A 21 V output charge pump circuit with appropriate well-bias supply technique in 0.18 μm Si CMOS

Most of MEMS (Micro Electro Mechanical Systems) actuators require high control voltage such as 20 V. One of the significant challenges for MEMS implementation on Si CMOS is that the control voltage exceeds pn-junction breakdown voltage. The present work proposes a charge pump circuit that can generate higher output voltage than the breakdown voltage by applying appropriate bias voltages to backgate and deep-N-well of N-MOSFETs. Measurements showed that the prototype can generate DC voltage of 21V in 0.18 μm Si CMOS with 11V and 15 V breakdown voltage of pn-junction.