doublets and its effect?

[pugongying]

The gain boosting method can increase output resistance
but it may cause doublets which would result in slow settling

I don't know what is doublets and why it could result in slow settling?

And is there any other circuit structure have the similar problem?

 

[isaacnewton]

doublet -> one pole & one zero

The amplifier in the gain boosting method will create a pole-zero doublet. And it will decrease the bandwidth of the circuit.

The gain boosting method can increase output resistance
but it may cause doublets which would result in slow settling

I don't know what is doublets and why it could result in slow settling?

And is there any other circuit structure have the similar problem?

 

[shaokang_w]

IEEE PAPER "Relationship between frequency response and and Settling Time of Opertional Amplifiers" will tell you what and how

 

[zhaoshibin]

IEEE PAPER "Relationship between frequency response and and Settling Time of Opertional Amplifiers" will tell you what and how

This Gray's artical is the best one to help you learn the effect of doublet,You can also
read "the gain-boosted technology",it can been taken as a practical example of doublet.

 

[xwcwc1234]

Hi shaokang_w,
Do you have this paper ? Can upload here ?

 

[williamy]

in baker'book, doublet does lower the settling time,

 

[nassim_el85]

Hi

This is the paper with the topic "Relationship between Frequency response and settling time of operational amplifies",
But I can't find the "gain-boosted technology" special documentation.

 

[husseinadel]

The gain boosting method can increase output resistance
but it may cause doublets which would result in slow settling

I don't know what is doublets and why it could result in slow settling?

And is there any other circuit structure have the similar problem?

if you mean pole zero doublet ; it results in 2 time constants , one normalized to their sum and other to their difference , and so if you use fourier , you will show that in time , they add such that the signal rises very sharp and settles in a very big time , in opamps i think they use pole zero tracking to avoid it ; see gray & meyer book or ken martin one