Types of Resistors
Resistors can be made of several different materials and methods. Here are a few types of resistors: carbon composition, carbon film, metal film, thick and thin film, foil resistor and wirewound. The different types have different properties. Some are very accurate, some can withstand high temperatures, some can withstand high power and some are cheap. Some are good for low noise applications, some are good for high-power applications, some for high-speed applications and some for measurement circuits.
There are so many types, but how to choose the most suitable one? Well, the most important thing to consider is the power that the resistor needs to dissipate. Power dissipation in a resistor can be calculated with the formula: P=V2/R, where P is power in Watt, V is the voltage drop over the resistor and R is the resistance of the resistor in Ohm. For most standard circuits, you don’t need to worry about the types of resistors you choose. A rule of thumb is to find a resistor with twice the power rating. Usually, you can just use the cheapest resistor you can find with the correct power rating.