Hello.
I am having a bit of a Problem solving this task. I need to calculate Rin, Rout and the current gain Ai ("e" is in and "a" is out)
This is how I tried to solve it :
1)
Re = ReT = Ue/ie for Ua=0
Ue = ie*rbe+Re*(ie+ie*ß) solved for Ue/ie : Re = rbe + (1+ß)Re
2)
Ra = Ua/ia for Ue = 0
Ua = Re*(ube/rbe+ube/rbe*ß - Ua/rce+ia) for ube = -Ua/rbe
Ua = Re*(-Ua/rbe - Ua/rbe*ß - Ua/rce +ia) solved for Ua/ia = Re/(1+(1+ß)*Re/rbe+Re/rce)
3)
Ai = ia/ie for Ua=0
ie = ib
ia = Ua/Re - ib - ib*ß
ia/ie = -ib - ib*ß/ib = - ib*ß
I think 3) is obviously wrong since the current shouldnt be inverted...
I am having a bit of a Problem solving this task. I need to calculate Rin, Rout and the current gain Ai ("e" is in and "a" is out)
This is how I tried to solve it :
1)
Re = ReT = Ue/ie for Ua=0
Ue = ie*rbe+Re*(ie+ie*ß) solved for Ue/ie : Re = rbe + (1+ß)Re
2)
Ra = Ua/ia for Ue = 0
Ua = Re*(ube/rbe+ube/rbe*ß - Ua/rce+ia) for ube = -Ua/rbe
Ua = Re*(-Ua/rbe - Ua/rbe*ß - Ua/rce +ia) solved for Ua/ia = Re/(1+(1+ß)*Re/rbe+Re/rce)
3)
Ai = ia/ie for Ua=0
ie = ib
ia = Ua/Re - ib - ib*ß
ia/ie = -ib - ib*ß/ib = - ib*ß
I think 3) is obviously wrong since the current shouldnt be inverted...
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