Hello,
I am a hobbyist and i have a problem with the bjt fixed bias circuit. Obviously i am going wrong somewhere, kindly help me rectify my problem.
I have attached the circuit.
Here are my calculations:
When AC input = 5v then
Ib = (Vcc 5v)/20k = 0.75mA
Considering β = 10(assumption for calculations sake)
Ic = 7.5 mA ; Ic *Rc = 7.5V and hence Vce = Vcc  (Ic*Rc) = 12.5v
When AC input = 5v then
Ib = (Vcc 5v)/20k = 1.25mA
Considering β = 10(assumption for calculations sake)
Ic = 12.5 mA ; Ic *Rc = 12.5V and hence Vce = Vcc  (Ic*Rc) = 7.5v
So when the input voltage decreases so does the voltage across Vce and vice versa, which indicates that there is no phase shift between i/p and o/p which is not possible since we know that there exist a 180 degrees phase shift bewteen input and output. PLease do correct me with my calculations
Regards
I am a hobbyist and i have a problem with the bjt fixed bias circuit. Obviously i am going wrong somewhere, kindly help me rectify my problem.
I have attached the circuit.
Here are my calculations:
When AC input = 5v then
Ib = (Vcc 5v)/20k = 0.75mA
Considering β = 10(assumption for calculations sake)
Ic = 7.5 mA ; Ic *Rc = 7.5V and hence Vce = Vcc  (Ic*Rc) = 12.5v
When AC input = 5v then
Ib = (Vcc 5v)/20k = 1.25mA
Considering β = 10(assumption for calculations sake)
Ic = 12.5 mA ; Ic *Rc = 12.5V and hence Vce = Vcc  (Ic*Rc) = 7.5v
So when the input voltage decreases so does the voltage across Vce and vice versa, which indicates that there is no phase shift between i/p and o/p which is not possible since we know that there exist a 180 degrees phase shift bewteen input and output. PLease do correct me with my calculations
Regards
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