- A fixed resistor is a resistor that is not adjustable and it cannot be varied like a variable resistor as its value is determined at the time of manufacturing itself.
- It is one type of linear resistor. A fixed resistor is an electronic component that is the most commonly used resistor.
- Under all circumstances, a perfect resistor would have a constant ohmic resistance and this resistance would be independent of frequency, voltage, or temperature.
- The fixed resistor is also called a linear or ohmic resistor which is invented by George Westinghouse and William Stanley. Fixed resistor have their fixed value for all their characteristics like their resistance and power ranking.
- These are mainly for restricting the flow of current, dividing voltages & signal level adjustment. They are also used as current-sensing components for protection circuits and for making corrections for other circuit parameters.
Working of Fixed Resistor
- It is two terminal passive components that are used to implement electrical resistance like a circuit element.
- The flow of current throughout this resistor is directly proportional to the voltage supply across the two terminals of this resistor.
- So, this relationship can be simply signified by using Ohm’s law
V = I × R - Where ‘V’ is the voltage across the resistor, ‘I’ is the current through the resistor and ‘R’ is the resistance.
- The resistance of the fixed resistor depends on its length, diameter, and material properties. The length and diameter can be adjusted during production or after manufacturing by adding more wire or removing it.
Applications of Fixed Resistor
- It’s used in power supplies to reduce the incoming voltage.
- It is often used for biasing transistors and diodes, which means that they are used to set the working point of active devices such as diodes and transistors.
- It may be placed at various points throughout the circuit, depending on its desired effect on the overall operation of the circuit.
- They are commonly used as pull-up resistors in a digital circuit.
