  This paper presents theoretical analysis of a MEMS electrostatic energy
harvester configured as the Bennet's doubler. Steady-state operation of the
doubler circuit can be approximated by a right-angled trapezoid Q-V cycle. A
similarity between voltage doubler and resistive-based charge-pump circuit is
highlighted. By taking electromechanical coupling into account, the analytical
solution of the saturation voltage is the first time derived, providing a
greater comprehension of the system performance and multi-parameter effects.
The theoretical approach is verified by results of circuit simulation for two
cases of mathematically idealized diode and of Schottky diode. Development of
the doubler/multiplier circuits that can further increase the saturation
voltage is investigated.
