Oscillator with Reduced Acceleration Sensitivity

Abstract

The invention relates to an oscillator comprising two resonators, the direction of the vector of acceleration sensitivity of at least one first resonator of the at least two resonators, said direction being relative to the mounting surface of said first oscillator, corresponding substantially to the reflected direction that is reflected by a mirror plane of the vector of acceleration sensitivity of at least one second resonator of the at least two resonators, said direction being relative to the mounting surface of said second oscillator. The invention also relates to an oscillator comprising two resonators, the oscillator comprising a resistor which is effectively connected in parallel with one of the resonators and the resistance value of which is less than a hundred times that of the series resonator resistance of the combined resonator at the desired resonant frequency.

I claim: 
     
         1 . An oscillator comprising
 an electronic circuit, supported by a substrate or several substrates coupled to one another, and configured to initiate and obtain periodic oscillations; and   a first resonator supported by at least one of the substrates and a second resonator supported by at least one of the substrates, wherein the first and second resonators are operatively coupled to the electronic circuit and function as a combined resonator, in order to control a frequency of the periodic oscillations to achieve a desired resonance frequency, and the combined resonator has a series resonance resistance,   the oscillator exhibits an effective parasitic capacitance or parasitic resonance that occurs between an inter-resonator connection point and another node of the electrical circuit,   characterized in that the oscillator comprises, effectively connected between the inter-resonator connection point and said another node of the electrical circuit,   a resistor, a resistance value of said resistor being less than one hundred times the series resonance resistance of the combined resonator at the desired resonance frequency   or   an inductor, an inductance of said inductor in combination with the effective parasitic capacitance forming a resonant circuit having a parallel resonance at or near the desired resonance frequency.   
     
     
         2 . Oscillator according to  claim 1 , characterized in that
 the oscillator comprises, effectively connected between the inter-resonator connection point and said another node of the electrical circuit,   a resistor, a resistance value of said resistor being less than one hundred times the series resonance resistance of the combined resonator at the desired resonance frequency.   
     
     
         3 . Oscillator according to  claim 1 , characterized in that
 the oscillator comprises, effectively connected between the inter-resonator connection point and said another node of the electrical circuit,   an inductor, an inductance of said inductor in combination with the effective parasitic capacitance forming a resonant circuit having a parallel resonance at or near the desired resonance frequency.   
     
     
         4 . Oscillator according to  claim 2 , characterized in that
 said resistance value of said resistor is at least by a factor of 2 above the series resonance resistance of the combined resonator at the desired resonance frequency.   
     
     
         5 . Oscillator according to  claim 2 , characterized in that
 said another node of the electronic circuit, to which the resistor is connected to, from at least one connection point between two resonators, is another connection point of one of said resonators, making the resistor being effectively connected in parallel to one of the resonators.   
     
     
         6 . Oscillator according to  claim 5 , characterized in that
 said resistance value of said resistor is at least by a factor of 2 above the series resonance resistance of the combined resonator at the desired resonance frequency.   
     
     
         7 . Oscillator according to  claim 3 , characterized in that
 said another node of the electronic circuit, to which the inductor is connected to, from at least one connection point between two resonators, is Ground.   
     
     
         8 . Oscillator according to  claim 1 , characterized in that
 the oscillator comprises, effectively connected between the inter-resonator connection point and said another node of the electrical circuit,   a resistor, a resistance value of said resistor being less than one hundred times the series resonance resistance of the combined resonator at the desired resonance frequency   and   an inductor, an inductance of said inductor in combination with the effective parasitic capacitance forming a resonant circuit having a parallel resonance at or near the desired resonance frequency.   
     
     
         9 . Oscillator according to  claim 8 , characterized in that
 said resistance value of said resistor is at least by a factor of 2 above the series resonance resistance of the combined resonator at the desired resonance frequency.   
     
     
         10 . Oscillator according to  claim 8 , characterized in that
 said another node of the electronic circuit, to which the resistor is connected to, from at least one connection point between two resonators, is another connection point of one of said resonators, making the resistor being effectively connected in parallel to one of the resonators.   
     
     
         11 . Oscillator according to  claim 10 , characterized in that
 said resistance value of said resistor is at least by a factor of 2 above the series resonance resistance of the combined resonator at the desired resonance frequency.   
     
     
         12 . Oscillator according to  claim 8 , characterized in that
 said another node of the electronic circuit, to which the inductor is connected to, from at least one connection point between two resonators, is Ground.   
     
     
         13 . Oscillator according to  claim 9 , characterized in that
 said another node of the electronic circuit, to which the inductor is connected to, from at least one connection point between two resonators, is Ground.   
     
     
         14 . Oscillator according to  claim 10 , characterized in that
 said another node of the electronic circuit, to which the inductor is connected to, from at least one connection point between two resonators, is Ground.   
     
     
         15 . Oscillator according to  claim 11 , characterized in that
 said another node of the electronic circuit, to which the inductor is connected to, from at least one connection point between two resonators, is Ground.   
     
     
         16 . Oscillator according to  claim 2 , characterized in that
 the resistance of said resistor has a value, which ensures that the damping of undesirable oscillation modes is increased to a greater extent than the damping of the desired oscillation mode.   
     
     
         17 . Oscillator according to  claim 5 , characterized in that
 the resistance of said resistor has a value, which ensures that the damping of undesirable oscillation modes is increased to a greater extent than the damping of the desired oscillation mode.   
     
     
         18 . Oscillator according to  claim 8 , characterized in that
 the resistance of said resistor has a value, which ensures that the damping of undesirable oscillation modes is increased to a greater extent than the damping of the desired oscillation mode.   
     
     
         19 . Oscillator according to  claim 12 , characterized in that
 the resistance of said resistor has a value, which ensures that the damping of undesirable oscillation modes is increased to a greater extent than the damping of the desired oscillation mode.   
     
     
         20 . Oscillator according to  claim 1 , characterized in that
 the distance of the desired resonance frequency from the series resonant frequency of the resonators is less than 10% of the distance of the parallel resonance of the resonators from their series resonant frequency.