Nxp Usa, Inc.

Freescale Semiconductor,inc.

Joel Cameron Beckwith

Jerome Romain Enjalbert

Dejan Mijuskovic

Thierry Dominique Yves Cassagnes

Andrew C McNeil

Jun Tang

Jalal Ouaddah

A sensor system includes a transducer for sensing a physical stimulus along at least two orthogonal axes and an excitation circuit. The transducer includes a movable mass configured to react to the physical stimulus and multiple differential electrode pairs of electrodes. Each of the electrode pairs is configured to detect displacement of the movable mass along one of the orthogonal axes. The excitation circuit is connectable to the electrodes in various electrode connection configurations, with different polarity schemes, that enable excitation and sampling of each of the orthogonal axes during every sensing period. For each sensing period, a composite output signal is produced that includes the combined information sensed along each of the orthogonal axes. The individual sense signals for each orthogonal axis may be extracted from the composite output signals.

Inertial sensor sampling with combined sense axes

A system includes a capacitive transducer, an excitation circuit, and a measuring circuit. The excitation circuit is configured to excite the capacitive transducer and the measuring circuit measures an output signal from the capacitive transducer responsive to the excitation voltage. The excitation circuit includes a voltage source for providing a first voltage in response to receipt of a supply voltage, a voltage generator coupled to the voltage source for receiving the first voltage and generating a second voltage that is greater than the supply voltage, and a control circuit coupled to the voltage source and the voltage generator. The control circuit is configured to provide any of a system ground, the first voltage, and the second voltage to first and second terminals of the capacitive transducer, and particularly, being configured to apply the system ground and the second voltage in the form of two consecutive stimuli with opposite polarities.

Excitation circuit, system including excitation circuit and capacitive transducer, and method

A circuit comprises an amplifier, a first switch arranged between an amplifier input and an amplifier output, a first capacitor, a first resistor, a second switch, a third switch, a first converter coupled to the first amplifier output, a register storing a last digital value, a second converter converting the stored last digital value into a corresponding voltage value, and a control circuit. The control circuit charges the first capacitor to the corresponding voltage value by coupling a second converter output to a second capacitor terminal and switching on the first switch, or by coupling the second converter output to the first capacitor terminal and switching on the third switch; switches on the first switch and the second switch for providing the input voltage signal to the first capacitor; and switches on the third switch for determining a subsequent digital value of the converted output amplifier signal.

Filtered sampling circuit and a method of controlling a filtered sampling circuit

A low pass filter circuit includes an amplifier having a single-ended output. A first line and a second line are arranged to receive a differential signal. A first switch selectively connects the first line to a first input of the amplifier in a first cycle of operation having a first observation window. A second switch selectively connects the second line to a second input of the amplifier in a second cycle of operation having a second observation window that is at least partially coincident with the first observation window. A signal measuring stage that is supplied with a modulated input signal generates the differential signal. The signal measuring state has an input switch to reverse a polarity of the differential signal applied to the first and second lines of the low pass filter circuit.

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Tokyo, Japan

Joel Cameron Beckwith