An efficient clock scheme for low-voltage four-phase charge pumps

Abstract

A new four-phase clock scheme for the four-phase charge pumping circuits at very low supply voltages using 0.5 /spl mu/m double poly CMOS technology to generate high boosted voltages is presented. The boosted clocks are applied on the capacitors connected to the gates of the major pumping transistors. With the new clock generator, the charge pump can efficiently pump to 8 V using 10 stages at V/sub dd/=1 V by simulations and 4.7 V using 4 stages at V/sub dd/=1.5 V by measurements.