64.2.2. Increasing Gain

In fact, cascode amplifier it is having two types of advantages; one is extending the bandwidth as we just now we have discussed particularly in present of significantly large value of the source resistance, the other advantage which is commonly used is that the increasing the gain drastically.

The cascode amplifier offers two main benefits. Firstly, it improves bandwidth performance, especially when there's a high source resistance. Secondly, and more commonly recognized, it significantly boosts the gain of the amplifier. These advantages highlight the effectiveness of cascode amplifiers in enhancing the overall performance of electronic circuits.

Think of a cascode amplifier like a multilayered cake. Each layer represents a stage that contributes to the overall flavor (gain) of the cake. Just as adding more layers enhances the cake's taste, using a cascode configuration enhances the amplifier's gain and bandwidth.

So, to get the higher gain so far whatever the example we have considered R it was only 2.8 k. So, the increasing the capability of the cascode amplifier to increase the gain, it has been blocked by the low value of this R.

In previous discussions, a resistance value of 2.8 kΩ limited the gain of the circuit. The low resistance restricts the potential of the cascode amplifier to boost the gain significantly. Hence, increasing this resistance ensures that the cascode amplifier can effectively expand its gain capabilities.

Imagine trying to water a large garden through a small hose. The hose limits how much water you can supply to the garden, similar to how a low resistance limits the gain of the amplifier. By using a wider hose (higher resistance), you can water the garden more effectively.

So, to demonstrate the capability of the cascode amplifier to increase the gain first of all let we consider a different situation instead of having this R if you put some active circuit there, probably then the advantage of the cascode amplifier particularly for enhancing the gain it will be quite prominent.

By surrounding our cascode amplifier with an active circuit instead of the usual R, we can better showcase its gain-enhancing capabilities. This configuration illustrates how replacing passive components with active ones can significantly improve performance.

This is akin to upgrading a bicycle to an electric bike. The electric bike can move faster and cover more distance than a standard bike, much like how an active circuit can enhance the gain compared to passive components.

On the other hand since we have do have 12 V supply here and if we are expecting this I BIAS it will be supplying the entire 2 mA of current; obviously, then drop across this resistance it will be quite high to avoid that problem we consider this I BIAS.

To effectively achieve practical gain within the circuit, we start with a 12V supply for the biasing current. The current set at 2 mA impacts how voltage drops across associated resistances, thus directly influencing circuit functionality. BIAS ensures that we're set up correctly to achieve our desired gain.

Imagine setting the perfect temperature for baking a cake. If the oven temperature is just right, the cake bakes beautifully; if not, it might turn out poorly. Similarly, having the right bias current establishes the ideal environment for the cascode amplifier to perform at its best.

So, this is roughly 300 Hz only yes. So, the advantage here what we got namely we got very high gain from this circuit which it was I think we already have said that 384615.

In this part of the analysis, the gains computed resulted in a major output value of 384615, illustrating the considerable amplification provided by the circuit. However, this impressive gain comes with implications for the circuit's operational frequency, highlighting trade-offs that occur in amplifier design.

Think of boosting sound through a speaker system. If you crank the volume up too high, you might get distortion. Similarly, achieving a high gain in circuitry can affect the signal's clarity and operational bandwidth.

So, the advantage here what we got namely we got very high gain from this circuit which it was I think we already have said that 384615. In fact, if I considered this attenuation this divided by 2.

While achieving a high gain of 384615 is noteworthy, it is essential to consider the attenuation factors that work alongside. The design decisions lead to potential limitations in terms of bandwidth and signal quality, emphasizing the need for balance in circuit design.

It’s like building a super-fast car. While speed is impressive, if the car doesn’t have good brakes or handling, it can become dangerous. Similarly, achieving high gain without considering other aspects may lead to poorer performance in real-world applications.

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