1. An apparatus comprising:
a plurality of varactor stages that are electrically coupled in parallel;
wherein for two or more varactor stages of the plurality of varactor stages, each respective varactor stage of the two or more varactor stages includes a set of one or more varactors that are electrically coupled to a tuning source;
wherein each respective varactor stage of the two or more varactor stages is configured to vary a respective capacitance in response to a tuning voltage from the tuning source;
wherein each respective varactor stage of the two or more varactor stages is configured to be concurrently biased at a different respective voltage level.
2. The apparatus of claim 1, wherein the plurality of varactor stages comprises:
a first varactor stage configured to be biased at a first voltage level;
a second varactor stage configured to be biased at a second voltage level that is different than the first voltage level; and
a third varactor stage configured to be biased at a third voltage level that is different than the first voltage level and the second voltage level.
3. The apparatus of claim 2, wherein the second voltage level is greater than the first voltage level by an offset amount and wherein the third voltage level is less than the first voltage level by the offset amount.
4. The apparatus of claim 1, wherein each varactor stage of the two or more varactor stages includes at least one switched varactor and at least one non-switched varactor.
5. The apparatus of claim 4, wherein the at least one switched varactor is configured to be connected to the tuning source in response to a set of one or more digital control signals.
6. The apparatus of claim 1, wherein each respective varactor stage of the two or more varactor stages includes a set of one or more capacitive structures that capacitively couple the respective varactor stage with a tank circuit.
7 The apparatus as recited in claim 1, wherein the apparatus is an integrated circuit package.
8. The apparatus as recited in claim 1, wherein the plurality of varactor stages are configured to operate in the 60 GHz frequency band.
9. An apparatus comprising:
a plurality of varactor stages;
wherein for two or more varactor stages of the plurality of varactor stages, each respective varactor stage of the two or more varactor stages includes a respective set of one or more switched varactors and a respective set of one or more non-switched varactors;
wherein for each respective varactor stage of the two or more varactor stages, the respective varactor stage is configured such that a digital control signal controls how many switched varactors in the respective set of one or more switched varactors are connected to a tuning source;
wherein for a first varactor stage of the two or more varactor stages, a first switched varactor included in the first varactor stage is configured to be connected to the tuning source based on a first bit of the digital control signal;
wherein for a second varactor stage of the two or more varactor stages, a second switched varactor included in the second varactor stage is configured to be connected to the tuning source based on the first bit of the digital control signal.
10. The apparatus of claim 9,
wherein for a first varactor stage of the two or more varactor stages, the respective set of one or more switched varactors and the respective set of one or more non-switched varactors are biased at a first voltage level;
wherein for a second varactor stage of the two or more varactors stages, the respective set of one or more switched varactors and the respective set of one or more non-switched varactors are biased at a second voltage level that is different than the first voltage level.
11. The apparatus of claim 9,
wherein for each respective varactor stage of the two or more varactor stages, the respective set of one or more switched varactors includes a plurality of switched varactors that are part of a plurality of varactor sub-stages;
wherein two or more varactor sub-stages of the plurality of varactor sub-stages are configured to be controlled by different bits of the digital control signal.
12. The apparatus of claim 11, wherein each varactor sub-stage of the two or more varactor sub-stages includes two varactors that are electrically coupled to a switch that is controlled by a respective bit of the digital control signal.
13. The apparatus of claim 9, further comprising:
a switched capacitor array that is configured such that the digital control signal controls how many capacitors are connected within a voltage controlled oscillator to change an operating frequency band of the voltage controlled oscillator.
14. The apparatus of claim 13, wherein each varactor stage of the two or more varactor stages is configured such that the digital control signal connects additional switched varactors to the tuning source as the operating frequency band of the voltage controlled oscillator is decreased and disconnects switched varactors from the tuning source as the operating frequency band of the voltage controlled oscillator is increased.
15. The apparatus of claim 9, wherein each respective varactor stage of the two or more varactor stages includes a set of one or more capacitive structures that capacitively couple the respective varactor stage with one or more other components within a voltage controlled oscillator.
16. The apparatus of claim 9, wherein the plurality of varactor stages are coupled in parallel; wherein for each respective varactor stage of the two or more varactor stages, a plurality of varactor sub-stages are electrically coupled in parallel; wherein each varactor sub-stage includes at least one of a switched varactor or a non-switched varactor.
17. The apparatus as recited in claim 9, wherein the apparatus is an integrated circuit package.
18. A circuit comprising:
a first varactor stage configured to be biased at a first voltage level;
wherein the first varactor stage includes a first varactor sub-stage, a second varactor sub-stage, and a third varactor sub-stage;
wherein the second varactor sub-stage includes a first switch that is configured to connect a first varactor and a second varactor to a tuning source in response to a first control signal;
wherein the third varactor sub-stage includes a second switch that is configured to connect a third varactor and a fourth varactor to the tuning source in response to a second control signal;
a second varactor stage configured to be biased at a second voltage level that is different than the first voltage level;
wherein the second varactor stage includes a fourth varactor sub-stage, a fifth varactor sub-stage, and a sixth varactor sub-stage;
wherein the fifth varactor sub-stage includes a third switch that is configured to connect a fifth varactor and a sixth varactor to the tuning source in response to the first control signal;
wherein the sixth varactor sub-stage includes a fourth switch that is configured to connect a seventh varactor and an eighth varactor to the tuning source in response to the second control signal.
19. The circuit of claim 18, further comprising:
a third varactor stage configured to be biased at a third voltage level that is different than the first voltage level and the second voltage level;
wherein the third varactor stage includes a seventh varactor sub-stage, an eighth varactor sub-stage, and a ninth varactor sub-stage;
wherein the eighth varactor sub-stage includes a fifth switch that is configured to connect a ninth varactor and a tenth varactor to the tuning source in response to the first control signal;
wherein the ninth varactor sub-stage includes a sixth switch that is configured to connect a eleventh varactor and a twelfth varactor to the tuning source in response to the second control signal.
20. The circuit of claim 18, wherein the first varactor sub-stage includes a first non-switched varactor and a second non-switched varactor that are connected to the tuning source, wherein the third varactor sub-stage includes a third non-switched varactor and a fourth non-switched varactor that are connected to the tuning source.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A ring laser gyroscope that includes a frame, a cavity in the frame, a first anode, a second anode and a cathode arranged to define a gain region in the cavity and to form a plasma extending between the first and second anodes in a gain medium within the gain region, a first mirror well formed in the frame between the first anode and the cathode, a first mirror mounted to the frame adjacent the first mirror well, a second mirror well formed in the frame between the second anode and the cathode, a second mirror mounted to the frame adjacent the second mirror well, the first and second mirror wells being arranged to intersect the cavity, comprising:
a first plasma shunt located in the first mirror well and arranged to prevent the plasma from contacting the first mirror; and
a second plasma shunt located in the second mirror well and arranged to prevent the plasma from contacting the second mirror.
2. The ring laser gyroscope of claim 1 wherein the first plasma shunt comprises a first electrical conductor located in the first mirror well and arranged such that contact between the plasma and the first electrical conductor quenches the plasma in the first mirror well and produces an electrical current in the first electrical conductor; and wherein the second plasma shunt comprises a second electrical conductor located in the second mirror well and arranged such that contact between the plasma and the second electrical conductor quenches the plasma in the second mirror well and produces an electrical current in the second electrical conductor.
3. The ring laser gyroscope of claim 2 wherein the first and second electrical conductors are formed as first and second metallized strips arranged to extend across the first and second mirror wells, respectively and are spaced apart from the first and second mirrors.
4. The ring laser gyroscope of claim 2 wherein the first and second electrical conductors are formed as first and second metal wires arranged to extend across the first and second mirror wells, respectively and are spaced apart from the first and second mirrors.
5. The ring laser gyroscope of claim 1 wherein the first plasma shunt comprises a first diversion passage formed in the frame and arranged to extend through the first mirror well and to intersect the cavity at two locations near the first mirror well that are spaced apart from the first mirror and arranged such that the plasma fills the first diversion passage in the first mirror well without contacting the first mirror; and wherein the second plasma shunt comprises a second diversion passage formed in the frame and arranged to extend through the second mirror well and to intersect the cavity at two locations near the second mirror well that are spaced apart from the second mirror and arranged such that the plasma fills the second diversion passage in the second mirror well without contacting the second mirror.
6. A method for preventing plasma damage to mirrors in a ring laser gyroscope gain medium, the ring laser gyroscope including a frame, a cavity in the frame, a first anode, a second anode and a cathode arranged to define a gain region in the cavity and to form a plasma extending between the first and second anodes the gain medium within the gain region, a first mirror well formed in the frame between the first anode and the cathode, a first mirror mounted to the frame adjacent the first mirror well, a second mirror well formed in the frame between the second anode and the cathode, a second mirror mounted to the frame adjacent the second mirror well, the first and second mirror wells being arranged to intersect the cavity, comprising the steps of:
(a) placing a first plasma shunt in the first mirror well spaced apart from the first mirror and arranged to prevent the plasma from contacting the first mirror; and
(b) placing a second plasma shunt in the second mirror well spaced apart from the second mirror and arranged to prevent the plasma from contacting the second mirror.
7. The method of claim 6 wherein step (a) comprises the steps of placing a first electrical conductor in the first mirror well and arranging the first electrical conductor such that contact between the plasma and the first electrical conductor quenches the plasma in the first mirror well and produces an electrical current in the first electrical conductor; and wherein step (b) comprises the steps of placing a second electrical conductor in the second mirror well and arranging the second electrical conductor such that contact between the plasma and the second electrical conductor quenches the plasma in the second mirror well and produces an electrical current in the second electrical conductor.
8. The method of claim 7 including the steps of forming the first and second electrical conductors as first and second metallized strips and arranging the first and second metallized strips to extend across the first and second mirror wells, respectively spaced apart from the first and second mirrors.
9. The method of claim 7 including the steps of forming the first and second electrical conductors as first and second metal wires arranging the first and second metal wires to extend across the first and second mirror wells spaced apart from the first and second mirrors.
10. The method of claim 6 wherein step (a) comprises the steps of forming a first diversion passage in the frame to extend through the first mirror well to intersect the cavity at two locations near the first mirror well that are spaced apart from the first mirror and arranging the first diversion passage such that the plasma fills the first diversion passage in the first mirror well without contacting the first mirror; and wherein step (b) comprises the steps of forming a second diversion passage in the frame to extend through the second mirror well and arranging the second diversion passage to intersect the cavity at two locations near the second mirror well that are spaced apart from the second mirror and arranged such that the plasma fills the second diversion passage in the second mirror well without contacting the second mirror.