IC_fly
Newbie level 4
I want to ask a question about GBW and BW.
I have a questions: If feedback coefficient β is 1 (buffer) for cases and input signal frequency for 1MHz ( ignored SR of problem), hope the precision of output signal is high (1 per thousand). So we should design loop gain as 1000 around at 1MHz for, however,we couldn’t simply design GBW as 1MHz (at 1MHz , loop gain only 1), eventually design out of amplifier put GBW far away from 1MHz(1GHz) . But build time is determined by the GBW,so someone tell me just GBW=1MHz is OK.
So there are two ways to design this op amp :
1.BW > 1MHz, DC Gain > 1000,
GBW > 1 GHz
2.GBW(loop gain) > 1 MHz
Who can tell me witch one is right?:x
I have a questions: If feedback coefficient β is 1 (buffer) for cases and input signal frequency for 1MHz ( ignored SR of problem), hope the precision of output signal is high (1 per thousand). So we should design loop gain as 1000 around at 1MHz for, however,we couldn’t simply design GBW as 1MHz (at 1MHz , loop gain only 1), eventually design out of amplifier put GBW far away from 1MHz(1GHz) . But build time is determined by the GBW,so someone tell me just GBW=1MHz is OK.
So there are two ways to design this op amp :
1.BW > 1MHz, DC Gain > 1000,
GBW > 1 GHz
2.GBW(loop gain) > 1 MHz
Who can tell me witch one is right?:x