A charge pump circuit without gate-oxide overstress for standard CMOS technology and suitable for low-power applications

In the last years the gate-oxide overstress has become a great concern for CMOS circuits and even more so for circuits such as charge pumps. A new charge pump circuit that overcomes the gate-oxide overstress problem and has improved efficiency is proposed in this work. Simulations have shown that for 1¿A current load a four-stage structure of proposed circuit reaches efficiency of about 64%, what is almost three times the efficiency of previous solutions in the same conditions. The better efficiency makes this circuit more suitable for low-power applications. Measurements have shown that a four-stage structure of the new circuits yields a pumping efficiency of 98.12%.