Design and realization of autonomous power CMOS single phase inverter and rectifier for low power conditioning applications

This paper deals with the design, the realization and the characterization of an integrated converter for low voltage and low power, isolated applications (3.3 V, 1 W). It is based on the association of two generic silicon dies performing DC to AC and AC to DC operations. The power dies are designed in CMOS technology and operate at high frequency (1 MHz) and high efficiency. This high power density realization includes the power circuit and the control electronic. The integrated conversion structure can operate as an inverter or as a rectifier in a wide range of power flows and input voltages. Three important issues are addressed in this paper: design of the power part at high efficiency, reduced consumption of the control electronic and the gate drivers, and implementation with reduced parasitic behavior. The practical implementation and characterization are also addressed in a second part. First tests are carried out with packaged dies on PCB boards, in order to simplify the implementation. The efficiency of the inverter reaches up to 92% as a function of input voltage with these conditions. The second experimental investigation is a full DC to DC converter implemented with two CMOS power dies (one inverter and one rectifier) together with an HF transformer and an output LC filter. This article ends with the study of the packaging in order to minimize parasitics elements, such as resistances and inductances, which can be very harmful for the global efficiency of our micro-converter.