Patent
Capacitance detecting circuit
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TLDR
A capacitance detecting circuit which can ensure flexibility in application without restriction imposed by a capacitance arrangement such as a single capacitance, differential capacitance or electrostatic servo and like arrangements, to a great advantage includes an operational amplifier having an inverting input terminal and an output terminal between which a feedback capacitance component is connected.Abstract:
A capacitance detecting circuit which can ensure flexibility in application without restriction imposed by a capacitance arrangement such as a single capacitance, differential capacitance, differential capacitance electrostatic servo and like arrangements, to a great advantage includes an operational amplifier having an inverting input terminal and an output terminal between which a feedback capacitance component is connected, a capacitance sensor having an electrostatic capacitance subjected to change under action of an external force, a switch for electrically charging the capacitance component of the capacitance sensor by connecting a charge/discharge terminal of the capacitance component to a reference voltage at a first clock timing for discharging the feedback capacitance component and switching the charge/discharge terminal to the feedback capacitance component at a second clock timing to transfer electric charge, and a sample-and-hold circuit for converting the transferred electric charge to the sensor output voltage.read more
Citations
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References
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Journal ArticleDOI
Switched-capacitor circuit design
TL;DR: Circuit design techniques are described for switched-capacitor filters, modulators, rectifiers, detectors, and oscillators for telecommunications, speech processing, and other signal-processing systems.
Patent
Capacitance-type electrostatic servo acceleration sensor
TL;DR: In this paper, a capacitance-type electrostatic servo acceleration sensor capable of detecting applied acceleration with high sensitivity and with low error without needing an accurate oscillator is presented. But the sensor is not equipped with a capacitive sensor.
Patent
Interface circuit for capacitive sensor
TL;DR: In this article, an interface circuit for a capacitive sensor capable of outputting a detection signal with high stability and reliability while suppressing to a minimum the influence of offset and temperature dependency onto the output signal is presented.
Patent
Circuit arrangement having a differential capacitor arrangement exposed to mechanical detuning
Hans-Juergen Prof Dr Gevatter,Ying Dipl Ing Yu,Henning Dipl Ing Gaus,Hartmut Dipl Phys Dr Grethen +3 more
TL;DR: In this article, the authors proposed a circuit arrangement for the measurement of acceleration, in which two high-frequency voltages having phases mutually shifted by 180@ are applied to a differential capacitor arrangement, and an electrical measuring signal proportional to the acceleration is generated by evaluation of the high-voltages; this is fed via summing amplifiers to the capacitor arrangement for compensating for the mechanical detuning.
Patent
Variable capacitor sensor for acceleration or pressure monitor
TL;DR: In this paper, a sensor whose output signal is dependent on changes in electrical capacity is used for measuring the relevant physical parameters in e.g. acceleration or pressure responsive detectors, and the detector itself comprises the three switches (1,3,5), the capacitors (4,6), amplifier (7), and the variable sensing capacitor (2) whose capactive changes result in an analogue output voltage.