Aspects of the present disclosure provide a high voltage switch with a fast turn-off. An example power supply circuit generally includes a capacitive element for coupling to a power terminal of an amplifier, a first switch configured to be closed in a first mode and to be open in a second mode, a second switch coupled in series between the first switch and the capacitive element and configured to be closed in the first mode and to be open in the second mode, a first circuit coupled to the first switch and configured to charge the capacitive element and power the amplifier in the first mode, and a buffer circuit having an output coupled to a first node and configured to output a first voltage level greater than half of a second voltage level at a second node.