Implementation of a logical inverter using RF MEMS switch technology

The RF MEMS switches technology have found many applications in the communications and radar fields. Apart of the obvious switch function there are many other building blocks based on RF MEMS, such as digital variable phase shifter and digital variable attenuator, that have drawn the attention due to the superior RF performance of the MEMS switches when compared to traditional semiconductor alternatives [1–2]. Nevertheless the MEMS technology present some drawbacks that makes their use less attractive. In this sense the high pull-in voltage needed is one of the main weakness. Since the digital phase shifter and attenuator need many control lines, the high pull-in voltage issue accentuates for these applications. In order to reduce the number of control lines required an integrated logical inverter is needed. This paper presents the design and experimental characterization of a MEMS logical inverter which is fully compatible with the RF MEMS technology used for phase shifter and attenuator design, and thus it is suitable for integration in this kind of circuits.