Cascode电流镜有没有提高电路PSRR的作用？

jianyungsun

回复 17# fuyibin


   can you give us more  details？

jianyungsun

回复 19# icdane


   我想问一下你说的电容分压是具体是怎么回事？

fuyibin

   

回复  fuyibin
你说的对，其实我想表达，在低频的时候，一般都可以做到足够低，意义不大。所以，比如ca ...
icdane 发表于 2014-7-18 11:42

                               
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in low power supply, it is very difficult to improve psrr. if your design is in 1V power domain, there is no enough headroom.

semico_ljj

testing

icdane

回复 23# fuyibin if really headroom limited, i do not see much difference between these two. while i would put more cap as load.

icdane

回复 24# semico_ljj

and assign more head room to the current source instead of adding a cascoding in the linear

fuyibin

   

回复  fuyibin  if really headroom limited, i do not see much difference between these two. while i w ...
icdane 发表于 2014-7-20 00:51

                               
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if give you 100mV headroom, you can use larger channel length or use  cascode structure. one is 2 times output impedance improvement. the other is 10  times.

icdane

回复 27# fuyibin
i do not see that much , anyway, this is design based, we always have options between these two

limaoze39520

都在瞎扯，不说问题的本质。

银河水晶

表示还是不明白