Capacitance in series and in parallel and capacitance in series and balance resistance

There are two kinds of super capacitors in your hand , Super capacitors are two capacitors connected in series , But a super capacitor adds a balance resistor , The other one does not add balance resistance ; In practical applications, parallel resistors are often used , Less series capacitors are used , Even if you use a large super capacitor, you can use it directly , It's better not to pay attention to the quality of the capacitor , also Did not pay attention to the internal structure of supercapacitors , Here's the picture ：

  It can be seen that the following capacitor is added with a balance resistance in the series capacitor , This kind of capacitor with balance resistance must be better , Quality can be better guaranteed , Therefore, in the actual circuit design process, if you need to use capacitors in series, you'd better add balance resistance .

        Capacitance is the basic component of the circuit , It is a kind of device used more than resistance , It shows low impedance characteristics for high-frequency signals , It is often used for filtering 、 Energy storage 、 Oscillation circuit and other circuits , So how to use capacitors in series and parallel ？

1、 Capacitors are connected in series

Voltage withstand value after capacitor is connected in series 、 Capacity, etc. will change , Performance presented redistributes individual capacitors , The voltage withstand value will increase after the capacitor is connected in series , But the capacity is not necessarily increased , Therefore, when the withstand voltage value of a capacitor is not enough, a capacitor can be connected in series , But here's the problem , Capacitors are not ideal , There will be leakage current , In other words, the voltage on the two capacitors connected in series may be different , Therefore, if you want to connect in series, you'd better use capacitors of the same specification , This ensures consistency , At the same time, a resistor is distributed at both ends of the capacitor , In this way, the problem of capacitor voltage equalization can be better guaranteed , And the current flowing through this resistor is several times more than the leakage current , In this way, the influence of leakage current on voltage sharing can be basically ignored , Here's the picture ：

2、 Capacitor paralleling

        Voltage withstand value after capacitor is connected in parallel 、 Capacity, etc. will also change , It should also be analyzed in detail according to the actual circuit , But the capacity is undoubtedly increased , Therefore, if the capacity of a single capacitor cannot meet the circuit design, we can consider the way of paralleling two capacitors to increase the capacity of the capacitor , The filtering effect is sometimes better than that of a capacitor in parallel , Especially when using a large and a small capacitor , Because big ones can filter out low frequencies , Small ones can filter out high frequencies , In some circuits, sometimes the heat dissipation effect will be better , But capacitors can't be connected in parallel too much , Because considering the problem of frequency point oscillation . The parallel capacitance is shown in the following figure ：

 

summary ：

① For series capacitors , The total capacity of the capacitor is the reciprocal and one-half of the capacity of each capacitor , That is, the total resistance in parallel with the resistance is a truth , But the withstand voltage is the sum of the total capacitance ;② For shunt capacitors , The capacity is the sum of each capacitance , The voltage withstand requirement is subject to the lowest one ;③ Because the capacitance and withstand voltage are different , Therefore, for series or parallel connection , The withstand voltage needs to be reconsidered .