Em Microelectronic-marin Sa

Karlsruher Institut Fur Technologie

Gottfried Wilhelm Leibniz Universitat Hannover

Sylvain Grosjean

Alexandre Deschildre

Michel Willemin

Christophe Entringer

Yonghong Tao

Jean-Michel Daga

Jérémy Schlachter

Hugues Blangy

Beat Pfefferli

Kevin Scott Buescher

James Harold Lauffenburger

Gil Afriat

Pinchas Novac

Lawrence Bieber

Luca Rossi

Antonio Martino Ponzetta

Juergen Caro

Francisco Ramos

Stefan Bräse

Lars Heinke

Christof WÖLL

Brian Moore

Alexander Knebel

Zhengbang Wang

Michel M Willemin

In a sensing device of a pointing device, like a mouse, said pointing device includes at least one light source configured to illuminate a surface, at least one first secondary photodetector, at least one second secondary photodetector, and at least one primary photodetector. Each individual storage element of photodetectors is weighted and compared such as to sense a displacement of the pointing device.

Sensing device of a displacement of a pointing device

In a method for sensing a displacement of a pointing device, like a mouse, said pointing device includes at least one light source configured to illuminate a surface, at least one first secondary photodetector, at least one second secondary photodetector, and at least one primary photodetector. Each individual value of the photodetectors is weighted and compared such as to sense said displacement of the pointing device.

Method for sensing a displacement of a pointing device

An embodiment of the invention relates to a method for sensing a displacement of a pointing device, like a mouse. The pointing device includes at least one light source configured to illuminate a surface, at least one first secondary photodetector, at least one second secondary photodetector and at least one primary photodetector. Each individual value of photodetectors is weighted and compared to sense the displacement of the pointing device by comparing a plurality of storage elements.

Method for comparing a plurality of storage elements

A temperature sensor arrangement (), including a bandgap voltage generator (), which is configured to provide an output voltage (V); at least one semiconductor junction () for temperature sensing, which is biased by a biasing current flowing through said semiconductor junction (); and at least one poly-resistor (R) which is connected between the output () of the bandgap voltage generator () and the semiconductor junction (), thereby providing said biasing current from the bandgap voltage generator () to the semiconductor junction ().

Flicker noise reduction in a temperature sensor arrangement

An electronic measuring device for measuring a physical parameter includes a differential analogue sensor formed from two capacitances&#x2014;an excitation circuit of the differential analogue sensor providing to the sensor two electrical excitation signals which are inverted&#x2014;a measuring circuit which generates an analogue electrical voltage which is a function determined from the value of the sensor, and a circuit for compensating for a possible offset of the sensor, which is formed from a compensation capacitance, which is excited by its own electrical excitation signal. The excitation circuit is arranged in order to be able to provide to an additional capacitance of the compensation circuit its own electrical excitation signal having a linear dependence on the absolute temperature with a determined proportionality factor in order to compensate for a drift in temperature of an electrical assembly of the measuring device comprising at least the compensation capacitance.

Electronic device for measuring a physical parameter

The present invention relates to an interface circuit for a capacitive accelerometer sensor for measuring an acceleration value sensed by the sensor. The interface circuit comprises a plurality of electrical switches and three programmable capacitors. Two of the programmable capacitors are arranged to implement gain trimming of the interface circuit, while one of the programmable capacitors is arranged to implement acceleration range selection.

Interface circuit for a capacitive accelerometer sensor

A capacitive accelerometer for measuring an acceleration value is provided, including a first and a second electrode; a third mobile electrode arranged therebetween, and forming with the first electrode a first capacitor, and with the second electrode a second capacitor, the third electrode being displaced when the accelerometer is subject to acceleration and generates a capacitance difference value transformable to electrical charges; a first and a second voltage source configured to selectively apply first and second voltages to the first and the second electrodes, respectively, and a third voltage to the third electrode, and to generate electrostatic forces acting on the third electrode, the first, second and/or third voltages applied during electrical charge transfers for collecting the electrical charges to measure the acceleration; and an electrostatic force compensator to compensate for missing electrostatic forces due to a modified charge transfer rate, a compensation amount dependent on the modified rate.

Capacitive accelerometer

The physical parameter measurement method is performed using an electronic circuit () with a resistive sensor (). The resistive sensor includes two resistors (R, R) mounted in series, whose connection node connected to a moving mass (M), is connected to a first input of an amplifier-comparator (). A second input of the amplifier-comparator receives a reference voltage. One output of the amplifier-comparator is connected to a logic unit (), which provides a digital output signal (OUT). A digital-to-analog converter () provides a measurement voltage (V), as a function of a digital signal provided by the logic unit, to the first resistor (R) in a first phase of a measurement cycle, whereas the second resistor (R) is polarized by a polarization voltage, and to the second resistor in a second phase, whereas the first resistor is polarized by a polarization voltage via a switching unit.

Method for measuring a physical parameter and electronic circuit for implementing the same

The physical parameter measurement method is performed using an electronic circuit () with a resistive sensor (). The resistive sensor includes two resistors (R, R) mounted in series, whose connection node connected to a moving mass (M), is connected to a first input of an amplifier-comparator (). A second input of the amplifier-comparator receives a reference voltage. One output of the amplifier-comparator is connected to a logic unit (), which provides a digital output signal (OUT). A digital-to-analogue converter () provides a measurement voltage (V), as a function of a digital signal provided by the logic unit, to the first resistor (R) in a first phase of a measurement cycle, whereas the second resistor (R) is polarized by a polarization voltage, and to the second resistor in a second phase, whereas the first resistor is polarized by a polarization voltage via a switching unit.

The electronic measurement circuit comprises a measurement sensor with two differential mounted capacitors each comprising a fixed electrode, and a common electrode arranged to move relative to the fixed capacitor electrode to alter the capacitive value when the physical parameter is measured. The circuit further comprises a first integrator unit connected to the common electrode for integrating charge received from the sensor, and comprising two integrators arranged to be connected alternately to the common electrode, a first comparator for comparing analogue output values from the first integrator unit, a second integrator unit for integrating charge received from the first integrator unit, a second comparator for comparing analogue output values from the second integrator unit, a switch circuit for switching different voltage values across the capacitors, and a feedback circuit for feeding a digital output signal from the first comparator to the switch circuit for controlling its operation, and an incremental calculation unit receiving digital output signals from the comparators and supplying a final digital output signal.

Electronic measurement circuit

The present invention concerns an electronic measurement circuit for measuring a physical parameter. The circuit comprises: a measurement sensor comprising two differential mounted capacitors each comprising a fixed electrode, and a common electrode, common to the two capacitors which is arranged to be movable relative to each fixed electrode of the two capacitors in order to alter the capacitive value of each capacitor when the physical parameter is measured. The circuit further comprises a first integrator unit connected to the common electrode for integrating charge received from the measurement sensor, and comprising two integrators arranged to be connected alternately to the common electrode; a second integrator unit connected to the first integrator unit for integrating charge received from the first integrator unit; a comparator for comparing analogue output values from the second integrator unit; a switch circuit connected to the measurement sensor for switching different voltage values across the two capacitors; and a feedback circuit for feeding a digital output signal of the comparator to the switch circuit for controlling the operation of the switch circuit.

The electronic circuit measures angular speed in a gyroscope, which includes a mass connected to a spring and a damping element, an actuation capacitor for actuating the mass and a detection capacitor for detecting motion of the mass. The electronic circuit includes a measurement resistor, which is connected to the moving mass and has a variation in resistive value equal to the oscillation frequency of the mass. The resistor is polarized to supply a measurement signal, which includes a carrier signal in phase with the oscillation of the mass and an angular speed signal phase shifted by &#x3c0;/2 relative to the carrier signal The measurement signal is supplied to an integration unit clocked by a clocking signal phase shifted by &#x3c0;/2 relative to the carrier signal and originating from the drive circuit. The angular speed signal is demodulated at the integration unit output.

Electronic circuit for measuring rotational speed in a MEMS gyroscope and method for actuating the circuit

The method is for measuring a physical parameter via an electronic circuit connected to a two differential capacitor sensor having two fixed electrodes and a common moving electrode. The circuit supplies first and second digital measuring signals. Each measuring cycle consists on biasing fixed electrodes by a first biasing and a second biasing reverse of the first biasing, alternated with biasing the electrodes by the measuring voltage based on first and second digital signals. Each conversion starts by a small step value added to or subtracted from each digital signal in each cycle. If the successive identical amplifier output states counted or counted down by a counter is higher than a threshold, a large step value is added to or subtracted from the digital signals in each cycle. Re-adaptation to the small step value occurs when a sign change is detected in the counter, until the conversion end.

Method of measuring a physical parameter and electronic interface circuit for a capacitive sensor for implementing the same

A physical parameter is measured via an electronic circuit connected to a two capacitor sensor. The circuit includes an amplifier connected to the common capacitor electrode, a logic unit for digital processing amplifier data and supplying a digital measuring signal, a digital-analog converter for supplying a measuring voltage based on the digital measuring signal, a switching unit for alternately supplying the measuring voltage to the first and second fixed capacitor electrodes, and a regulated voltage for negative biasing or a low voltage for positive biasing from a voltage supply source. A first phase consists in biasing the first fixed electrode with the measuring voltage from first binary word and reference voltage, and the second fixed electrode with low voltage, and a second phase consists in biasing the second fixed electrode with measuring voltage from second binary word, which is reverse of the first binary word, and the reference voltage.

A method for reducing the non-linearity effect of a digital-analog converter on an electronic interface circuit of a capacitive sensor. The electronic circuit includes an amplifier connected to the common electrode by a switching unit, a logic unit connected to the amplifier for supplying first and second digital measuring signals, and a digital-analog converter for supplying a measuring voltage to the electrodes. The method includes firstly biasing the capacitor electrodes by the measuring voltage, then biasing the fixed electrode of the first capacitor at a regulated voltage and the fixed electrode of the second capacitor at a low voltage, then biasing the capacitor electrodes by the measuring voltage, and finally biasing the fixed electrode of the first capacitor at a low voltage and the fixed electrode of the second capacitor at a regulated voltage.

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Les Fins, France

Sylvain Grosjean