Function of Resistors in Electronics

Function of Resistors in Electronics = Resistors come under passive electronic components and are extensively used in electronic circuits. So important are these components that it may be virtually impossible to build an electronic circuit without involving resistors. 

Basically the function of a resistor is always to oppose the flow of current through it and the strength of this opposition is termed as its resistance. German physicist, Sir G.S. Ohms was able to discover a definite relationship between voltage, current and resistance. According to him a potential difference or a voltage (V) across a resistor (R) is proportional to the instantaneous current (I) flowing through it and is given as: 

V = R.I

Resistors

Function of Resistors in Electronics
Resistor Image In electronic circuits, resistors play an important role to limit the current and provide only the required biasing to the vital active parts like the transistors and the ICs. for the function of a resistor in electronics through the following illustrations :

LED Current Limit

LED Current Limit: Just like transistors, LEDs too are very sensitive to high currents. A resistor when placed in series with the LEDs regulates a proper flow of current through them. To calculate the value of a series LED resistor, the following formula may be used:

R = V –( N.VLED) / I

Here R = Series LED resistor, V = supply voltage, N = number of LEDs in series, V(LED) = forward voltage of the LED used, and I = current through the LEDs (10mA optimum).

The function of a resistor is to contain the flow of electric current in an electronic circuit. Resistors are classified into two classes of resistors; fixed resistors and the variable resistors. A resistor is made of either carbon film or metal film. 

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