Integrated tunable inductance network and method
First Claim
1. An integrated, tunable inductance network, comprising:
- a substrate,a plurality of inductors fabricated on said substrate, anda switching network-which is operable to interconnect selectable ones of said inductors to form an inductance network having an inductance value that depends upon the selected inductors, said inductance network having an input and output, said switching network comprising a plurality of micro-electromechanical (MEM) switches and integrated with said inductors on said substrate, each of said MEM switches switching in response to a respective control signal to set a total inductance across said input and output to one of a plurality of levels.
9 Assignments
0 Petitions
Accused Products
Abstract
An integrated, tunable inductance network features a number of fixed inductors fabricated on a common substrate along with a switching network made up of a number of micro-electromechanical (MEM) switches. The switches selectably interconnect the inductors to form an inductance network having a particular inductance value, which can be set with a high degree of precision when the inductors are configured appropriately. The preferred MEM switches introduce a very small amount of resistance, and the inductance network can thus have a high Q. The MEM switches and inductors can be integrated using common processing steps, reducing parasitic capacitance problems associated with wire bonds and prior art switches, increasing reliability, and reducing the space, weight and power requirements of prior art designs. The precisely tunable high-Q inductance network has wide applicability, such as in a resonant circuit which provides a narrow bandwidth frequency response which peaks at a specific predetermined frequency, making possible a highly selective performance low noise amplifier (LNA), or in an oscillator circuit so that a precise frequency of oscillation can be generated and changed as needed.
175 Citations
25 Claims
-
1. An integrated, tunable inductance network, comprising:
-
a substrate, a plurality of inductors fabricated on said substrate, and a switching network-which is operable to interconnect selectable ones of said inductors to form an inductance network having an inductance value that depends upon the selected inductors, said inductance network having an input and output, said switching network comprising a plurality of micro-electromechanical (MEM) switches and integrated with said inductors on said substrate, each of said MEM switches switching in response to a respective control signal to set a total inductance across said input and output to one of a plurality of levels. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. An integrated, tunable inductance network, comprising:
-
a plurality of inductors, a switching network which is operable to interconnect selectable ones of said inductors to form an inductance network having an inductance value that depends upon the selected inductors, said inductance network having an input and output, said switching network integrated with said inductors on a common substrate, a control device connected to said switching network and arranged to operate said switching network to cause said inductance network to present a desired inductance value between said input and output, and a memory device which is connected to said control device and arranged to cause said control device to configure said switching network to produce a desired inductance value between said input and output.
-
-
13. An integrated, tunable inductance network, comprising:
-
a plurality of inductors, and a switching network which is operable to interconnect selectable ones of said inductors to form an inductance network having an inductance value that depends upon the selected inductors, said inductance network having an input and output, said switching network including a respective pair of switches for each of said inductors, each inductor connected in series between its respective switch pair, said pairs of switches operable to completely isolate their respective inductors from said inductance network, each of said pairs of switches implemented with a single double-throw micro-electromechanical switch, said switching network integrated with said inductors on a common substrate.
-
-
14. A low noise amplifier (LNA) front end, comprising:
-
an active device, and an integrated tunable inductance network which forms a resonant circuit which is connected to said active device, said inductance network comprising a plurality of fixed inductors and a switching network, said switching network operable to interconnect selectable ones of said fixed inductors to form an inductance network having an inductance value that depends upon the selected fixed inductors, said switching network, said active device, and said fixed inductors integrated together on a common substrate, said switching network comprising a plurality of micro-electromechanical (MEM) switches, each of said MEM switches switching in response to a respective control signal, said active device and inductance network forming an LNA front end having a frequency response which peaks at a frequency which depends on the inductance value of said inductance network. - View Dependent Claims (15, 16, 17)
-
-
18. A low noise amplifier (LNA) front end, comprising:
-
an active device, an integrated tunable inductance network which forms a resonant circuit which is connected to said active device, said inductance network comprising a plurality of fixed inductors and a switching network, said switching network operable to interconnect selectable ones of said fixed inductors to form an inductance network having an inductance value that depends upon the selected fixed inductors, said switching network integrated with said fixed inductors on a common substrate, said active device and inductance network forming an LNA front end having a frequency response which peaks at a frequency which depends on the inductance value of said inductance network, a control device connected to said switching network and arranged to operate said switching network to cause said resonant circuit to resonate at a desired frequency, and a memory device which is connected to said control device and arranged to cause said control device to configure said switching network to produce a desired inductance value.
-
-
19. A tunable oscillator, comprising:
-
an amplifier, and an integrated tunable inductance network which forms a resonant circuit connected to said amplifier, said inductance network comprising a plurality of fixed inductors and a switching network, said switching network operable to interconnect selectable ones of said fixed inductors to form an inductance network having an inductance value that depends upon the selected fixed inductors, said switching network comprising a plurality of micro-electromechanical (MEM) switches, each of said MEM switches switching in response to a respective control signal, said switching network integrated with said fixed inductors on a common substrate to form a tunable oscillator that produces an output signal having a frequency which varies with the inductance value of said inductance network.
-
-
20. A method of providing a precise inductance value, comprising the steps of:
-
determining a desired inductance value, and electrically operating an integrated switching network to interconnect a plurality of integrated inductors into an inductance network having an inductance about equal to said desired inductance value, said switching network and said inductors integrated together on a common substrate, said switching network comprising a plurality of micro-electromechanical (MEM) switches, each of said MEM switches switching in response to a respective control signal to set the inductance of said network to one of a plurality of levels. - View Dependent Claims (21, 22, 23)
-
-
24. An inductor integrated with a micro-electromechanical (MEM) switch, comprising:
-
a substrate, a first layer which comprises a bottom electrode for a MEM switch, at least one gapped signal line, and a center tap for an inductor, said first layer located on the surface of said substrate, a second layer which comprises a contact electrode for said MEM switch and the coils for said inductor, said second layer located above said first layer, a third layer which comprises a cantilever arm for said MEM switch, said third layer located above said second layer, and a fourth layer which comprises a top electrode for said MEM switch, said fourth layer located above said third layer. - View Dependent Claims (25)
-
Specification