Capacitive acceleration sensor (you will know the article)
of the acceleration sensor is a device capable of measuring acceleration forces, when an object is the acceleration forces during acceleration force on an object; such as gravity, when the vehicle acceleration forces, down elevator these are the time acceleration forces.
Modern science and technology required acceleration sensor applications in many fields such as: military, space systems, scientific measurement fields require the use of small size, light weight, stable performance of the acceleration sensor.
The acceleration sensor manufactured in a conventional processing methods is difficult to fully meet these requirements, then the application of new micro-accelerometer fabricated micromachining techniques emerged.
Such a sensor of small size, light weight, low power consumption, quick start, low cost, high reliability, easy to implement digital and intelligent. Since the micro-mechanical structure to make accurate and reproducible, easy integration, suitable for mass production, it accounts for its high cost performance in acceleration sensor market dominance.
The acceleration sensor according to the principle can be divided into several categories:
capacitive acceleration sensor
resistive acceleration sensor
of the piezoelectric type acceleration sensor
according to the different needs of applications corresponding to a scene work accelerometer.
Here To briefly about its structure generally capacitive acceleration sensor using a spring-mass system. When changing the gap between the mass and the mass and the fixed electrode capacitance variation thereby enabling movement by acceleration acts. Capacitive accelerometer having an acceleration sensor with high sensitivity as compared to other types of zero frequency response, good environmental adaptability, especially on a relatively small temperature dependency; but deficiencies manifested in the input and output signal is nonlinear , the range is limited, the influence of cable capacitance, and the capacitance sensor itself is a high impedance signal source, the output signal of the capacitive sensor often need to improve by a subsequent circuit. In practice more capacitive acceleration sensor used for low-frequency measurement, inferior to its versatility piezoelectric acceleration sensor, and the cost is much higher than the piezoelectric acceleration sensor.
