Circuit for detecting dynamic weak capacitance of MEMS device

A technology of weak capacitance and detection circuit, applied in the direction of measuring resistance/reactance/impedance, instruments, measuring devices, etc., can solve the problems of high-precision testing, high-frequency dynamic capacitance, static capacitance measurement principle and complex structure, and achieve the effect of reducing performance requirements

Active Publication Date: 2011-06-29
JIANGSU XINTONGDA ELECTRONICS SCI & TECHCO
View PDF5 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] The technology of the present invention solves the problem: Aiming at the shortcomings of traditional detection methods, a new type of dynamic weak capacitance detection circuit for MEMS devices is proposed, which provides a solution for low-cost and port...

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Circuit for detecting dynamic weak capacitance of MEMS device
  • Circuit for detecting dynamic weak capacitance of MEMS device
  • Circuit for detecting dynamic weak capacitance of MEMS device

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0022] Such as figure 1 As shown, the present invention is made up of driving signal generating circuit 1, C / V conversion unit 2, primary sample and hold unit 3, secondary sample and hold unit 4 and signal processing unit 5; C / V conversion unit 2 includes C / V conversion 21 and instrumentation amplifier 22; the primary sample and hold unit 3 includes a primary sample and hold circuit 31, a 90° phase shift network 32 and a primary sample and hold voltage comparator 33; the secondary sample and hold unit 4 includes a secondary sample and hold circuit 41 , an inverter 42 and a secondary sample-and-hold voltage comparator 43 .

[0023]The driving signal generation circuit 1 self-oscillates to generate a sinusoidal excitation signal with a frequency of 200KHz and an amplitude of plus or minus 8V. The sinusoidal excitation signal is loaded to the input end of the C / V conversion circuit 21, and under the action of the sinusoidal excitation carrier signal, the C / V conversion circuit 2...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a circuit for detecting dynamic weak capacitance of a micro electro mechanical system (MEMS) device, which is mainly applied to change detection of dynamic weak capacitance in a capacitive MEMS device. The circuit comprises a driving signal generation circuit, a capacitance to voltage (C/V) converting unit, a primary sampling and holding unit, a secondary sampling and holding unit and a signal processing unit. The driving signal generation circuit performs self-oscillation to generate a sine wave signal with fixed amplitude and frequency, and provides a detection pumping signal for the C/V converting unit; the C/V converting unit converts the weak capacitance variation into voltage, and a sine wave signal which can be processed by the subsequent stage of a samplingand holding circuit is output by an instrument amplifier; and the primary sampling and holding unit detects a positive peak point of the input sine wave, and when the positive peak point is detected,the output signal keeps the voltage of the positive peak point and half sine wave cycle is kept unchanged, the latter half cycle changes along with the input signal, and the output signal is used as a signal to be detected of the secondary sampling and holding unit.

Description

technical field [0001] The invention relates to a dynamic weak capacitance detection circuit of MEMS devices, which belongs to the field of weak signal detection in MEMS devices. Background technique [0002] MEMS devices have been widely used in the fields of industry, information, aerospace, and national defense because of their small size, long life, low energy consumption, easy integration, and low cost. [0003] According to different detection methods, MEMS devices can be divided into piezoresistive, piezoelectric, capacitive, thermocouple, optical fiber, electromagnetic, etc. Among them, piezoresistive, piezoelectric and capacitive are the current mainstream directions , and capacitive MEMS devices have been widely used because of their outstanding advantages such as large measurement range, high sensitivity, fast dynamic response, and good stability, and have become the research focus of major companies and scientific research institutions at home and abroad. [000...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01R27/26
Inventor 郭占社曹乐樊尚春李晶
Owner JIANGSU XINTONGDA ELECTRONICS SCI & TECHCO
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap