| In this paper, it aims to improve characteristics of the monolithic-ally integrated 3. 3V/1. 2V switchechcapacitor (SC) DC-DC converter. By computer-aided tools, those including the topological structure of the conversion circuit, circuit devices, fabrication technology, and the dielectric material used in integrated capacitors are completely analyzed and optimized so as to search for effective approaches to improving the characteristics. Converters switched by CMOS switches rather than NMOS or PMOS ones have been studied in detail and fabricated as some sample dies by CMOS technology. In a single conversion circuit unit switched by CMOS switches, the test result indicates that the output current can arrive at 9.8mA a bit less than the simulation result of 12mA. To improve the output current further, two circuit units connected in a mutually compensatory manner of the improved converter are simulated with a doubled output current in comparison with a single circuit unit.The mathematical and circuit analyses of the converter show that the output current of the DC-DC converter tends to be saturated with the gradually increasing product of the operation frequency and the capacitor capacitance in the case of a determinate effective loop resistance. A voltage regulator mainly composed of a comparator is added to the main conversion circuit to stabilize the output voltage. Using Tspice simulation software, it is obtained that the output voltage of the converter with this regulator has a reduced ripple of less than 0. 8%and almost has nothing to do with the varied load resistance of more than 800 . Furthermore, on the basis of adopting PZT (Lead Zirconium Titanate) as the switched-capacitor dielectric, the output current of a single circuit unit is eight times as large as that of the former single circuit unit with identical technology process parameters.
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