Different capacitors

Capacitors are divided into two categories – polarized and non-polarized.


Polarized capacitors can be given a positive voltage in one direction and can be placed in one direction. Polarized capacitors are electrolytic and tantalum capacitors


Non-polarized is a ceramic capacitor, a polyester capacitor, a paper capacitor that has no polarity and can be placed in all directions.

Types of capacitors

Capacitor selection parameters

When a capacitor is selected in any circuit, users must take care of the following parameters in addition to the application / use.

  • Capacity value
  • Maximum capacitor operating voltage.
  • Tolerance
  • Voltage failure
  • Group
  • Resistance in the corresponding series, (ESR)
  • size
  • Manufacturer: AVX, Kemet, Vishay, Samsung, Panasonic TDK, Murata etc.


Inductors (also called coils or coils) are a passive bipolar electrical component that stores magnetic energy when an electric current passes through it. It is an insulated wire wound on a coil around the core of a spiral-shaped material (air, iron, iron powder or ferrite material).

The inductor is denoted by the inductance “L”, and the unit of measurement is Henry (H). Inductor values ​​are usually from 1 µH to 2000 mH.

Inductive symbols

When a time-varying current passes through the inductor, a magnetic field is generated that induces an electric motor force (e.m.f.) (voltage) in the inductor. The voltage V is given along the inductor of the inductor L

V = L di / dt

In other words, there is only a voltage across the inductor if the current flowing through it changes; DC does not produce inductor voltage. The inductor usually blocks AC and transmits DC.

The energy stored in the Henries “L” value is obtained;

E = 1/2 Li² energy E is in joules and I in amperes.

The ideal inductor has zero resistance and zero capacity. However, real inductors have a low value resistance associated with the winding of the coil and, when current flows through it, energy is lost in the form of heat.

Use of inductors

In buck / boost effect controls.
In DC filter circuits.
Isolate the signals
In the transformer to increase / decrease the AC voltage level
In oscillators and control circuits
For generating voltage peaks in fluorescent series.
Types of inductors

Inductors are mainly classified according to the nuclear material used and the operating frequency. The following are different types of inductors and are available on both the port and the SMD package.

  • Iron core inductors
  • Air conditioning inductors
  • Iron powder inductors
  • Ferrite core inductors
  • Variable inductors
  • Sound frequency inductors
  • Radio frequency inductors
  • Types of inductors
  • Types of inductors
  • Parameters for inductor selection

When selecting an inductor in any circuit, the user must take care of the following parameters in addition to the application / use.

  • Inductance value
  • Tolerance
  • The highest current assessment
  • Protected and unprotected
  • size
  • Rankings Q
  • Group
  • Inductor response
  • Type of core used


A diode is two terminal semiconductor devices that allow electric current to flow in one direction and block it in the opposite direction. The diode consists of a semiconductor with P and N type material. The typical materials of the diode are silicon and germanium. They work when the minimum output voltage (~ 0.7 V for silicon) is applied over it and remains off during reverse polarization.