Question 12 An operational amplifier is fabricated using the 741 circuit but with different processing so that the transfer function before compensation has three negative real poles with magnitudes 30kHz, 500kHz and 1OMHz. Figure 12 shows the conceptual schematic diagram of this op- amp 938 Bias GA 2 24 TF KK Output HE ec va he 9 Figure ll Conceptual Schematic of Op-Amp 741 (a) In order to achieve a 45 phase margin in a unity-gain feedback connection, it has been suggested to compensate this op-amp by introducing a low-frequency dominant pole. If the low- frequency gain of this op-amp is 70dB, determine the value of this dominant pole frequency: *) the expected unity-gain cross-over frequency after com- pensation Question 12 An operational amplifier is fabricated using the 741 circuit but with different processing so that the transfer function before compensation has three negative real poles with magnitudes 30kHz, 500kHz and 1OMHz. Figure 12 shows the conceptual schematic diagram of this op- amp 938 Bias GA 2 24 TF KK Output HE ec va he 9 Figure ll Conceptual Schematic of Op-Amp 741 (a) In order to achieve a 45 phase margin in a unity-gain feedback connection, it has been suggested to compensate this op-amp by introducing a low-frequency dominant pole. If the low- frequency gain of this op-amp is 70dB, determine the value of this dominant pole frequency: *) the expected unity-gain cross-over frequency after com- pensation