What does the gain bandwidth product of an opamp tell us?
My understanding of it is this : It is basically the product of open-loop open-circuit voltage gain in V/V and the frequency at which the gain is measure on the -20dB/decade line . Also this value is identical to the unity gain bandwidth.
What I don't understand is what insight this value gives to the closed loop feedback operation of the opamp. Does it give some upper limit on speed of the circuit, in loose terms ?( I understand that it must but I can't seem to understand how to derive a transient response relationship in closed loop) Any help is appreciated ( or links to relevant material ).