Solve for Vo in Transistor Circuit

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Tekneek
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Homework Statement


So I am supposed to find Vo in this circuit. Given, Vb-Ve=0.7, ic=100ib, ie=ic+ib

The Attempt at a Solution


In order to solve for Vout i did KVL for the two loops:

Loop 1 (left side, clockwise):

Vb-Ve-ie(416)+2-ib(10*103)=0
0.7-ic(416)-ib(416)+2-ib(10*103)=0
0.7-ib(100)(416)-ib(416)+2-ib(10*103)=0
2.7-52016ib=0
ib=5.19*10-5A

ic=5.19mA
ie=ic+ib=5.2mA
Ve=ie(416)=2.18V (this one i am not sure)

Loop 2 (Right side, anti-clockwise)

10-ic(2*103)-Vo-Ve-ie(416)=0
Subbing in everything i get
Vo=4.7V

But the answer is supposed to be 5 Volts, i am not sure where i made a mistake.

Circuit schematic of an NPN transistor amplifier with a 2 V source and 10 kΩ base resistor, a 2 kΩ collector resistor fed by a 10 V supply, and a 416 Ω emitter resistor, with labelled nodes Vb, Vout, Ve and currents ib, ic and ie.
 
The 2V and the 0.7V in the left hand loop are in opposite directions, so they should subtract, not add, so you should get 1.3-52016*Ib=0.
 
Last edited:
phyzguy said:
The 2V and the 0.7V in the left hand loop are in opposite directions, so they should subtract, not add, so you should get 1.3-52016*Ib=0.

I still don't get the right answer, this time around i get 7.87
 
You've made another mistake in the right hand loop, but you don't really need that. With what I gave you, you should get Ib = 25μA. Ic = 100* Ib = 2.5 mA. Vout = 10.0 - 2.5mA * 2.0 kΩ = 5.0V