airboss
Member level 3
Hi,
i have a question regarding using current mirrors to process signals. this is something razavi mentioned in his textbook. given a reference mos ckt with ideal current source Iref and (W/L)ref. the other mos ckt mirroring current from reference ckt is Ix and (W/L)x. so razavi says that if Iref increases by delta_I, then Ix increases by delta_I*((W/L)x)/((W/L)ref).
my question is, how do i generate the "small signal"? how do i generate the "delta_I"? it doesn't make sense to me that we generate a small current signal while the drain is connected to an ideal current source.
thanks for your patience and help.
i have a question regarding using current mirrors to process signals. this is something razavi mentioned in his textbook. given a reference mos ckt with ideal current source Iref and (W/L)ref. the other mos ckt mirroring current from reference ckt is Ix and (W/L)x. so razavi says that if Iref increases by delta_I, then Ix increases by delta_I*((W/L)x)/((W/L)ref).
my question is, how do i generate the "small signal"? how do i generate the "delta_I"? it doesn't make sense to me that we generate a small current signal while the drain is connected to an ideal current source.
thanks for your patience and help.