#### jonnybgood

##### Full Member level 4

"

An amplifier has 80dB gain at low frequency; the first pole is at 1 KHz while the second pole is at 1Mhz

What is the loop gain?

Find the phase margin."

Is it possible to derive the loop gain and phase margin from the above information?

I think from the information one can consider the system as a low pass filter with a maximum dc gain of 80dB. Then there is a roll off of 20dB/ decade after the first pole and 40dB/ decade after the second one.

https://upload.wikimedia.org/wikipedia/commons/0/07/Two-pole_Bode_magnitude_plot.png

What is this type of amp/filter ? Is there a general circuit with a standard formula so I can simulate it and experiment with it?

What is its function ?