Noise Analysis and Suppression Methods for the Front-End Readout Circuit of a Microelectromechanical Systems...

Area of Science:

• Electrical Engineering
• Mechanical Engineering
• Sensor Technology

Background:

• Circuit noise critically impacts Micro-Electro-Mechanical Systems (MEMS) gyroscope performance.
• Identifying and mitigating noise in analog circuits is crucial as they are primary noise sources.
• This research focuses on optimizing the front-end readout circuit and implementing noise suppression techniques.

Purpose of the Study:

• To analyze noise contributors in MEMS gyroscope front-end readout circuits.
• To propose and derive noise equations for an improved readout circuit using T-resistor networks.
• To develop noise suppression strategies for critical detection and control circuits.

Main Methods:

• Theoretical noise analysis of the front-end readout circuit.
• Implementation of an improved readout circuit utilizing T-resistor networks.
• Noise analysis and optimization of inverting amplifiers, low-pass filters, and high-pass filters.
• Experimental verification using an inverting amplifier and measurement of gyroscope output noise before and after optimization.

Main Results:

• Output noise reduced from 60 μV/Hz^1/2 to 30 μV/Hz^1/2.
• Bias instability decreased from 3.8 deg/h to 1.38 deg/h.
• Angular Random Walk (ARW) improved from 0.035 deg/h^1/2 to 0.018 deg/h^1/2.

Conclusions:

• The proposed noise analysis and suppression methods are effective for MEMS gyroscopes.
• Circuit optimization significantly enhances gyroscope performance metrics.
• The T-resistor network-based readout circuit offers a viable solution for noise reduction.