the basics electronics starts with three major components
- inductors
- capacitor
- & resistors
first let starts with...resistors. what we understands with term resistors
A resistor is an electrical component that limits or regulates the flow of electrical current in an electronic circuit. Resistors can also be used to provide a specific voltage for an active device such as a transistors.
All other factors being equal, in a direct-current (DC) circuit, the current through a resistor is inversely proportional to its resistance and directly proportional to the voltage across it. This is the well-known OHM'S LAW. In alternating-current (AC) circuits, this rule also applies as long as the resistor does not contain inductance or capacitance.
Resistors can be fabricated in a variety of ways. The most common type in electronic devices and systems is the carbon-composition resistor. Fine granulated carbon (graphite) is mixed with clay and hardened. The resistance depends on the proportion of carbon to clay; the higher this ratio, the lower the resistance.
Another type of resistor is made from winding Nichrome or similar wire on an insulating form. This component, called a wirewound resistor, is able to handle higher currents than a carbon-composition resistor of the same physical size. However, because the wire is wound into a coil, the component acts as an inductors as well as exhibiting resistance. This does not affect performance in DC circuits, but can have an adverse effect in AC circuits because inductance renders the device sensitive to changes in frequency.
second is the inductors
An inductor is a passive electronic component that stores energy in the form of a magnetic field. In its simplest form, an inductor consists of a wire loop or coil. The inductance is directly proportional to the number of turns in the coil. Inductance also depends on the radius of the coil and on the type of material around which the coil is wound.
For a given coil radius and number of turns, air cores result in the least inductance. Materials such as wood, glass, and plastic - known as dielectric materials - are essentially the same as air for the purposes of inductor winding. Ferromagnetic substances such as iron, laminated iron, and powdered iron increase the inductance obtainable with a coil having a given number of turns. In some cases, this increase is on the order of thousands of times. The shape of the core is also significant. Toroidal (donut-shaped) cores provide more inductance, for a given core material and number of turns, than solenoidal (rod-shaped) cores.
The standard unit of inductance is the Henry, abbreviated. This is a large unit. More common units are the micro henry, abbreviated µH (1 µH =10-6H) and the milli henry, abbreviated mH (1 mH =10-3 H). Occasionally, the nano henry (nH) is used (1 nH = 10-9 H).
It is difficult to fabricate inductors onto integrated circuit (IC) chips. Fortunately, resistors can be substituted for inductors in most microcircuit applications. In some cases, inductance can be simulated by simple electronic circuits using transistors, resistors, and capacitors fabricated onto ICchips.
Inductors are used with capacitors in various wireless communications applications. An inductor connected in series or parallel with a capacitor can provide discrimination against unwanted signals. Large inductors are used in the power supplies of electronic equipment of all types, including computers and their peripherals. In these systems, the inductors help to smooth out the rectified utility AC, providing pure, battery-like DC
last but not least is the capacitors
A capacitor is a passive electronic component that stores energy in the form of an electrostatic field. In its simplest form, a capacitor consists of two conducting plates separated by an insulating material called the dielectric. The capacitance is directly proportional to the surface areas of the plates, and is inversely proportional to the separation between the plates. Capacitance also depends on the dielectric constant of the substance separating the plates.
The standard unit of capacitance is the farad, abbreviated. This is a large unit; more common units are the microfarad, abbreviated µF (1 µF =10-6F) and the pico farad, abbreviated pF (1 pF = 10-12 F).
Capacitors can be fabricated onto integrated circuit (IC) chips. They are commonly used in conjunction with Transistors in dynamic random access memory (DRAM). The capacitors help maintain the contents of memory. Because of their tiny physical size, these components have low capacitance. They must be recharged thousands of times per second or the DRAM will lose its data.
Large capacitors are used in the power supplies of electronic equipment o fall types, including computers and their peripherals. In these systems,the capacitors smooth out the rectified utility AC, providing pure, battery-like DC.
