Hi guys...
I'm back again with Electronics problems.
I'm trying to find the output voltage at R_Load in the attached circuit.
I have written a closed net loop equation including the Zener, Q2 and R2 as:
Vz  Vbe2 + I1*R1 = 0
I1 = (Vz + Vbe2) / R1 = 4.57 mA
From here I found V_R1 by:
V_R1 = I1*R1 = 4.57 V
Can I say that Vo = 2*V_R1 ??? I think I can but I'm not sure...
I also have another solution that gives me the same result but by the same reason, I'm not sure why we can do that, which is:
Vo = (Vz + Vbe2)*(1 + R2/R1)
Why can we say directly that Vo is a voltage divider at R1 and that the Q2 base branch has no influence on this calc?
I'm back again with Electronics problems.
I'm trying to find the output voltage at R_Load in the attached circuit.
I have written a closed net loop equation including the Zener, Q2 and R2 as:
Vz  Vbe2 + I1*R1 = 0
I1 = (Vz + Vbe2) / R1 = 4.57 mA
From here I found V_R1 by:
V_R1 = I1*R1 = 4.57 V
Can I say that Vo = 2*V_R1 ??? I think I can but I'm not sure...
I also have another solution that gives me the same result but by the same reason, I'm not sure why we can do that, which is:
Vo = (Vz + Vbe2)*(1 + R2/R1)
Why can we say directly that Vo is a voltage divider at R1 and that the Q2 base branch has no influence on this calc?
Attachments

27.8 KB Views: 15