Re: UGF and GBW
GBW is the product of the DC gain with the 3-dB bandwidth of the amplifier.
UGF is the frequency at which the gain of the amplifier is equal to unity.
It should be noted that UGF is equal to the GBW only at the case that the amplifier acts as a single pole amplifier before the UGF, i.e only one pole before the UGF and all higher order poles are at frequency higher than the UGF.
Also, for single-pole systems, the GBW is constant because the 3-dB BW increase by the loop gain, while the gain decreases by the same value.