Load Line Analysis: Example #2 - A Beta Stabilized Common-Emitter Circuit (066e3)

[@WECB640]

Keep producing this outstanding content Ralph. There ARE people who have the desire to learn. Many thanks. 73

[@eie_for_you]

Thanks, man! 😀

[@W1RMD]

@@eie_for_you But it's going to take less than $2 in parts to do all of this!

[@eie_for_you]

@@W1RMD🙂

[@W1RMD]

Thanks for giving all of this knowledge. Take care.

[@eie_for_you]

You are very welcome! 🙂

[@andymouse]

Great work....cheers.

[@eie_for_you]

Thank you and you are welcome! 🙂

[@davidluther3955]

HOW DID YOU COME UP WITH THE VALUE FOR THE SWAMPING RESISTOR OR,WHAT RULE OF THUMB DID YOU USE?

[@eie_for_you]

I'm not familiar with the term "swamping resistor," but I assume you are referring to the upper emitter resistor.
I start with the standard method of determining the emitter resistor value to establish the DC operating point. This is Re(total).
The gain of a common-emitter amplifier with an emitter resistor is *approximately* equal to the collector resistor value divided by the emitter resistor value. So, I say, "I want a gain of 'g' and my collector resistor value is 'Rc', so my un-bypassed emitter resistor value needs to be Re(gain)=Rc/g.
This value is smaller than Re(total).
So Re(bypassed) = Re(bottom) = Re(total) - Re(gain). Re(gain) becomes the top, un-bypassed emitter resistor. Hope this makes sense. 🙂

[@davidluther3955]

​THANK YOU!ALL THE ACTIVE CIRCIUTS TEXTBOOKS I HAVE CALL IT A SWAMPING RESISTOR,BECAUSE IT IS SUPPOSE TO REDUCE THE BAD EFFECTS OF r'e.