The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 28, 2017
Filed:
Feb. 10, 2015
Murata Manufacturing Co., Ltd., Nagaokakyo-shi, Kyoto, JP;
Lasse Aaltonen, Espoo, FI;
MURATA MANUFACTURING CO., LTD., Nagaokakyo-Shi, Kyoto, JP;
Abstract
A drive circuit for a MEMS resonator can include closed loop means for detecting and amplifying a signal of the MEMS resonator, and means for feeding the detected and amplified signal as a feedback signal back to the MEMS resonator. The circuitry also comprises DC bias voltage means for generating for the MEMS resonator a first DC bias voltage, and a second DC bias voltage that is controlled according to measured amplitudes of the MEMS resonator, one of the DC bias voltages being summed into the feedback signal. The circuitry comprises also a start-up circuitry adapted to detect a start-up state, and in response to a detected start-up state change at last one of the DC bias voltages to a predefined level. The state of constant oscillation is achieved reliably and in short time.