Basic Electronics

The fundamental relationship between voltage, current and resistance in an electrical circuit is called Ohm’s Law. All materials are made up from atoms, and all atoms consist of protons, neutrons andelectrons.Protons,have a positive electrical charge. Neutrons have no electrical chargewhile Electrons, have a negative electrical charge. Atoms are bound together by powerful forces of attraction existing between the
atoms nucleus and the electrons in its outer shell. When these protons, neutrons and electrons are together within the atom they are happy and stable. But if we separate them from each other they want to reform and start to exert a
potential of attraction called a potential difference. Now if we create a closed circuit these loose electrons will start to move and drift back to the protons due to their attraction creating a flow of electrons. This flow of electronsis called an electrical current. The electrons do not flow freely through the circuit as the material they move through creates a restriction to the electron flow. This restriction is called resistance. Then all basic electrical or electronic circuits consist ofthree separate but very much related electrical quantities called: Voltage, ( v ), Current, ( i ) and Resistance, ( O ). called: Voltage, ( v ), Current, ( i ) and Resistance, ( O ).

A capacitor is a passive two-terminal electrical component used to store electrical energy temporarily in an electric field. When used in a direct current or DC circuit, a capacitor charges up to its supply voltage but blocks the flow of current through it because the dielectric of a capacitor is non-conductiveand basically an insulator. However, when a capacitor is connected to an alternating current or AC circuit, the flow of the current appears to pass straight through the capacitor with little or no resistance.

A diode is a specialized electronic component with two electrodes called the anode and the cathode. Most diodes are made with semiconductor materials such as silicon, germanium, or selenium. Some diodes are comprisedof metal electrodes in a chamber evacuated or filledwith a pure elemental gas at low pressure.Diodes can be used as rectifiers, signal limiters, voltage regulators, switches, signal modulators,signal mixers,signal demodulators, and oscillators.
The field-effect transistor (FET) is a transistor that usesan electric field to control theshape and hence the electrical conductivity of a channel of one type of charge carrier in a semiconductor material. FETs are also known as unipolartransistors as they involve single-carrier-type operation. The FET has several forms, but all have high input impedance.While the conductivity of a non-FET transistor is regulated by theinput current (the emitter to base current) and so has a low input impedance, a FET's conductivity is regulatedby a voltage applied to a terminal (the gate) which is insulated from the device. The applied gate voltage imposes an electric field into the device, this in turn attracts or repels charge carriers to or from the region between a source terminal and a drain terminal. The density of charge characters in turn influences the conductivity between the source and drain.

Inductors are used to store energy while also filtering EMI currents with a low-loss inductance for voltage conversion applications. They are also used in DC-to-DC converters for a wide range of products in a variety of applications. Requiring minimal printedcircuit board (PCB) space, power inductors providea high-performance, multiphase design thatsignificantly reduces the overall system cost.


A resistor is a passive two-terminal electricalcomponent that implements electrical resistanceas a circuit element. Resistors act to reduce current flow, and, at the same time, act to lower voltage levels within circuits. In Laptop circuits,resistors are used to limit the current flow.

Resistors can also be connected together in various series and parallel combinations to form resistor networks which can act as voltage droppers,voltage dividers or current limiters within a circuit.