Position sensing circuit for an electrostatically driven MEMS device

Patent · Tue Nov 21 04:00:00 EST 2023

OSTI ID:2293877

Panas, Robert Matthew; Corral, Princess; Hunter, Steven L.; Paul, Phillip Harris

The present disclosure relates to a system for detecting movement of a microelectromechanical system (MEMS) device. The system uses a drive voltage signal source for generating a low frequency drive voltage signal for driving the MEMS device. An excitation signal source may be used for generating an excitation signal which is also applied to the MEMS device. The excitation signal has a frequency which is above a physical response capability of the MEMS device, such that operation of the MEMS device is not significantly affected by the excitation signal. A sensing impedance is used to help generate a signal which is responsive to the capacitance of the MEMS device. The capacitance of the MEMS device changes in response to movement of the MEMS device. An output subsystem is provided which responds to changes sensed by the sensing impedance, and which produces an output voltage signal. A filter filters the output voltage signal to produce a filtered output voltage signal. The filtered output voltage signal is indicative of a position of the MEMS device.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC52-07NA27344
• Assignee: Lawrence Livermore National Security, LLC (Livermore, CA)
• Patent Number(s): 11,820,649
• Application Number: 17/187,206
• OSTI ID: 2293877
• Country of Publication: United States
• Language: English