Design of Capacitance to Voltage Converter for Capacitive Sensor Transducer

Abstract

Problem statement:The design of Capacitance to Voltage Converter (CVC) for capacitive sensor transducer was presented. The proposed design will reduce the size, power consumption and supply voltage of the circuit and can be used in high frequency band transducer. Approach: The design was implemented using the Operational amplifier (Op amp) and capacitive network. The circuit was simulated using the PSPICE model parameters based on standard 0.13 µm CMOS process. Results: The design was able to measure a wide range of capacitance variations for the capacitive transducer. The performance analysis of the design showed desirable performance parameters in terms of response, low power consumption and a linear output voltage within the wide range of capacitive transducer capacitance variation for the power supply voltage of 1.2 V was achieved. Conclusion/Recommendations: The output voltage of the circuit varied linearly with the variation of capacitive transducer capacitance variation. The improved converter was compact and robust for integration into capacitive measuring systems and suitable for use in environment that making use of higher frequency band.

A New Multi-Valued Logic Buffer and Inverter Using MOSFET Based Differential Amplifier

“…The operating voltage range in the provided amplifier is from -1.8V to 1.75V. In another reported work by Alam et al [19], linear interval size of the amplifier gain is not enough. The reported linear interval is a little over 1.5V.…”

“…In a research reported by Alam et al [19], a capacitance to voltage converter is presented. This circuit was simulated using PSPICE model parameters based on standard 0.13µm CMOS process.…”

“…The reported works in this area either did not cover the voltage range required in the reported decenary MVL circuit designs [20,21], or their gain was not linear enough [17][18][19].…”

“…Table 3 summarized the Open-loop characteristics of proposed MBDA. The comparison at 25 °C is given in Table 4 [17][18][19][20].…”

Design of Minimal Capacitance Detect Circuit for MEMS Capacitive Sensor

“…AC bridge has a very high accuracy, however, the circuit is very complex. Charge amplify circuit has a simpler construction, high resolution and low power consumption [5,6,7,8]. In this paper, a capacitance detect circuit based on charge amplifier circuit is designed, it can be used to detect static and variable capacitance.…”