A pulse width modulated audio signal is supplied to a driver input of the gate driver circuit 103 via a level shifter 111. Hence, a level shifted replica of this pulse width modulated audio signal is supplied to the gate of the NMOS power transistor 107 via the driver output 104 of the gate driver circuit 103. The prior art gate driver circuit 103 is placed in a traditional well-structure of a semiconductor substrate into which the class D output stage 100 is integrated. This traditional well-structure has a parasitic well capacitance (not shown) coupled from the well structure to the semiconductor substrate. The traditional well-structure must furthermore be tied to the highest DC voltage potential of the prior art gate driver circuit 103 as explained below which has the undesired effect that the parasitic well capacitance becomes coupled to the high DC voltage GVDD_FLOAT at the high side positive supply voltage port 106a. The formation of the parasitic well capacitance creates numerous problems with the stability of the regulated DC voltage and makes the presence of a relatively large, and therefore, external regulator capacitor Cext mandatory to mitigate the harmful effects of the parasitic well capacitance as explained below in additional detail with reference to