Back to results
US 8,427,251 B2Granted
Temperature compensated oscillator including MEMS resonator for frequency control
AssigneeThe Regents of the University of California
InventorsEmmanuel P. Quevy, Roger T. Howe
Life of this patent
Estimating the term…
Abstract
Disclosed is an oscillator that relies on redundancy of similar resonators integrated on chip in order to fulfill the requirement of one single quartz resonator. The immediate benefit of that approach compared to quartz technology is the monolithic integration of the reference signal function, implying smaller devices as well as cost and power savings.
Claims17
A temperature sensor apparatus, comprising:
- a first oscillator having a first microelectromechanical resonator for establishing a first oscillation frequency, wherein said first oscillation frequency has a first temperature dependency;
- a second oscillator having a second microelectromechanical resonator for establishing a second oscillation frequency, wherein said second oscillation frequency has a second temperature dependency;
- wherein said first oscillator and said second oscillator have similar resonant frequencies and different temperature dependencies;
- and
- a mixer to generate a beat frequency from mixing said first frequency and said second frequency into a mixed output whose frequency provides a measure of temperature;
- wherein said difference in temperature dependency is in response to an expansion coefficient mismatch of oscillator and substrate materials which result in similar resonant frequencies yet different linear temperature coefficients of said first oscillator and said second oscillator.
3 more elements
A temperature sensor apparatus, comprising:
- a first oscillator having a first electromechanical resonator for establishing a first oscillation frequency, wherein said first oscillation frequency has a first temperature dependency;
- a second oscillator having a second microelectromechanical resonator for establishing a second oscillation frequency, wherein said second oscillation frequency has a second temperature dependency;
- wherein said second temperature dependency is different than said first temperature dependency;
- and
- an apparatus responsive to said first oscillation frequency and said second oscillation frequency for determining a frequency difference in said first frequency and said second frequency which is output as a measure of temperature;
- wherein said difference in temperature dependency is in response to an expansion coefficient mismatch of oscillator and substrate materials which result in similar resonant frequencies yet different linear temperature coefficients of said first oscillator and said second oscillator.
3 more elements
A temperature sensor apparatus, comprising:
- a first oscillator for establishing a first oscillation frequency, said first oscillator having a first temperature coefficient of frequency;
- a second oscillator for establishing a second oscillation frequency, said second oscillator having a second temperature coefficient of frequency;
- wherein said second temperature coefficient of frequency is different than said first temperature of coefficient of frequency;
- and
- means for mixing said first frequency and said second frequency;
- means for filtering the mix of said first frequency and said second frequency as a mixed signal;
- and
- means for counting said mixed signal as clocked by said first frequency to produce a count output as a measure of temperature;
- wherein said difference in temperature coefficient of frequency is in response to an expansion coefficient mismatch of oscillator and substrate materials which result in similar resonant frequencies yet different linear temperature coefficients of said first oscillator and said second oscillator.
6 more elements
Dependencies are inferred from the claim text.