Hello there, I have an exam on tuesday that involves MOSFET & BJT amplifiers.

I already know the basic things of DC biasing and basic AC (small-signal) analysis. However, I sometimes struggle
with calculating things such as voltage / current gain, input impedance, output impedance and lower/upper frequency bound.
That's probably because I don't understand understand the inner workings of both MOSFETs and BJTs. I know there's a lot of
info online but I'd like to grab a book that has everything in place. Are there any books that give practical examples of common gate/source/drain - emitter/base/collector (all single-stage) amplifiers and have some theoretical explanation with them not just equations? Please, recommend me something.

Thank you!

 

Hello,

Have a look at the chapters 2 and 3 of this book:
https://archive.org/details/TheArtOfElectronics_201711

Bertus

 

Thank you for your suggestion, will browse through a few chapters tonight. I have a question I'd like to ask about an example and I'll post it here instead of opening a new thread since it's related.

Right now, I'm stuck at an example of stable - biasing a BJT transistor with two resistors. I'm supposed to find R1 and R2.
This is it:

This is how I'm trying to solve it by merging loop 2 and loop 4, however, when I do this, both terms containing thevenin resistance cancel out and I cannot solve for it. What am I doing wrong here?

 

Nevermind, figured it out.

 

Normally we are doing it this way:

Ic≈Ie ≈ (5V - 2.5V)/1.2kΩ = 2.083mA hence Ve ≈ 0.416V we have Vb = 1.117V and Ib ≈ 13.9μA we have

Let us assume that the voltage divider current is ten times larger than the base current we have:

R1 = (5V - 1.11V)/(11 *13.9μA) ≈ 25.4kΩ = 24kΩ
R2 = 1.117V/(10*13.9μA) ≈ 8.1kΩ

or

R2 = 10*Re = 2kΩ and
Id = 1.117V/2kΩ = 558.5μA

And R1 = (5V - 1.117V)/(13.9μA + 558.5μA ) = 6.8k

As you can see one proper solution do not exist.

Also, you should never use Vcb in your equations.