High-side NMOS power switch and bootstrap driver for high-frequency fully-integrated converters with enhanced efficiency

This paper proposes a High-Side (HS) NMOS power switch and bootstrap driver with DCM charging phase extension for high-frequency fully-integrated converters with 1.2V supply voltage. The conventional bootstrap diode is replaced by a self-synchronized switch and the efficiency loss and operation failure at DCM is prevented by an extra charging phase. Simulation at 100MHz with UMC 0.13μm process shows that the optimum efficiency is driven 2% higher with significant power loss reduction by the proposed design compared to a conventional converter under similar operation conditions. 20% power stage area is saved by the dual NMOS structure compared to the conventional converter with PMOS and NMOS switches.