As mentioned in connection with the foldedcascode op amp of the phase shift x(HOR) is due to the capacitances C1 through C5, each of which sees a source resistance on the order of 1y(gm 1 gmb). (a) If...

As mentioned in connection with the foldedcascode op amp of the phase shift x(HOR) is due to the capacitances C1 through C5, each of which sees a source resistance on the order of 1y(gm 1 gmb). (a) If we make the simplifying assumption that the effect of all these roots can be modeled, at least in the vicinity of fx, with a single pole frequency f2, use the values of a0 and fb of Eq. (7.121) to fi nd the value f2 that will ensure the value of fx of Eq. (7.121b). (b) If we make the additional assumptions that the effect of C1 through C5 can be modeled with a single equivalent capacitance Ceq, and that the various source resistances can be modeled with the common value Req 5 1y(gm 1 gmb) > 1.5 kV, estimate Ceq. (c) Develop a relationship between Cc and Ceq in terms of gcm1, Req, C6, and m, where m is the desired phase margin for operation with 5 1. (d) Estimate the required value Cc for m 5 608. What is the corresponding GBP? (e) Repeat, but for m 5 758, compare with and comment.