HI,
I have come to the problem attached and have been given the answer from the text book but not sure how to calculate hie.
The question asked for a value of input resistance of the circuit.
The formula I am using is
\( Rie= R1//R2//(hie+hfeRe)\)
where
\(hie =\frac{0.026}{Ibq}\)
So
\( = 18k//180k//(hie+(560\times200)\)
Now Ibq is the bais current which I need but an unsure which numbers to use in the figure.
Do I have to find out the current between the 180k and 18k resistors?
Thanks for your time
I have come to the problem attached and have been given the answer from the text book but not sure how to calculate hie.
The question asked for a value of input resistance of the circuit.
The formula I am using is
\( Rie= R1//R2//(hie+hfeRe)\)
where
\(hie =\frac{0.026}{Ibq}\)
So
\( = 18k//180k//(hie+(560\times200)\)
Now Ibq is the bais current which I need but an unsure which numbers to use in the figure.
Do I have to find out the current between the 180k and 18k resistors?
Thanks for your time
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