[SOLVED] how to omitt cmfb circuit?

[boot_strap]

cmfb

how to omitt cmfb circuit?

 

[Vamsi Mocherla]

Re: cmfb

Design two single ended circuits and use them in differential configuration.

 

[ppenday]

Re: cmfb

vamshi can u tell me which book gives more in depth details of cmfb.

 

[avinash]

Re: cmfb

dear vamsi ,i think,the method you suggested for avoiding the cmfb is not very up the the mark.beacuase the two different single ended o/ps are avalaible with a delay between them.

 

[rambus_ddr]

Re: cmfb

Analysis and Design of Analog Integrated Circuits (4th Edition)
Paul R. Gray, Paul J. Hurst, Stephen H. Lewis, Robert G. Meyer

vamshi can u tell me which book gives more in depth details of cmfb.

 

[APPLESTREE]

Re: cmfb

In David Johns and Ken Martin's book " analog integrated circuit design" there are some basic CMFB circuits.

 

[mqc_hn]

Re: cmfb

**broken link removed** think it can help you!

 

[Vamsi Mocherla]

Re: cmfb

Actually there are two techniques to realize differential outputs from single ended inputs. One thing is to get an amplifier and a unity gain amplifier in series. There will be delay issues in this case. You can use it if you are not doing filter design or using wideband frequencies. Or else there is also a parallel technique. Here, we feedforward the common mode level. Please refer to the attachment for some insight. I have implemented both the things with success in industry and in college. I am sure that it will work for you.

 

[edajason]

Re: cmfb

as long as you have to use differencial output, you have to define the cm output. Simply way to sense the cm output is using resistor divider and capacitor divider in parallel.

how to omitt cmfb circuit?