I am asked to find an Ic value to make the output impedance value equal to 33kohms.
I have attached the circuit and the parameters given are:
Parameters: BF = 100, VBE = 0.7 V, VA = 88 V, VT = 25.8 mV.
Calculate IC to make the output impedance equal to 33 kOhm
After making a small signal model of the circuit it seems to me that
gm = Ic/Vt; r(pi) = VT/Ib; and then that means ro = ABS(VA)/Ic...
I feel I am doing something wrong here because if the answer is really that easy I have spent way too much time on this problem. Some acknowledgment that I did it right or at least a push in the right direction would be wonderful.
Also I know the second transistor is acting like a diode but I am not quite sure how it would effect the current which in turn would effect the output impedance.
Please Help
I have attached the circuit and the parameters given are:
Parameters: BF = 100, VBE = 0.7 V, VA = 88 V, VT = 25.8 mV.
Calculate IC to make the output impedance equal to 33 kOhm
After making a small signal model of the circuit it seems to me that
gm = Ic/Vt; r(pi) = VT/Ib; and then that means ro = ABS(VA)/Ic...
I feel I am doing something wrong here because if the answer is really that easy I have spent way too much time on this problem. Some acknowledgment that I did it right or at least a push in the right direction would be wonderful.
Also I know the second transistor is acting like a diode but I am not quite sure how it would effect the current which in turn would effect the output impedance.
Please Help
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