dominoeff
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hi :
i have a problem when i calculate the impedance of the differential pair.it's a pair of BJT inputs with a current source connect to their emitter.when i calculate the impedance , i should 'see' the connect point to be the ground or should i 'see' there is a a big Ro.In the first situation it would be Rin=r(pi) and in the second situation it would Rin=r(pi)+(1+beta)Ro. what is the right answer?
thank you !
i have a problem when i calculate the impedance of the differential pair.it's a pair of BJT inputs with a current source connect to their emitter.when i calculate the impedance , i should 'see' the connect point to be the ground or should i 'see' there is a a big Ro.In the first situation it would be Rin=r(pi) and in the second situation it would Rin=r(pi)+(1+beta)Ro. what is the right answer?
thank you !