Jerome wrote on Jun 23rd, 2006, 12:06pm: Hello,
In general GBW=UGF. It is true for a system with a dominant pole and all other poles and zeros located well beyond GBW (or UGF). For example, it is the case for a simple Miller opamp (with PM>60deg).
If you have poles and zeros within the GBW, then the relation GBW=UGF does not hold.
I hope this helps, Jerome.
Yes, for a single pole Adc*f3dB=unity_gain*funity. This is true because a 20 dB/dec decrease means the gain is going down 10x for every 10x increase in frequency. So, a DC gain of 100 and pole at 10 Hz gives GBW=1000 and it also gives a gain of 1 at 1000 Hz, so UGF=1000.