Temperature insensitive silicon oscillator and precision voltage reference formed therefrom

A precision voltage reference having an inherent insensitivity to radiation, employing a micromechanical, silicon tuning fork gyroscope disposed on a glass substrate and having a proof mass translated by a force electrode and sensed by a sense electrode, said voltage reference comprising:

• a frequency generator proximate said gyroscope for providing a reference frequency;
• a voltage source proximate said gyroscope providing a voltage signal to said force electrode;
• and
• sense electronics proximate said gyroscope and in communication with said sense electrode for receiving a proof mass motion signal, for receiving said reference frequency from said frequency generator, and for generating a difference signal between said proof mass motion signal and said reference frequency,
• wherein said voltage source receives said difference signal and adjusts said voltage signal based thereupon, said voltage source providing said voltage signal as a voltage reference.

A micromechanical, thermally insensitive and radiation hard reference device fabricated from a micromechanical silicon-on-glass structure comprising:

• a substantially planar glass substrate;
• at least one silicon anchor disposed on said substrate;
• a plurality of silicon beams extending from said at least one anchor and parallel to said substrate;
• a first weighted element suspended from said plurality of beams above said substrate and relocatable along a first axis substantially orthogonal to said planar substrate;
• a force electrode disposed on said substrate, substantially beneath said first weighted element;
• a first electrical signal source in electrical communication with said force electrode for providing a first alternating potential between said force electrode and said first weighted element to cause said first weighted element to oscillate along said first axis;
• a sense electrode disposed proximate said force electrode on said substrate, substantially beneath said first weighted element;
• and
• a first frequency module proximate said reference device and receiving an electrical signal from said sense electrode reflective of capacitive fluctuations between said sense electrode and said first weighted element during relocation of said first weighted element along said first axis, said first frequency module providing a first measured frequency equivalent to the frequency of sensed capacitive fluctuations.

A micromechanical reference frequency device comprising:

• a substantially planar glass substrate;
• a micromechanical tuning fork gyroscope disposed on said substrate, said tuning fork comprising
• a plurality of silicon anchors disposed on said substrate,
• a plurality of silicon beams extending from said plurality of anchors, parallel to said substrate,
• first and second weighted elements each suspended from respective ones of said plurality of beams above said substrate, said weighted elements rotatable about a first axis parallel and above said substrate,
• at least one force electrode disposed on said substrate under each of said first and second weighted elements, and
• at least one sense electrode disposed on said substrate under each of said first and second weighted elements;
• a first source of electrical bias in communication with said force electrodes for establishing an alternating bias between each of said weighted elements and respective force electrodes for oscillating said weighted elements about said first axis;
• and
• a first frequency module in communication with said sense electrodes for determining a frequency of capacitive fluctuation between said weighted elements and respective sense electrodes during oscillation of said weighted elements about said first axis and for providing a first measured frequency reflective of said capacitive fluctuation.

A micromechanical reference voltage device comprising:

• a substantially planar glass substrate;
• a micromechanical tuning fork gyroscope disposed on said substrate, said tuning fork comprising
• a plurality of silicon anchors disposed on said substrate,
• a plurality of silicon beams extending from said plurality of anchors, parallel to said substrate,
• first and second weighted elements each suspended from respective ones of said plurality of beams above said substrate, said weighted elements rotatable about a first axis parallel and above said substrate,
• at least one force electrode disposed on said substrate under each of said first and second weighted elements, and
• at least one sense electrode disposed on said substrate under each of said first and second weighted elements;
• a first source of electrical bias in communication with said force electrodes for establishing an alternating bias between each of said weighted elements and respective force electrodes for oscillating said weighted elements about said first axis;
• a first frequency module in communication with said sense electrodes for determining a frequency of capacitive fluctuation between said weighted elements and respective sense electrodes during oscillation of said weighted elements about said first axis and for providing a first measured frequency reflective of said capacitive fluctuation;
• and
• a first frequency comparator for comparing said first measured frequency with a frequency standard and for providing said first source of electrical bias with a first feedback signal,
• wherein said first source of electrical bias provides a first bias standard.