DC Circuit on the left, complete circuit in the middle and AC circuit on the right.
DC Circuit
Rs = 10k
R1 = 20k
RE = 5.1k
Beta = 300
VCC = 10V
==> VB = VCC*(R1/(R1+R1)) = VCC/2 = 5V
==> VE = VB - VBE = 5V - 0.7V = 4.3V
==> IE = VE/RE = 4.3V/5.1k = 843uA
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AC Circuit
R1b = R1/2 = 20k/2 = 10k
RL = 10k
Rs = 10k
gm = IE/VT = 843uA/25mV = 33.7mA/V
Vs = 1V
==> Re = VT/IE = 25mV/843uA = 29.66Ohm
==> Req1 = R1b||R1b||Beta*Re = 10k||10k||300*29.66 = 3.2k
==> Req2 = R1b||R1b||RE||RL = 10k||10k||5.1k||10k = 2.02k
==> -Vs + Is*Rs + Is*Req1 + Is*Req2*(1 + gm*Req1) = 0
==> Is = Vs/(Rs + Req1 + Req2*(1 + gm*Req1) = 1V/(10k + 3.2k + 2.02k*(1 + 33.7mA/V*3.2k) = 4.29uA
==> Vo = Is*Req2*(1 + gm*Req1) = 4.29uA*2.02k*(1 + 33.7mA/V*3.2k) = 0.943V
Simulation Vo = (Vmax + |Vmin|)/2 = (0.928V+ 0.942)/2 = 0.935V
Calculated Vo = 0.943V
Done
