51.1.1. Introduction to Numerical Examples

Welcome to this NPTEL online certification course of Analog Electronic Circuits. Myself Pradip Mandal from E & EC department of IIT Kharagpur. We are continuing this course for quite some time and today’s topic of discussion it is Common Base Common Gate Amplifiers. In fact, this is continuation of our previous lecture. So, we already have discussed about the theoretical aspect, today we will go with more Numerical Examples.

In this first chunk, the lecturer introduces the course and the focus of the current lesson, which is the Common Base and Common Gate Amplifiers. He emphasizes that this is a continuation of previous discussions, linking theoretical concepts to practical numerical examples. This is important because numerical examples help in applying theoretical knowledge in a practical context.

Think of this section like a chef introducing a cooking class where they will not only talk about the ingredients (theory) but will also begin to cook (numerical examples) using those ingredients to make a dish (amplifiers).

So, our plan is to cover the following items of this topic. As I said that we already have discussed about the motivation of going for this common base and common gate configuration. We also have discussed about the basic operation and biasing of these two configurations and also we have talked about small signal analysis for different performance parameters, namely voltage gain input impedance, output impedance and current gain.

Here, the professor outlines the structure of the lesson. He mentions that they will discuss motivation, basic operation, biasing, and performance parameters (like voltage gain, input impedance, output impedance, and current gain) related to common base and common gate configurations. This clear plan helps students understand what to expect and how the lesson will build upon prior knowledge.

Consider this plan like a roadmap for a road trip. Each stop along the way (motivation, operation, biasing) illustrates different aspects of the journey's overall objective—understanding amplifiers.

Today we will be covering number of numerical examples associated with these 2 basic configurations and whatever the expression we have obtained in the previous class of different parameters that will be extensively used here and we will get numerical value of those parameters.

In this part, the professor states that numerical examples will be utilized to apply the previously learned expressions and theoretical concepts. This practical approach allows students to calculate actual values for parameters such as voltage gain and impedance, bridging the gap between theory and application.

Imagine learning to solve math problems using formulas (theory) and then applying those formulas to calculate your budget for a vacation (numerical examples). The actual calculations make the theoretical knowledge more meaningful and applicable.

Once we are comfortable on this numerical examples, then we will be in a position to discuss about what may be the design guidelines for a given requirement of the circuit performance.

This segment emphasizes the progression from working through numerical examples to the eventual goal of formulating design guidelines based on performance requirements. Understanding these guidelines will help students design efficient circuits that meet specific criteria.

Just as an architect follows specific building codes and guidelines after completing a design concept, electrical engineers use design guidelines to ensure their amplifiers function correctly in real-world scenarios.

So, let us go to the numerical example of common base amplifier. What we do have here it is the basic circuit given here and you can see that we do have ideal bias as well as more practical bias of the collector terminal...

The lesson shifts focus to a concrete numerical example involving a common base amplifier circuit. This segment details the circuit setup, including ideal and practical biasing techniques and the role of various components such as resistors and capacitors. It exemplifies how theoretical knowledge is applied to a real circuit scenario, including component values and their functions.

Think of this example like constructing a model car. Here, the parts (resistors, capacitors) play different roles. You must understand how each part fits together to ensure the model functions as intended.

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