SBIR Phase I: Isolator with MEMS piezoelectric transformer

This Small Business Innovation Research (SBIR) Phase I project will result in a novel isolator technology for power electronics and communications systems using the principle of ultrasonic transmission. Optocouplers and magnetic transformers are widely used to fulfill galvanic isolation between different parts of electrical circuits. However, issues with low transmission rates, narrow bandwidths and bulky sizes have motivated the investigation of alternative means to achieve isolation. The goal of the project is to develop a micro size isolator combining piezoelectric transformer technology with thin film processes. The new device will allow a wide transmission bandwidth range of 20kHz ~ 20MHz in a compact size of <1 mm3. Resonance modes, overshoots, and ringing control of the device during operation will be investigated and resolved through the proposed research to provide stable output with minimized noise. The final goal of the project is the development of an on-chip isolator for feedback signal control in network system and power supply applications. The developed technology will be provided to the existing isolator industry as a next generation device. The broader impact/commercial potential of this project is to provide a MEMS scale isolator to the electronic device industry which is more compact and efficient compared to existing optocoupler and magnetic isolators. According to market research reports, the optocoupler market has already reached the half-billion dollar level and grew over US $700 million in 2008. The optocoupler market can be divided up into various segments but the industrial segment is the main market with 60% of the demand being for motor control and related power needs. Communications is a broad market and power over Ethernet is a new market. Recently there were some interesting successes with plasma panel displays - each panel has many optocoupler inside due to the high voltage requirements. In data processing and computers there is a general need for optocouplers at the interface peripherals such as printers etc. These various demands will facilitate commercialization of the proposed product. Furthermore, MEMS scale of the suggested component can provide a breakthrough for miniaturization of mobile devices and slim designs for consumer products, such as wireless devices including laptop computers and communication devices.