a voltage regulator comprising a voltage-controlled charge pump for providing a boot voltage between first and second terminals thereof that varies within a range between a turn-on voltage of a high-side GaN transistor, and a safe voltage limit between a gate and a source thereof throughout an active time of said high-side GaN transistor; and

a high side driver having an input for receiving a high side drive signal, an output for coupling to said gate of said high-side GaN transistor, a power supply terminal coupled to said first terminal of said voltage regulator, and a ground terminal coupled to said second terminal of said voltage regulator,

wherein the voltage-controlled charge pump further regulates the boot voltage within the range during a non-overlapping time period after a low-side GaN transistor becomes non-conductive and before said high-side GaN transistor becomes conductive.