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amplifiers

These amplifiers tutorials cover a wide range of basic amplifiers topics for your electronics learning. It is strongly suggested you start out with small signal amplifiers because this is where all the basics of amplifiers begins. You will receive a further understanding of transistors and how they operate in amplifiers.


AMPLIFIERS

THIS ELECTRONICS TUTORIALS SITE

It is assumed you have completed all of the tutorials on basic electronics because without that basic grounding you will go nowhere here. It is assumed you have a good understanding of ohms law to be able to follow the necessary calculations here.

SMALL SIGNAL AMPLIFIERS

These amplifiers tutorials cover a wide range of basic amplifiers topics for your electronics learning. It is strongly suggested you start out with small signal amplifiers because this is where all the basics of amplifiers begins. You will receive a further understanding of transistors and how they operate.

What are small signal amplifiers? An amplifier, with or without negative feedback, having the greatest fidelity in faithfully reproducing the input with the least distortion. It is however the least efficient, in as much the power delivered to the load is only a small percentage of the d.c. power used up in the amplification process.

BROAD BAND AMPLIFIERS

Electronics tutorials on further amplifier design topics are broadband amplifiers which include audio amplifiers, then there are the versatile buffer amplifiers, low level rf amplifiers are of course covered and this includes linear amplifiers.

Broad band amplifiers are amplifiers which will reproduce a wide range of signals without significant loss throughout the pass band. A typical broad band amplifier is a mast head amplifier erected on a TV mast and designed not only to amplify VHF and UHF TV signals but also to establish a low noise figure. Not all broad band amplifiers are that wide so we will consider some examples here.

BUFFER AMPLIFIERS

A buffer amplifier is designed to follow low level stages. This will then present a sufficiently high enough input impedance so it is not considered a significant load to that stage. The intermediate or buffer amplifier stage, while not representing a load must then have a sufficiently low output impedance to drive successive stages

AMPLIFIERS USING EMITTER DEGENERATION

We also discuss amplifiers using emitter degeneration which is very handy for both enhanced stability and defined impedances.

Emitter degeneration in an amplifier can be described as when all or part of an emitter resistor is not bypassed for ac or rf. Emitter degeneration is an important property in stable amplifier design.

AMPLIFIERS USING NEGATIVE FEEDBACK

Also there are amplifiers using negative feedback as a further aid to stability.

Negative feedback is often referred to as shunt feedback and here in this application we will use it in conjunction with emitter degeneration. How is this accomplished? Negative feedback or shunt feedback is accomplished by adding one resistor and a capacitor between collector and base of our transistor. For this exercise I'm going to go to an r.f. application and replace a resistor with a choke, it could easily have been a transformer.

TUNED CIRCUIT AMPLIFIERS

Tuned circuit amplifiers are amplifiers where the RFC or resistor load is replaced by a tuned circuit from our band pass filters or low pass filters and if amplifier filters tutorials.

FUTURE PLANNED AMPLIFIER TUTORIALS

In future planned electronics tutorials if there is sufficient feedback we will tackle car amplifiers because we believe this to be an area of great interest. Audio power amplifiers are another area of deep interest but as with so many products today increasing reliance is being made upon the use of integrated circuits for audio circuits as opposed to discrete transistors. Later we'll cover rf power amplifiers.

index | broad band amplifiers | buffer amplifiers | emitter degeneration | negative feedback
small signal amplifiers | tuned circuits amplifiers

 

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