Design of a step-up 400 mW@ 40 V charge-pump for microrobotics applications in a 100 V-0.7 μm intelligent interface technology

A new full custom charge pump based on a mixed solution between a Dickson and a two-phase voltage doubler (TPVD) has been developed. This power sources a full microrobot system that is based on piezoelectric actuators. These actuators work with voltages up to 40 V. Then, the main objective is to develop a charge pump that has to be able to boost the output voltage to 40 V from a single battery of 5 V. The charge pump has to be able to supply a power of 0.4 W as a peak, and nominally 200 mW. To achieve a high voltage a solution based on switching DC-DC converters has not developed because of weight and size constraints that are defined for the microrobot system, and also regarding possible EMI problems. The voltage and current levels needed for this system, and the electrical characteristics of the high-voltage devices, makes the integrated design complex. Also, the area constrains and efficiency with these conditions make us to define a charge-pump source based on a two-phase solution to reach a first voltage gain instead of just Dickson charge pumps and then solve some breakdown problems in the third stage. In order to design the full power source a technology available from the Europractice services has been adopted. this option is an intelligent interface technology from AMI called i2T100. which has transistors able to withstand voltages up to 100 V.