RC Time Constant,Introduction to RC CircuitHello friends! I hope you all are fine; this is the eleventh article in the series of the introduction to the basic electronic components in the previous article I have discussed about the capacitor in this article I will discuss about the combination of the resistor and capacitor.

After reading this post the reader will be able to learn about the resistor-capacitor combination, its working and applications. So sit back, keep reading and enjoy learning.

 

 

 

 

 

What is RC Circuits

An RC circuit is a combination of the resistor and the capacitor connected either in series or in parallel to each other. In the RC circuit the resistor is said to be the linear component and capacitor is said to be the dynamic component. A simple combination of the RC circuit can be described by the first order differential equation that is why it is usually called first order RC circuit.

  1. parallel RC circuit
  2. series RC circuit

 

parallel RC circuit

 

The simplest RC combination is the parallel RC circuit shown in the following circuit. The RC circuit can be used as a high pass filter or a low pass filter depending upon the component from which the output is derived for example the RC circuit acts as the high pass filter when the output is taken from the resistor and as the low pass filter when the output is taken from the capacitor.

parallel RC circuit

series RC circuit

 

The series RC circuit acts as the passive low pass or high pass filter the series combination of the resistor and capacitor is as shown in the following image. It is called passive as all the components employed in the filter are passive.

RC Time Constant,series RC circuit

Operation of the RC Circuit:

As pointed out earlier that the series combination of resistor and capacitor can be used as the low pass filter or a high pass filter before understanding the operation of the RC filter let us first consider the natural response of the parallel circuit. As we know that capacitor is one of the basic electrical components that is used to store electric charge when two leads of the capacitor are shorted the capacitor immediately discharges, and if the resistor is connected in parallel to the charged capacitor then it will discharge through the resistor and the time will be taken by the capacitor to completely discharges which depends upon the RC time constant.

RC Time Constant:

The RC time constant of the RC circuit is the product of the resistance and the capacitance and it is the time required by the capacitor to charge through the resistor to about 63.2 percent of its initial value and similarly the time required by the capacitor to discharge through the resistor to 36.8 percent of its initial value.

RC Time Constant

 

Applications of RC Circuit:

Resistor-Capacitor combination is commonly used in filters some of the applications of the RC circuit are listed in the following:

  • RC circuit is used as the low pass filter.
  • RC circuit can also be used as the high pass filter.
  • RC circuit can be used in feedback network of the op amp based circuit.
  • RC circuit can also be used in the signal shaping circuits.
  • RC circuit is used in delay lines.
  • RC circuit is used in relaxation oscillator.

Introduction to RC Circuit:

 

I hope this article would be helpful for you, in this article I have discussed the basics of the RC combination. That is all for now in the next article I will come up with more interesting topics in engineering till then stay connected, keep reading and enjoy learning.