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1. The problem statement, all variables and given/known data
Find input resistance of the ckt (see attached)
2. Relevant equations
3. The attempt at a solution
Q2 is diode connected, so I replaced Q2 with VBE resistance (rbe or r∏).
So, Rin is rbe1+(β+1)rbe2
But the answer is somewhat different, it's rbe1+ (β+1) (rbe21/gm2)
Where did 1/gm2 come from?
Find input resistance of the ckt (see attached)
2. Relevant equations
3. The attempt at a solution
Q2 is diode connected, so I replaced Q2 with VBE resistance (rbe or r∏).
So, Rin is rbe1+(β+1)rbe2
But the answer is somewhat different, it's rbe1+ (β+1) (rbe21/gm2)
Where did 1/gm2 come from?
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