Patent classifications
H03B5/30
Adaptive microphonics noise cancellation
Systems and methods are provided for compensating for mechanical acceleration at a reference oscillator. A reference oscillator provides an oscillator output signal and an accelerometer on a same platform as the reference oscillator, such that mechanical acceleration at the reference oscillator is detected at the accelerometer to produce a measured acceleration. A filter assembly, having an associated set of filter weights, receives the measured acceleration from the accelerometer and provides a tuning control signal responsive to the measured acceleration to a frequency reference associated with the system. An adaptive weighting component receives the oscillator output signal of the reference oscillator and an external signal that is provided from a source external to the platform and adjusts the set of filter weights for the filter assembly based on a comparison of the external signal and the oscillator output signal.
Adaptive microphonics noise cancellation
Systems and methods are provided for compensating for mechanical acceleration at a reference oscillator. A reference oscillator provides an oscillator output signal and an accelerometer on a same platform as the reference oscillator, such that mechanical acceleration at the reference oscillator is detected at the accelerometer to produce a measured acceleration. A filter assembly, having an associated set of filter weights, receives the measured acceleration from the accelerometer and provides a tuning control signal responsive to the measured acceleration to a frequency reference associated with the system. An adaptive weighting component receives the oscillator output signal of the reference oscillator and an external signal that is provided from a source external to the platform and adjusts the set of filter weights for the filter assembly based on a comparison of the external signal and the oscillator output signal.
Adaptive microphonics noise cancellation
Systems and methods are provided for compensating for mechanical acceleration at a reference oscillator. A reference oscillator provides an oscillator output signal and an accelerometer on a same platform as the reference oscillator, such that mechanical acceleration at the reference oscillator is detected at the accelerometer to produce a measured acceleration. A filter assembly, having an associated set of filter weights, receives the measured acceleration from the accelerometer and provides a tuning control signal responsive to the measured acceleration to a frequency reference associated with the system. An adaptive weighting component receives the oscillator output signal of the reference oscillator and an external signal that is provided from a source external to the platform and adjusts the set of filter weights for the filter assembly based on a comparison of the external signal and the oscillator output signal.
Adaptive microphonics noise cancellation
Systems and methods are provided for compensating for mechanical acceleration at a reference oscillator. A reference oscillator provides an oscillator output signal and an accelerometer on a same platform as the reference oscillator, such that mechanical acceleration at the reference oscillator is detected at the accelerometer to produce a measured acceleration. A filter assembly, having an associated set of filter weights, receives the measured acceleration from the accelerometer and provides a tuning control signal responsive to the measured acceleration to a frequency reference associated with the system. An adaptive weighting component receives the oscillator output signal of the reference oscillator and an external signal that is provided from a source external to the platform and adjusts the set of filter weights for the filter assembly based on a comparison of the external signal and the oscillator output signal.
Temperature stable MEMS resonator
A resonant member of a MEMS resonator oscillates in a mechanical resonance mode that produces non-uniform regional stresses such that a first level of mechanical stress in a first region of the resonant member is higher than a second level of mechanical stress in a second region of the resonant member. A plurality of openings within a surface of the resonant member are disposed more densely within the first region than the second region and at least partly filled with a compensating material that reduces temperature dependence of the resonant frequency corresponding to the mechanical resonance mode.
Temperature stable MEMS resonator
A resonant member of a MEMS resonator oscillates in a mechanical resonance mode that produces non-uniform regional stresses such that a first level of mechanical stress in a first region of the resonant member is higher than a second level of mechanical stress in a second region of the resonant member. A plurality of openings within a surface of the resonant member are disposed more densely within the first region than the second region and at least partly filled with a compensating material that reduces temperature dependence of the resonant frequency corresponding to the mechanical resonance mode.
Capacitor-referenced temperature sensing
The temperature-dependent resistance of a MEMS structure is compared with an effective resistance of a switched CMOS capacitive element to implement a high performance temperature sensor.
Capacitor-referenced temperature sensing
The temperature-dependent resistance of a MEMS structure is compared with an effective resistance of a switched CMOS capacitive element to implement a high performance temperature sensor.
Microelectromechanical system resonator-based oscillator
A device includes a MEMS resonator and oscillator circuit coupled to the MEMS resonator. The circuit includes a first transistor having a first control terminal and first and second current terminals, and a second transistor having a second control terminal and third and fourth current terminals. The circuit includes a resonator coupling network configured to inductively couple MEMS resonator terminals to the first and third current terminals, and to couple the first and third current terminals. The circuit includes a control terminal coupling network configured to couple the first and second control terminals, and to reduce a voltage swing at the first and second control terminals relative to a voltage swing at the first and third current terminals. The circuit includes a second terminal coupling network configured to couple the second and fourth current terminals. A second terminal coupling network resonant frequency is approximately that of MEMS resonator.
Microelectromechanical system resonator-based oscillator
A device includes a MEMS resonator and oscillator circuit coupled to the MEMS resonator. The circuit includes a first transistor having a first control terminal and first and second current terminals, and a second transistor having a second control terminal and third and fourth current terminals. The circuit includes a resonator coupling network configured to inductively couple MEMS resonator terminals to the first and third current terminals, and to couple the first and third current terminals. The circuit includes a control terminal coupling network configured to couple the first and second control terminals, and to reduce a voltage swing at the first and second control terminals relative to a voltage swing at the first and third current terminals. The circuit includes a second terminal coupling network configured to couple the second and fourth current terminals. A second terminal coupling network resonant frequency is approximately that of MEMS resonator.