ee484
Full Member level 3
Hi, all..
I have a simple and basic question...
Say I am designing a twe-stage ota. The first stage is for gain and the second stage is for output swing - for example, the first stage is telescopic ota and the second one is a common-source amplifier.
The small-signal gain of the first stage is 1000 and the second stage is 20.
I am wondering...if the input of the first stage is 50mV, internally the output of the first stage is then 5V???(say Vdd is 3V) - even though this two-stage ota is used in feedback system so that it has closed-loop gain of 2.
Why is this high gain stage (the first stage) not a problem???
I think I am confused with small signal and large signal concept.
Could anyone explain clearly??
The other question I have is my friend told me in 2 stage OTA with compensation, I have to crosswiring for compensation network (Cc and Rc). Do you know what that means? I think it is totally dependent on topology.
Thanks in advance
I th
I have a simple and basic question...
Say I am designing a twe-stage ota. The first stage is for gain and the second stage is for output swing - for example, the first stage is telescopic ota and the second one is a common-source amplifier.
The small-signal gain of the first stage is 1000 and the second stage is 20.
I am wondering...if the input of the first stage is 50mV, internally the output of the first stage is then 5V???(say Vdd is 3V) - even though this two-stage ota is used in feedback system so that it has closed-loop gain of 2.
Why is this high gain stage (the first stage) not a problem???
I think I am confused with small signal and large signal concept.
Could anyone explain clearly??
The other question I have is my friend told me in 2 stage OTA with compensation, I have to crosswiring for compensation network (Cc and Rc). Do you know what that means? I think it is totally dependent on topology.
Thanks in advance
I th