidified protective film will not be exhausted, and achieve low loss of circuit current. Compared with solid dielectrics, it is low-cost and high-efficiency.
The above is about the structure of electrolytic capacitors and the characteristics of the product. If you want to use a product well, you need to understand it more fully. Xiaobian will briefly talk about the points that need to be paid attention to when applying electrolytic capacitors: 1. Electrolytic capacitors should not be close to The high-power heating element in the circuit prevents the electrolyte from drying up quickly due to heating. 2. We can use the method of connecting the same polarity in series, and use two electrolytic capacitors to filter the positive and negative signals as a non-polar capacitor. 3. Electrolytic capacitors have positive and negative polarities, so we cannot connect them casually in use. In the power supply circuit, when we need to output a negative voltage, the negative pole is connected to the output terminal, and the positive pole is grounded.
When outputting a positive voltage, it is opposite to outputting a negative voltage. When the negative voltage is output, when the polarity of the filter capacitor in the power supply circuit is reversed, the output voltage of the power supply may fluctuate due to the greatly reduced filtering function. When the reverse voltage exceeds a certain value, the reverse leakage resistance of the capacitor will become very small, so the capacitor can explode and be damaged due to overheating in a short time.
