Multi-Capacitor Pressure Sensor with Variable Gaps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional pressure sensors have limited measuring range and precision due to the distance between electrode plates, requiring either high voltage for large distances or narrow oscillation range for small distances.
Innovation Solution
The pressure sensor design incorporates multiple capacitors with varying gap distances between electrode plates, allowing superimposed capacitance changes to increase measuring accuracy and range, and includes a substrate with a MOS circuit and sealing rings for enhanced performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the distance between electrode plates is increased, then the measuring range is widened, but the measuring precision deteriorates
Solution Approach 1:
The patent divides the single capacitor into multiple capacitors (first capacitor, second capacitor, third capacitor) with different gap distances between electrode plates. Each capacitor provides a different sensitivity characteristic, allowing the system to achieve both wide measuring range and high precision by combining the outputs of multiple capacitors with varying gap sizes.
Solution Approach 2:
Different regions of the sensor structure have different gap distances between electrode plates. The first capacitor has a first gap distance, the second capacitor has a second gap distance, and the third capacitor has a third gap distance, creating local variations in sensitivity to optimize both measuring range and precision across different pressure ranges.
2Measurement precision
If the distance between electrode plates is decreased, then the measuring precision is improved, but the oscillation range is narrowed
Solution Approach 1:
The oscillator is divided into multiple capacitive sections (first, second, and third capacitors) with different gap distances. This segmentation allows each section to contribute to the overall oscillation range while maintaining precision, as the varying gap distances create different electrostatic forces that drive oscillation across a broader range.
Solution Approach 2:
The oscillator structure incorporates local variations in gap distance between electrode plates in different capacitor sections, creating different electrostatic actuation characteristics in each region to achieve extended oscillation range while maintaining precision.
3Device complexity
If a single capacitor is used, then the device complexity is reduced, but the measuring accuracy deteriorates
Solution Approach 1:
The patent merges multiple capacitors (first, second, and third capacitors) into a single integrated sensor structure, combining their capacitance changes to achieve higher measuring accuracy. The control and reading circuit integrates signals from all three capacitors to calculate pressure values, improving accuracy while managing complexity through unified design.
Solution Approach 2:
The sensor structure serves multiple functions simultaneously: it acts as a pressure sensor with high accuracy, an oscillator with extended range, and an ultrasonic wave sensor. The multiple capacitors provide both measurement and actuation capabilities, reducing the need for separate components and overall device complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design enhances measuring accuracy and range by calculating pressure values from multiple capacitance values and allows operation under both high and low voltages, improving the sensor's operational flexibility.
Implementation Method 1
The capacitive pressure sensor may work to measure pressure by changing capacitance between a top electrode plate and a bottom electrode plate using pressure
Implementation Method 2
By alternately applying a forward or reverse voltage to the movable electrode plate and the fixed electrode plate, the movable electrode plate may oscillate close to or away from the fixed electrode plate
Implementation Method 3
By alternately applying a forward or reverse voltage to the movable electrode plate and the fixed electrode plate, the movable electrode plate may oscillate close to or away from the fixed electrode plate
Implementation Method 4
an oscillator, an ultrasonic wave sensor and a measuring method thereof with hypersensitivity
Data Source
AI summary
The present invention relates to a pressure sensor, which may include a first electrode plate, a second electrode plate, a third electrode plate, a fourth electrode plate and a fifth electrode plate, which are successively laminated on a substrate, wherein the first electrode plate, the third electrode plate and the fourth electrode plate are fixed to the substrate, the first electrode plate and the second electrode plate are disposed opposite to each other and have a gap formed therebetween, the second electrode plate is suspended over the first electrode plate to constitute a first capacitor; the second electrode plate and the third electrode plate are disposed opposite to each other and have a gap formed therebetween, to constitute a second capacitor; and the fifth electrode plate is suspended over the fourth electrode plate to constitute a third capacitor, and can move along a direction perpendicular to the substrate.