Electronic Help

Discussion in 'Homework Help' started by fastcharlie2, Oct 16, 2014.

1. fastcharlie2 Thread Starter New Member

Oct 16, 2014
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Trying to calculate AC Vout. I did the DC analysis but dont know where to start the AC.

2. b1u3sf4n09 Member

May 23, 2014
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Can you please show us what work you have done?

3. fastcharlie2 Thread Starter New Member

Oct 16, 2014
4
0
I took the capacitor as an open and did a KVL from the 2V sourece to the 1.2kohm.
-Vb+Vbe+Ie(100+1.2k)=0
Ie=(2-.70/(100+1.2k)=1mA
Ie is approximate to Ic, Ic=1mA
Then a KVL at the output
-10V+1k x Ic+Vout=0
Vout=9V

The only thing I know for AC analysis is re=25mV/Ie=25ohm

4. t_n_k AAC Fanatic!

Mar 6, 2009
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One would need to know the source frequency since there are frequency dependent components in series with the source.

5. fastcharlie2 Thread Starter New Member

Oct 16, 2014
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The frequency is from 1kHz to 100kHz. But I dont understand how to do the AC analysis of this circuit.

6. t_n_k AAC Fanatic!

Mar 6, 2009
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Are you able to draw the small signal AC equivalent circuit? This is essentially a grounded base configuration. How would you know that it is grounded base?

7. fastcharlie2 Thread Starter New Member

Oct 16, 2014
4
0

I got it like this for the AC small signal but what do I got to do next?