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AD823 Open Loop Characteristics

Question asked by veerasamy on Jun 2, 2016
Latest reply on Jul 14, 2016 by harryh


I am performing Stability analysis for a circuit with AD823 Opamp. I was checking Open Loop Gain parameters of the OPAMP and I referred Figure 14 of the datasheet.

In the figure, the frequency response is plotted from 100Hz. It can be seen that the phase has already become 90 degree at 100Hz. Hence the main Pole has occurred below 100Hz. However the Gain curve starts reducing only after 250 Hz. Can you clarify on this contradiction?


I was also verifying the Open Loop Gain of the OPAMP in SPICE. I have attached the SPICE result. However it was not matching Figure -14. Can you share the following paramenters?


Open Loop Gain at DC

Unity Gain Bandwidth

Phase Margin at Unity Gain BW