Fully-integrated PMOS-based charge pumps in standard CMOS process without high-voltage switches

In this paper, we present two new PMOS-based charge pumps which can be implemented in a standard 0.18-μm CMOS technology. In the proposed charge pumps, only low voltage transistors are needed as they always experience voltages no higher than VDD. The maximum output voltage is substantially increased and not limited by transistor gate-oxide and diffusion-to-substrate junction breakdown, without using a triple-well process. The proposed 2-stage charge pumps can reach a power conversion efficiency of 80% and a voltage conversion ratio of 98% in simulation.