Multi-source power supply system using micro-photovoltaic devices combined with microwave antenna

This paper reports a new power supply system that uses light and microwave simultaneously, to supply high- and multiple-voltages for MEMS (Micro Electro Mechanical Systems). This energy conversion device has been newly developed by integrating micro-photovoltaic devices and microwave antenna that are designed to minimize the interference between them. The micro-photovoltaic devices can generate high voltages (up to 100 V), because a number of tiny thin-film photovoltaic cells are interconnected in series. On the other hand, large currents can be provided with low voltages when the microwave antenna is used. The characteristics of both the micro-photovoltaic devices and microwave antenna were evaluated simultaneously by light and microwave supply system. As a result, the maximum voltage and current for the micro-photovoltaic device were found to be 101 V and 88 /spl mu/A, respectively. The voltage and current for the microwave conversion device (microwave antenna+RF module) were found to be 4.5 V and 74 mA, respectively. Additionally, the high output voltages from the micro-photovoltaic devices could be stabilized by originally designed voltage-stabilizing circuits.