The dominant pole is created by the value of Comp and the Gm stage. Ic = Vout Cjw = Gm Vin Since the voltage gain is large, consider that the PMos gate voltage change is much smaller than the drain voltage change (Vout). The op amp Gm stage (transconductance) is connected tothe Pmos gate and the capacitor, but the current is dominated by the Comp. ( second order effect the Gate to drain and gate-channel capacitance)