Confusing yet simple looking problem - DC analysis of diode & xstr

AI Thread Summary
The discussion revolves around a DC analysis problem involving a diode and a transistor, where the user is struggling to find the correct bias point. The user initially calculated a negative base current, indicating a mistake in their approach. Key hints suggest determining the emitter voltage when the Zener diode is on and reassessing the placement of the 0.7V drop in the circuit. It is emphasized that equivalent circuits should not be used for DC analysis, as they are meant for small signal variations. Understanding the correct assumptions and circuit configuration is crucial for solving the problem accurately.
Cetullah
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Homework Statement


DC analysis is required for the question in attachment.
Vz=6V
B=100
Vbe=0.7V


Homework Equations





The Attempt at a Solution


I tried to find the result using the currents that were defined by the transistor. I found a result that was nonsense, the base current Ib was negative, which is impossible.
Given in the attachment too.

Note: I have an exam tomorrow people. Would be awesome if you have guided me. Thanks :))
 

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It is impossible to tell what you did wrong if you do not show your work...
 
Don't use an equivalent circuit for dc analysis. Equiv. ckts. are for small variations about the bias point. Your job is to find the bias point.

Hints:
what must be the emitter voltage if the zener is on?
so then what must be the emitter current?
so then what is the collector voltage?
was your assumption that the zener is on, valid? why?
 
See where you have placed the 0.7 V voltage drop. Shouldn't it be in 2kilo-ohm resistor branch? Shouldn't there be a short where you have placed the 0.7 volt drop in the above diagram? See this and you can solve.
 
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