Folded cascode comparator

[Tom_Sawyer]

folded cascode

Hi all,

How do I make a comparator using a folded cascode? Where to connect the possitive feedback?

Tom

 

[gevy]

folded cascode comparator

You explain more in detail what problem have?

 

[Tom_Sawyer]

folded cascode

I want to design a comparator with hysteresis using a folded cascode type. As I have to design different types of comparators with different hysteresis I need to know where to connect the possitive feedback to..


Or would you suggest using a different type of comparaor?

The reason why I want to choose this architecture: I want to use it in a auto zero environment. As I have an auto zero opamp available and the architecture is a folded cascode one.. I wanted to resuse as much as possible.

Tom

 

[markty]

folded cascode feedback

U may check Phillip Allen's book.

 

[gevy]

folded cascode comparator design

The positive feedback can be as inside and outside of the comparator.
The internal positive feedback can be made in loading of the first cascade of the comparator.

 

[rfic]

folded cascode hysteresis

YOU can check book by David Johns

 

[arsenal]

히스테리시스, folded cascode amp

use folded cascode as input and use positive feedback as the loading,

 

[kkoko]

what difference folded cascade and cascode

You can use for first stage folded cascpde op and a second stage withouth miler capacitor

 

[chinito]

cascode comparator

for high speed comparator, there are three stages:

1) Input Stage (in your case, folded amplifier)
2) Decision Stage (hysterisis with latch)
3) Output stage (CSDA Complementary Self Biased Differential Amp.)

Ofcourse, follow third stage with two inverters as buffers to give you clean digital output. Read P Ellen's stuff on his website www.aicdesign.org. thanks.

 

[layes2]

self biased folded cascode

comparator is openloop used
you need not feedback
just use it
the ICMR is the only important issue