for the circuit shown , if i want to calculate gain of the second stage then do i need to consider the output resistance of first stage as the source resistance for the second stage ?
first stage is common collector and second is common base
and voltage gain for common base is
RO1 = re ll RE ll ro = .02513 KΩ
RS = Ro1
then gain equation will become AV2 = gm2(RC)(re2llRS) = 76.92
but in the solutions they have ignored the effect of RS and used AV2 = gm2(RC)
i.e they ignored the effect of stage 1 on stage 2 to find Vo2/Vo1 but have considered the effect of stage 2 on stage 1 to find Vo1/Vi
please clarify this
first stage is common collector and second is common base
and voltage gain for common base is
Av = (gm/RS)(RcllRL)(re ll RE ll RS)
If yes then the output resistance of first stage (Common collector) will be RO1 = re ll RE ll ro = .02513 KΩ
RS = Ro1
then gain equation will become AV2 = gm2(RC)(re2llRS) = 76.92
but in the solutions they have ignored the effect of RS and used AV2 = gm2(RC)
i.e they ignored the effect of stage 1 on stage 2 to find Vo2/Vo1 but have considered the effect of stage 2 on stage 1 to find Vo1/Vi
please clarify this
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