A charge pump without overstress for standard cmos process with improved current driver capability

Many charge pump structures that overcome gate-oxide overstress have been proposed in the last few years. Though they differ in the number of phases and in efficiency, they have almost the same current driver capability. A new charge pump without gate-oxide overstress, with a better current driver capability is proposed here. The new circuit is derived from a two-phase charge pump in order to inherit its efficiency. A four-stage structure of the proposed circuit has shown a driver current capability 40% better than the previous solutions. The proposed circuit is also faster than the previous charge pumps that overcome gate-oxide overstress.