What are the Functions of a Resistor in a Circuit ?

The Functions of a Resistor in a Circuit

Resistors have many uses in circuits. Most applications require multiple resistors in serial or parallel configurations. Some of the more common uses of resistors include:

⮚Potential dividers

Two or more resistors in series will give a voltage at their junction point proportional to the ratio of their values. For generating intermediate voltages in circuits  this functionality is widely used.

⮚Biasing resistors

Transistors and many other electronic devices need to have their A.C. and D.C. operating characteristics and gain values set up for correct operation. This is done with multiple resistors and is often called biasing.

⮚OP-AMP gain and feedback

Most op-amp circuits need to have their gain and feedback functionality. Resistors are the essence of doing this.

⮚Current limiting

Resistors can be used to limit the amount of current that flows in a circuit element. This is a useful safety function in many circuits e.g. limiting the current that can flow into an LED to manage its brightness.

⮚Impedance matching

To maximise power transmission at high frequencies the impedance of the receive and transmit ends of a circuit need to be the same. Resistors can perform at least part of this requirement

⮚Current measuring

Many circuits need to know how much current is flowing through it. however, it is much easier to measure voltage, so inserting a resistor into the circuit to ‘develop’ a voltage.

Ohm's law- is a common technique for measuring current.