Resistor (resistance = resistance) is a natural manifestation and can be found in all except the super conductive material (super conductor). The nature of a resistor going against the current direction as has been proven in Ohm’s law, where the value of the resistance (resistance) can be assumed and classified as a component of an ideal linear. But the real situation is not the case, where the value varies with the conductive material and temperature.
fixed resistor
Resistor component is a component of the most widely used in electronic circuits. Examples of applications are most often used is used as a voltage divider or current. Under the provisions of spefikasinya, kinds and types of fixed resistors are generally distinguished by the construction, the type of materials and fabrication processes. This type of material resistors are commonly in the form of carbon composition, carbon layer, carbon oxides, metal membranes, metal coating and coil wire.
As already mentioned, that in order to use many applications, the resistors are made of metal, metal oxide or metal layer is a type-resistors are commonly used. Mainly because of the type of resistor can give a range resistance is quite wide (generally range from 10 Ω to 1M Ω), has a coefficient of low temperature (up to ± 250 ppm / ° C), and has a degree of stability is very good although the state saved (not operates) and in the operational state.
Table 3.1. The order of resistors according to IEC
As for the type of carbon composition is not so much used for this type of resistor material has a very low stability factor, as well as poor temperature coefficient (estimated -1200 ppm / ºC). One way to find and mark the magnitude of the resistance value of a resistor is sufficient to provide a color code on the body. For ease in use, it is necessary to order a grouping of sizes and resistor values. Standard rules used by the IEC (International Electrical Commission), is shown in Table 3.1.