MEMS capacitive sensors, such as pressure sensors, accelerometers and gyroscopes have been one of the most successful examples of microsystem technology. They are routinely used in many applications; the most important being automotive safety systems. These sensors are typically openloop and have low to medium performance specifications. Recently, there has been an emerging requirement for high...

In this paper modeling of capacitance and sensitivity for MEMS capacitive pressure sensor is presented. In capacitive sensor the sensitivity is proportional to deflection and capacitance changes versus pressure. Therefore first the diaphragm displacement, capacitance and sensitivity of sensor with square diaphragm have been modeled and then simulated using finite element method (FEM).  It can b...

This paper is focused on a novel design of stepped diaphragm for MEMS capacitive pressure sensor used in tire pressure monitoring system. The structure of sensor diaphragm plays a key role for determining the sensitivity of the sensor and the non-linearity of the output.First the structures of two capacitive pressure sensors with clamped square flatdiaphragms, with different thicknesses are inv...

In this work, a 3D capacitive coupling structure employing periodic pattern was used for application to miniaturized on-chip passive components on MMIC (Monolithic Microwave Integrated Circuit). Unlike conventional periodic structure, the characteristic impedance of the 3D capacitive coupling structure was hardly dependent on frequency. Using the 3D capacitive coupling structure, RF passive com...

Low noise position measurement is fundamental for space inertial sensors, and at present the capacitive position sensor is widely employed for space inertial sensors. The design for the possible suppression of the front-end electric noises for a capacitive sensor is presented. A prototype capacitive sensor with 2×10−6pF/Hz1/2 at frequency above 0.04 Hz is achieved and further improvements are d...

Capacitive biosensors belong to the group of affinity biosensors that operate by registering direct binding between the sensor surface and the target molecule. This type of biosensors measures the changes in dielectric properties and/or thickness of the dielectric layer at the electrolyte/electrode interface. Capacitive biosensors have so far been successfully used for detection of proteins, nu...

The analog electronics is a challenging subject for undergraduate students in electrical engineering, due to the complex combination of many previous subjects, such as linear circuit analysis, signal and system, linear control theory and some sort of mathematics. This paper presents the modeling, analysis and design of the operational amplifier, which is used as benchmark system for analog elec...

The effect of the humidity of the surrounding atmosphere on the characteristics of capacitive structures is a known problem for capacitive gas-pressure sensors. However, the use of a differential mode of operation can provide a good solution – only the manufacturing of the ceramic structures with the appropriate pairs of capacitive sensing elements remains a major challenge. In order to find a ...

This paper presents a resonant-based read-out circuit for capacitive pressure sensors. The proposed read-out circuit consists of an LC oscillator and a counter. The circuit detects the capacitance changes of a capacitive pressure sensor by means of frequency shifts from its nominal operation frequency. The proposed circuit is designed in 0.18μm CMOS with an estimated power consumption of 43.1mW...

corrective feedback (cf) and its different types have long absorbed many scholars and practitioners. as ellis (2009) mentioned some experimental studies need to be carefully designed to discover the relative effectiveness of each of these cf techniques. the goal of this qualitative study was to discover whether the employment of different cf strategies could bring about an attitudinal shift. to...