How to connect capacitors correctly

If you are only at the very beginning of a difficult, but very exciting path in the knowledge of electronics, then, undoubtedly, faced with the following question: How to connect capacitors correctly?

After collecting some simple circuit or repairing your favorite gadget, a situation may arise that you simply will not have the required capacitor with the correct parameters.

Of course, you can postpone repair (assembly) until you go to the radio market, or you can correctly connect (in parallel or in series) a couple of capacitors and thus get the required capacity. We will talk about the second option in this article.

Parallel connection of capacitors

The connection is shown schematically as follows:

To calculate the total capacitance of capacitors connected in parallel, it is enough to use a rather simple formula:

As you already understood, with this option of connecting the capacitors, the capacities of the individual elements are elementary added.

Important. When calculating the summing capacity, calculations must be carried out in the same units. For example, if you add up the capacities and the counting is carried out in microfarads, then the capacitances of the capacitors to be connected must be converted to microfarads and only then add.

instagram viewer

Series connection of capacitors

This connection is schematically represented as follows:

So, to calculate the total capacity of series-connected capacitors, you must use the following formula:

Connect only two capacitors and the formula becomes simplified:

After doing a few calculations, you will undoubtedly notice the following pattern: the total capacitance in a serial connection is always less than the smallest capacitance included in the connection. Let's say we decided to connect a pair of capacitors in series: 100 μF, and the second 47 μF, then the total capacitance will be as follows:

When connecting capacitors of the same capacity, the calculation formula will be as follows:

where M is the number of capacitors to be connected;

C1 is the capacity of a single capacitor.

Important addition

When connecting capacitors, you need to pay attention not only to the resulting capacitance, but to another very important parameter -
U number.

By connecting capacitors in series, then the voltage between them will be distributed in inverse proportion to their capacitances. This means that when connecting in series, it is necessary to use capacitors with U nom equal to the one we replace with our assembly.

If capacitors with identical capacitance are used, then the voltage between them is distributed equally.

A few words about electrolytic capacitors

If you are connecting electrolytic capacitors, then you need to observe polarity in the strictest manner.

• With a parallel connection, connect minus to minus, plus to plus.
• When connecting in series "+" of one capacitor, connect to "-" of another capacitor.
• It is also highly desirable to use capacitors of the same type and from the same batch when implementing a composite capacitor. In this case, the spread of the parameters of the components used will be minimal.

About the mixed connection of capacitors, I see no reason to talk because of the extremely small practical application (well, at least I have never seen such a thing). Such a connection is used only in physics problems.

If you liked the article, then you can always rate it like. This will help the development of the project. Thanks for attention!