The advantage of thin film is smaller component. This type of resistors is usually a small wattage and fixed value resistor. The metal leads with caps are fitted over each end of the substrate to make the body of the resistor. In order to deposit thin film on the substrate a photographic process is used. The thin film resistor is made by depositing a resistance material on an insulating material (glass or ceramic) substrate. The number codes printed on these resistors work in a similar manner as the color bands on the carbon resistors.
Since the size of these resistors is very small, hence does not have enough space for color code bands. These resistors are available in different shapes and sizes agreed by the Electronics Industry Alliance (EIA). The SMD resistors are made by depositing a film of resistive material. The metal film resistors are available in a wide range of resistance values ranging from a few ohms to millions of ohms. These resistances are more reliable, stable and accurate as compared to carbon resistors. The resistance value of these resistors is controlled by the thickness of coating layer. The metal film resistors are made up of metal oxide or rods of metals coated with ceramic. The carbon composition resistors are available in the resistance values ranging from 1 Ω to 22 MΩ. The cylindrical resistive element is covered with plastic to protect the resistor from outside damages. The resistive element of the carbon composition resistor is made up of the mixture of graphite powder and ceramic. The carbon composition resistors are made from a solid cylindrical resistive element with embedded metal wire leads.
The carbon composition resistor (also known as Carbon Resistor) is a type of fixed resistor that control the electric current flow to a certain level in a circuit. There are various types of fixed resistors as follow − The fixed resistor has two terminals which are used for connecting it in the circuit. The main function of an ideal fixed resistance gives a stable resistance in all situations. These resistors are available in different shapes and sizes. The fixed resistor is defined as the resistor whose resistance value does not change with the any change in temperature or voltage.
The resistor are broadly classified into two types – The circuit symbol of resistor is shown in the figure below. The measure of opposition offered by the substance in the flow electric current is known as Resistance of the substance and the element that possess the resistance is called a Resistor.