IEEE Transactions on Circuits and Systems I Fundamental Theory and Applications · 2007 · 114 citations · 20 references
EngineeringComputer EngineeringElectrical EngineeringAnalog ElectronicsLow-power DesignSensorsAnalog Integrated CircuitsCapacitive SensingElectrical SensorsPressure SensorsSensor IntegrationSensor InterfacingAnalog-to-digital ConversionCapacitive SensorsLow-power Cmos DesignLow-power Sensor InterfacesSensor Interface CircuitsSensor Interface DesignSwitched-capacitor CircuitsUltra-low-power Cmos
Traditionally, most of the sensor interfaces must be tailored towards a specific application. This approach results in a high recurrent design cost and time to market. On the other hand, generic sensor interface design reduces the costs and offers a handy solution for multisensor applications. This paper presents a generic sensor interface chip (GSIC), which can read out a broad range of capacitive sensors. It contains capacitance-to-voltage converters, a switched-capacitor amplifier, an analog-to-digital converter, oscillators, clock generation circuits and a reference circuit. The system combines a very low-power design with a smart energy management, which adapts the current consumption according to the accuracy and speed requirements of the application. The GSIC is used in a pressure and an acceleration monitoring system. The pressure monitoring system achieves a current drain of 2.3 muA for a 10-Hz sample frequency and an 8-bit accuracy. In the acceleration monitoring system, we measured a current of 3.3 muA for a sample frequency of 10 Hz and an accuracy of 9 bits
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Capacitive sensors: When and how to use them
Robert Puers · Sensors and Actuators A Physical · 1993 · 327 citations · Full text