A low power controller for a MEMS based energy converter

The trend in modern VLSI design towards low power DSP and sensing applications creates an opportunity for the development of self-powered systems based on harvesting ambient energy. Several different ambient sources have already been exploited. With advances in microelectromechanical (MEMS) technology, it is possible to implement a self powered system-on-a-chip with the MEMS device acting as the energy transducer in the form of a variable capacitor, with conversion controlled by employing low power digital control techniques. This thesis explores the design of such an energy converter. The theory behind the conversion process will be discussed, including the presentation of a mathematical model for the system. The design of a programmable delay line based digital controller and optimization of the accompanying complementary power switches is reviewed. Results from the fabricated controller are presented and discussed. The design of a self-locking controller, which is based on the present architecture, but uses a new energy feedback technique to phase lock to maximal energy transfer, is presented. Thesis Supervisor: Anantha Chandrakasan Title: Associate Professor of Electrical Engineering

[1]  Anantha P. Chandrakasan,et al.  Low Power Digital CMOS Design , 1995 .

[2]  Anantha Chandrakasan,et al.  Embedded power supply for low-power DSP , 1997, IEEE Trans. Very Large Scale Integr. Syst..

[3]  James K. Roberge,et al.  Operational Amplifiers: Theory and Practice , 1975 .

[4]  Naresh K. Sinha,et al.  Modern Control Systems , 1981, IEEE Transactions on Systems, Man, and Cybernetics.

[5]  Abram P. Dancy.  Power supplies for ultra low power applications , 1996 .

[6]  E. L. Hudson,et al.  A variable delay line PLL for CPU-coprocessor synchronization , 1988 .

[7]  Anantha P. Chandrakasan,et al.  Trends in low power digital signal processing , 1998, ISCAS '98. Proceedings of the 1998 IEEE International Symposium on Circuits and Systems (Cat. No.98CH36187).

[8]  Stephen C. Galea,et al.  Self-powered discrete time piezoelectric vibration damper , 1997, Smart Materials, Nano-, and Micro- Smart Systems.

[9]  Sau-Mou Wu,et al.  An ASIC for transponder for radio frequency identification system , 1996, Proceedings Ninth Annual IEEE International ASIC Conference and Exhibit.

[10]  Anantha Chandrakasan,et al.  A reconfigurable dual output low power digital PWM power converter , 1998, Proceedings. 1998 International Symposium on Low Power Electronics and Design (IEEE Cat. No.98TH8379).

[11]  George C. Verghese,et al.  Principles of power electronics , 1991 .

[12]  Rajeevan Amirtharajah,et al.  Self-powered signal processing using vibration-based power generation , 1998, IEEE J. Solid State Circuits.

[13]  Eric A. Vittoz.  Micropower IC , 1980, ESSCIRC 80: 6th European Solid State Circuits Conference.

[14]  Neil Weste,et al.  Principles of CMOS VLSI Design , 1985 .

[15]  V. von Kaenel,et al.  A 2.1 MHz Crystal Oscillator Time Base with a Current Consumption under 500 nA , 1996, ESSCIRC '96: Proceedings of the 22nd European Solid-State Circuits Conference.

[16]  G. Asada,et al.  Wireless integrated network sensors: Low power systems on a chip , 1998, Proceedings of the 24th European Solid-State Circuits Conference.