I have done a sim with cascaded CE amps. I have been able to calc iRC2,
iRF1, iRL, ib2, ic2 and ie2 based on vout = 234.88 mV and RL = 10KΩ.

How would I calc ic2, ib2, ie2 etc?

Do design engineers actually bother to calculate all of the ac voltages and
currents?

I have attached what I think is the AC equivalent circuit but I am at a loss
as how to proceed from there.

John

 

Please give spice model of transistor 2N3904JP.

 

See

 

Please give spice model of transistor 2N3904JP.

Hi Bordodynov

The transistor is just the 2N3904 and I have set Bf = 100 just to have a very conservative dc gain.


.model 2N3904JP NPN(IS=1E-14 VAF=100 Bf=100 IKF=0.4 XTB=1.5 BR=4 CJC=4E-12 CJE=8E-12 RB=20 RC=0.1 RE=0.1 TR=250E-9 TF=350E-12 ITF=1 VTF=2 XTF=3 Vceo=40 Icrating=200m mfg=NXP)

John

 

What is going on here? Or maybe I have a deja vu?
https://forum.allaboutcircuits.com/threads/two-stage-negative-feedback.160312/

 

Nearly all your components have non-standard unobtainable (at realistic prices) values. Why?
Any circuit design should use easily obtained standard values and allow for typical manufacturing tolerances.

 

Hi Bordodynov

The transistor is just the 2N3904 and I have set Bf = 100 just to have a very conservative dc gain.


.model 2N3904JP NPN(IS=1E-14 VAF=100 Bf=100 IKF=0.4 XTB=1.5 BR=4 CJC=4E-12 CJE=8E-12 RB=20 RC=0.1 RE=0.1 TR=250E-9 TF=350E-12 ITF=1 VTF=2 XTF=3 Vceo=40 Icrating=200m mfg=NXP)

John

It wouldn't be a bad idea to write a string on the electronic circuitry field:
.model 2N3904JP ako: 2N3904 Bf=100
then everyone would be able to simulate your scheme and I wouldn't ask for a model

 

Nearly all your components have non-standard unobtainable (at realistic prices) values. Why?
Any circuit design should use easily obtained standard values and allow for typical manufacturing tolerances.

I realize that.

What is going on here? Or maybe I have a deja vu?
https://forum.allaboutcircuits.com/threads/two-stage-negative-feedback.160312/

What?

 

Sorry I even asked. Good Bye. Morons.