Why the feedback speed is slower than the main signal path?

[surianova]

feedback feed

Hi !

Just want to ask why the speed of feedback path is normally slower than the
main signal path? Let say the main signal path is 3G, but the feedback path in the
range of few MHz is good enough? My personal opinion is with the lower speed in the feedback, it will give more accurate result. Any other opinion?

 

[hrkhari]

Re: feedback feed

Hi Surianova:

How do you justify the speed of a signal path?. Is it in propotional to the delay time of the circuitry? . Thank You

Rgds

 

[surianova]

Re: feedback feed

Hari ,
Let say the signal path have a diffrential amp with bandwidth 3G and and a feedback single-ended output amplifier ard 3 MHz for common mode fedback purpose to adjust bias tail for the diffrential amp. Is the single-ended output amplifier bandwidth very critical?

 

[leo_o2]

Re: feedback feed

I think it up to your applications.