How Accurate is My Solution for IC and VCE in a Silicon Transistor Circuit?

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This is for a 300 level electronics lab class and I'm wondering if I'm close:

Homework Statement



If the following silicon transistor (VBE = 0.6 V) has a B value of 100, determine IC and VCE.

Homework Equations



http://img862.imageshack.us/img862/80/circuit1.th.jpg

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The Attempt at a Solution



First I found an expression for \alpha (0.99) and noted that
VBC=VCE-0.6

Then I used Kirchoff's laws for the BE loop and the "loop" from the -15 V down to ground:

BE Loop:
-15 + 2000IC + VCE + 1000IE = 0
-15 + 2990IC + VCE = 0

15 V to Ground:
-15 + 40000IB +VBC + 2000IC = 0
-15.6 + 2400IC + VCE =0

I then solved these equations to get:
IC = 1 mA
VCE = 18.04 V

Any tips would be greatly appreciated.

Also, if anyone can recommend a good electronics text. Mine (Principles of Electronic Instrumentation by Diefenderfer) is filled with errors and is short on example problems.

Thanks,

MG

Homework Statement


Homework Equations


The Attempt at a Solution

 
Last edited by a moderator:
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It might be profitable to replace the base bias network with a Thevenin equivalent. Then the only loop you need to concentrate on will be the one containing the base-emitter.

Emitter current should be IE = IB(β + 1). Then, knowing VBE = -0.6V, you should have everything required to solve for IB, thence IC.
 

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