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US5287036A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for acoustic wave inductance

Assignee: CTS Corp
•
Filing: 1992-03-02
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Granted: 1994-02-15
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Expires: 2012-03-02
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Abstract

Abstract An inductive element for impedance matching comprises an acoustic wave propagating substrate and an acoustic wave transducer coupled to the acoustic wave propagating substrate. The acoustic wave transducer has an effective length L eff such that Le eff ≧C 2 v a /f o k 2 , where C 2 is a numerical factor such that C 2 ≧2, v a represents an acoustic velocity, f o represents an acoustic wave transducer center frequency and k 2 denotes an acoustic wave propagating substrate electromechanical coupling coefficient. Reflecting elements are provided on the substrate in the principal acoustic propagation directions to form a resonant acoustic cavity. The device exhibits inductive impedance and high Q over a significant frequency range in small physical size.

Inventors

  • 👤 David Penunuri

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 07:39
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/02535; H03H9/02614; H03H9/02629

Claims Analysis

Total Claims: 37
Claim 1
Independent Claim 150 words
A method for realizing a microelectronic filter comprising steps of: providing an acoustic wave propagating substrate; coupling a first acoustic wave transducer to the acoustic wave propagating substrate to provide a microelectronic inductance, the first acoustic wave transducer having an effective length L eff wherein: L.sub.eff ≧C.sub.2 v.sub.a /f.sub.o k.sup.2, where C 2 is a numerical factor such that C 2 ≧2, v a represents an acoustic velocity, f o represents an acoustic wave transducer center frequency and k 2 denotes an acoustic wave propagating substrate electromechanical coupling coefficient; and disposing an acoustic wave filter on the acoustic wave propagating substrate, the acoustic wave filter including second and third acoustic wave transducers acoustically coupled to each other, the first acoustic wave transducer being electrically coupled to the second acoustic wave transducer and providing an electrical impedance match for the second acoustic wave transducer over at least a first frequency range.
Claim 2
Independent Claim 150 words
A method for realizing a microelectronic filter comprising steps of: providing an acoustic wave propagating substrate; coupling a first acoustic wave transducer to the acoustic wave propagating substrate to provide a microelectronic inductance, the first acoustic wave transducer having an effective length L eff wherein: L.sub.eff ≧C.sub.2 v.sub.a /f.sub.o k.sup.2, where C 2 is a numerical factor such that C 2 ≧2, v a represents an acoustic velocity, f o represents an acoustic wave transducer center frequency and k 2 denotes an acoustic wave propagating substrate electromechanical coupling coefficient; and disposing an acoustic wave filter on the acoustic wave propagating substrate, the acoustic wave filter including second and third acoustic wave transducers acoustically coupled to each other, the first acoustic wave transducer being electrically coupled to the second acoustic wave transducer and providing an electrical impedance match for the second acoustic wave transducer over at least a first frequency range.
Claim 3
Dependent Claim 46 words
A method as claimed in claim 1, further comprising a step of providing a first acoustic wave reflector disposed to a first side of the acoustic wave transducer in a propagation path of at least some of an acoustic wave emitted from the acoustic wave transducer.
Claim 4
Dependent Claim 46 words
A method as claimed in claim 2, further comprising a step of providing a second acoustic wave reflector disposed to a second side of the acoustic wave transducer in another propagation path of at least some of the acoustic wave emitted from the acoustic wave transducer.
Claim 5
Dependent Claim 39 words
A method as claimed in claim 3, wherein said steps of providing said first and second acoustic wave reflectors include steps of providing first and second acoustic wave reflectors comprising electrodes spaced an integral number of acoustic wavelengths apart.
Claim 6
Dependent Claim 35 words
A method as claimed in claim 1, wherein said step of coupling an acoustic wave transducer includes a step of coupling an acoustic wave transducer comprised of electrodes one-fourth of an acoustic wavelength in width.
Claim 7
Dependent Claim 38 words
A method as claimed in claim 3, wherein said steps of providing said first and second acoustic wave reflectors include steps of providing first and second acoustic wave reflectors comprising electrodes spaced one-half of an acoustic wavelength apart.
Claim 8
Dependent Claim 49 words
A method as claimed in claim 1, wherein said disposing step further includes a step of disposing the first acoustic wave filter in shunt with the second acoustic wave transducer to provide an electrical impedance match for the second acoustic wave transducer over at least a first frequency range.
Claim 9
Dependent Claim 49 words
A method as claimed in claim 1, wherein said disposing step further includes a step of disposing the first acoustic wave filter in series with the second acoustic wave transducer to provide an electrical impedance match for the second acoustic wave transducer over at least a first frequency range.
Claim 10
Independent Claim 115 words
A method for providing an acoustic wave filter having a predetermined electrical impedance using a microelectronic inductance, comprising steps of: providing a piezoelectric substrate; coupling a first acoustic wave transducer to the piezoelectric substrate to provide a microelectronic inductance, the acoustic wave transducer having a number of electrode pairs N greater than a numerical constant C 1 divided by a piezoelectric substrate electromechanical coupling coefficient, where C 1 is a numerical factor such that C 1 >2; coupling an acoustic wave filter to the piezoelectric substrate, the acoustic wave filter including at least a second acoustic wave transducer; and coupling the microelectronic inductance to the second acoustic wave transducer to provide a predetermined electrical impedance.
Claim 11
Independent Claim 115 words
A method for providing an acoustic wave filter having a predetermined electrical impedance using a microelectronic inductance, comprising steps of: providing a piezoelectric substrate; coupling a first acoustic wave transducer to the piezoelectric substrate to provide a microelectronic inductance, the acoustic wave transducer having a number of electrode pairs N greater than a numerical constant C 1 divided by a piezoelectric substrate electromechanical coupling coefficient, where C 1 is a numerical factor such that C 1 >2; coupling an acoustic wave filter to the piezoelectric substrate, the acoustic wave filter including at least a second acoustic wave transducer; and coupling the microelectronic inductance to the second acoustic wave transducer to provide a predetermined electrical impedance.
Claim 12
Dependent Claim 50 words
A method as claimed in claim 9, wherein coupling the microelectronic inductance to the second acoustic wave transducer includes coupling the microelectronic inductance in series with the second acoustic wave transducer to provide an electrical impedance match for the second acoustic wave transducer over at least a first frequency range.
Claim 13
Dependent Claim 50 words
A method as claimed in claim 9, wherein coupling the microelectronic inductance to the second acoustic wave transducer includes coupling the microelectronic inductance in shunt with the second acoustic wave transducer to provide an electrical impedance match for the second acoustic wave transducer over at least a first frequency range.
Claim 14
Dependent Claim 124 words
A microelectronic filter including in combination: an acoustic wave propagating substrate; an acoustic wave transducer coupled to said acoustic wave propagating substrate to provide a microelectronic inductance, said acoustic wave transducer having an effective length L eff such that: L.sub.eff ≧C.sub.2 v.sub.a /f.sub.o k.sup.2, where C 2 is a numerical factor such that C 2 ≧2, v a represents an acoustic velocity, f o represents an acoustic wave transducer center frequency and k 2 denotes an acoustic wave propagating substrate electromechanical coupling coefficient; and an acoustic filter disposed on acoustic wave propagating substrate, said acoustic filter including an input and an output, said input electrically coupled to said microelectronic inductance to provide an electrical impedance match over at least a first range of frequencies.
Claim 15
Dependent Claim 124 words
A microelectronic filter including in combination: an acoustic wave propagating substrate; an acoustic wave transducer coupled to said acoustic wave propagating substrate to provide a microelectronic inductance, said acoustic wave transducer having an effective length L eff such that: L.sub.eff ≧C.sub.2 v.sub.a /f.sub.o k.sup.2, where C 2 is a numerical factor such that C 2 ≧2, v a represents an acoustic velocity, f o represents an acoustic wave transducer center frequency and k 2 denotes an acoustic wave propagating substrate electromechanical coupling coefficient; and an acoustic filter disposed on acoustic wave propagating substrate, said acoustic filter including an input and an output, said input electrically coupled to said microelectronic inductance to provide an electrical impedance match over at least a first range of frequencies.
Claim 16
Dependent Claim 35 words
A microelectronic filter as claimed in claim 12, wherein said microelectronic inductance is coupled in series with said input to provide an electrical impedance match to a predetermined impedance over said first range of frequencies.
Claim 17
Dependent Claim 35 words
A microelectronic filter as claimed in claim 12, wherein said microelectronic inductance is coupled in shunt with said input to provide an electrical impedance match to a predetermined impedance over said first range of frequencies.
Claim 18
Dependent Claim 76 words
A component as claimed in claim 12, further comprising: a first acoustic wave reflector disposed to a first side of said acoustic wave transducer( in a propagation path of at least some of an acoustic wave emitted from said acoustic wave transducer; and a second acoustic wave reflector disposed to a second side of said acoustic wave transducer in another propagation path of at least some of said acoustic wave emitted from said acoustic wave transducer.
Claim 19
Dependent Claim 42 words
A component as claimed in claim 12, wherein said acoustic wave propagating substrate comprises a member of the group consisting of lithium niobate, lithium tantalate, bismuth germanium oxide, bismuth silicon oxide, quartz, gallium arsenide, silicon, cadmium sulfide, aluminum nitride and zinc oxide.
Claim 20
Dependent Claim 25 words
A component as claimed in claim 15, wherein said first and second acoustic wave reflectors comprise reflection elements spaced an integral number of wavelengths apart.
Claim 21
Independent Claim 137 words
An apparatus comprising a surface acoustic wave filter having a predetermined input impedance including in combination: an acoustic wave propagating substrate; a first acoustic wave transducer acoustically coupled to said acoustic wave propagating substrate to provide an acoustic inductance, said first acoustic wave transducer having an effective number of electrode pairs N eff such that: N.sub.eff >C.sub.1 /k.sup.2, where C 1 is a numerical factor such that C 1 >2 and k 2 denotes an acoustic wave propagating substrate electromechanical coupling coefficient; and an acoustic wave filter acoustically coupled to said acoustic wave propagating substrate and electrically coupled to said acoustic inductance to provide a predetermined input impedance, said acoustic wave filter comprising at least a second acoustic wave transducer acoustically coupled to said acoustic wave propagating substrate and electrically coupled to said first acoustic wave transducer.
Claim 22
Independent Claim 137 words
An apparatus comprising a surface acoustic wave filter having a predetermined input impedance including in combination: an acoustic wave propagating substrate; a first acoustic wave transducer acoustically coupled to said acoustic wave propagating substrate to provide an acoustic inductance, said first acoustic wave transducer having an effective number of electrode pairs N eff such that: N.sub.eff >C.sub.1 /k.sup.2, where C 1 is a numerical factor such that C 1 >2 and k 2 denotes an acoustic wave propagating substrate electromechanical coupling coefficient; and an acoustic wave filter acoustically coupled to said acoustic wave propagating substrate and electrically coupled to said acoustic inductance to provide a predetermined input impedance, said acoustic wave filter comprising at least a second acoustic wave transducer acoustically coupled to said acoustic wave propagating substrate and electrically coupled to said first acoustic wave transducer.
Claim 23
Dependent Claim 39 words
An apparatus as claimed in claim 18, wherein said first acoustic wave transducer is electrically couple din series with said second acoustic wave transducer to provide an electrical impedance match to a predetermined impedance over a range of frequencies.
Claim 24
Dependent Claim 39 words
An apparatus as claimed in claim 18, wherein said first acoustic wave transducer is electrically coupled in shunt with said second acoustic wave transducer to provide an electrical impedance match to a predetermined impedance over a range of frequencies.
Claim 25
Dependent Claim 42 words
An apparatus as claimed in claim 18, further comprising a first acoustic wave reflector disposed to a first side of said acoustic wave transducer in a propagation path of at least some of an acoustic wave emitted from said acoustic wave transducer.
Claim 26
Dependent Claim 42 words
An apparatus as claimed in claim 21, further comprising a second acoustic wave reflector disposed to a second side of said acoustic wave transducer in another propagation path of at least some of said acoustic wave emitted from said acoustic wave transducer.
Claim 27
Dependent Claim 157 words
In a radio frequency apparatus, at least one acoustic wave inductive device comprising: an acoustic wave propagating substrate for supporting propagation of acoustic waves; an input for supplying electrical input signals; a first acoustic wave transducer electrically coupled to said input and acoustically coupled to said acoustic wave propagating substrate to provide an acoustic wave inductive device, said first acoustic wave transducer having a length L in accordance with: L≧C.sub.2 v.sub.a /f.sub.o k.sup.2, where C 2 is a numerical factor such that C 2 ≧2, v a represents an acoustic velocity, f o represents a center frequency of said first acoustic wave transducer and k 2 denotes an acoustic wave propagating substrate electromechanical coupling coefficient; and an acoustic wave filter including second and third acoustic wave transducers acoustically coupled to each other, said first acoustic wave transducer electrically coupled to said second acoustic wave transducer to provide an electrical impedance match over a first range of frequencies.
Claim 28
Dependent Claim 157 words
In a radio frequency apparatus, at least one acoustic wave inductive device comprising: an acoustic wave propagating substrate for supporting propagation of acoustic waves; an input for supplying electrical input signals; a first acoustic wave transducer electrically coupled to said input and acoustically coupled to said acoustic wave propagating substrate to provide an acoustic wave inductive device, said first acoustic wave transducer having a length L in accordance with: L≧C.sub.2 v.sub.a /f.sub.o k.sup.2, where C 2 is a numerical factor such that C 2 ≧2, v a represents an acoustic velocity, f o represents a center frequency of said first acoustic wave transducer and k 2 denotes an acoustic wave propagating substrate electromechanical coupling coefficient; and an acoustic wave filter including second and third acoustic wave transducers acoustically coupled to each other, said first acoustic wave transducer electrically coupled to said second acoustic wave transducer to provide an electrical impedance match over a first range of frequencies.
Claim 29
Dependent Claim 39 words
An apparatus as claimed in claim 23, said at least one acoustic wave inductive device further comprising means for reflecting acoustic waves, said acoustic reflector means located in a propagation path of at least some of said acoustic signals.
Claim 30
Dependent Claim 89 words
An apparatus as claimed in claim 24, wherein said acoustic reflector means further comprises: a first acoustic reflector for reflecting acoustic waves, said first acoustic reflector located to a first side of said first acoustic wave transducer and in a principal propagation path of at least some of said acoustic signals; and a second acoustic reflector for reflecting acoustic waves, said second acoustic reflector located to a second side of said first acoustic wave transducer and in another principal propagation path of at least some of said acoustic signals.
Claim 31
Dependent Claim 25 words
An apparatus as claimed in claim 24, wherein said first and second acoustic wave reflectors comprise reflection elements spaced an integer number of wavelengths apart.
Claim 32
Dependent Claim 40 words
An apparatus as claimed in claim 23, wherein said first acoustic wave transducer is electrically coupled in shunt with said second acoustic wave transducer to provide an electrical impedance match to a predetermined impedance over said first range of frequencies.
Claim 33
Dependent Claim 40 words
An apparatus as claimed in claim 23, wherein said first acoustic wave transducer is electrically coupled in series with said second acoustic wave transducer to provide an electrical impedance match to a predetermined impedance over said first range of frequencies.
Claim 34
Dependent Claim 95 words
An apparatus as claimed in claim 24, said acoustic wave filter further comprising a fourth acoustic wave transducer coupled to said third acoustic wave transducer to provide an impedance match over a second range of frequencies, said fourth acoustic wave transducer having a length L in accordance with: L≧C.sub.2 v.sub.a4 /f.sub.o4 k.sub.4.sup.2, where C 2 is a numerical factor such that C 2 ≧2, v a4 represents an acoustic velocity, f o4 represents a center frequency of said fourth acoustic wave transducer and k 4 2 denotes an acoustic wave propagating substrate electromechanical coupling coefficient.
Claim 35
Dependent Claim 42 words
An apparatus as claimed in claim 23, wherein said acoustic wave propagating substrate comprises a member of the group consisting of lithium niobate, lithium tantalate, bismuth germanium oxide, bismuth silicon oxide, quartz, gallium arsenide, silicon, cadmium sulfide, aluminum nitride and zinc oxide.
Claim 36
Dependent Claim 40 words
An apparatus as claimed in claim 29, wherein said fourth acoustic wave transducer is electrically coupled in series with said third acoustic wave transducer to provide an electrical impedance match to a predetermined impedance over said second range of frequencies.
Claim 37
Dependent Claim 40 words
An apparatus as claimed in claim 29, wherein said fourth acoustic wave transducer is electrically coupled in shunt with said third acoustic wave transducer to provide an electrical impedance match to a predetermined impedance over said second range of frequencies.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-02-14 1997-08-16 1998-02-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-02-14 2001-08-16 2002-02-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-02-14 2005-08-16 2006-02-15 $7700.00 Window Closed / Lapsed

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