Resonator having distributed transconductance elements

Patent metadata

Field	Value
Publication number	US-9948236-B2
Application number	US-201614993217-A
Country	US
Kind code	B2
Filing date	Jan 12, 2016
Priority date	Feb 25, 2014
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

A method includes forming a resonator comprising a plurality of switched impedances spatially distributed within the resonator, selecting a resonant frequency for the resonator, and distributing two or more transconductance elements within the resonator based on the selected resonant frequency. Distributing the two or more transconductance elements may include non-uniformly distributing the two or more transconductance elements within the resonator.

First claim

What is claimed is:

1. An apparatus comprising:
a resonator comprising:
a plurality of switched impedances spatially distributed within the resonator; and
a corresponding plurality of transconductance elements distributed within respective distances among the switched impedances;

wherein the resonator has a given desired resonant frequency and a given amplitude of response;
wherein combined pairs of the switched impedances and transconductance elements have respective parasitic resonant frequencies which are higher than the given desired resonant frequency and have respective amplitudes of response which are lower than the given amplitude of response; and
wherein a given distance between a given one of the switched impedances and a given one of the transconductance elements is controlled based on a relationship between an impedance value of the given switched impedance and a transconductance value of the given transconductance element.

2. The apparatus of claim 1 wherein the apparatus is a voltage controlled oscillator.

3. The apparatus of claim 2 wherein the voltage controlled oscillator comprises at least one of a wide-tuning range oscillator, a digitally controlled oscillator and a millimeter wave oscillator.

4. The apparatus of claim 1 wherein the apparatus is an active filter.

5. The apparatus of claim 4 wherein the active filter comprises at least one of a switched impedance filter, a switched capacitor transconductance filter and a programmable narrowband band select filter.

6. The apparatus of claim 1 wherein the switched impedances comprise a capacitor array.

7. The apparatus of claim 6 wherein:
one or more interconnects between capacitors in the capacitor array contribute respective parasitic inductances in the resonator; and
the transconductance elements are distributed within the capacitor array to reduce the parasitic inductances of the one or more interconnects.

8. The apparatus of claim 1 wherein:
the transconductance elements have associated therewith different transconductance values;
the switched impedances comprise capacitors having associated therewith different capacitance values; and
wherein the transconductance elements are distributed within the resonator such that the transconductance values are proportional to the capacitance values.

9. The apparatus of claim 8 wherein the given distance between the given switched impedance and the given transconductance element is controlled based on a relationship between the capacitance value of the given switched impedance and the transconductance value of the given transconductance element.

10. The apparatus of claim 1 wherein:
the transconductance elements have associated therewith different transconductance values;
the switched impedances comprise inductors having associated therewith different inductance values; and
wherein the transconductance elements are distributed within the resonator such that the transconductance values are proportional to the inductance values.

11. The apparatus of claim 10 wherein the given distance between the given switched impedance and the given transconductance element is controlled based on a relationship between the inductance value of the given switched impedance and the transconductance value of the given transconductance element.

12. The apparatus of claim 1 wherein the transconductance elements are distributed based on a target narrowband bandpass transfer function.

13. The apparatus of claim 1 wherein an operating frequency of the resonator is 20 gigahertz or greater.

14. The apparatus of claim 1 wherein physical dimensions of the apparatus are greater than 1/100 of a wavelength of the apparatus.

15. The apparatus of claim 1 wherein physical dimensions of the apparatus are greater than 1/1000 of a wavelength of the apparatus.

16. An integrated circuit comprising:
a resonator comprising:
a plurality of switched impedances spatially distributed within the resonator; and
a corresponding plurality of transconductance elements distributed within respective distances among the switched impedances;

wherein the resonator has a given desired resonant frequency and a given amplitude of response;
wherein combined pairs of the switched impedances and transconductance elements have respective parasitic resonant frequencies which are higher than the given desired resonant frequency and have respective amplitudes of response which are lower than the given amplitude of response; and
wherein a given distance between a given one of the switched impedances and a given one of the transconductance elements is controlled based on a relationship between an impedance value of the given switched impedance and a transconductance value of the given transconductance element.

17. A voltage controlled oscillator comprising the integrated circuit of claim 16 .

18. An active filter comprising the integrated circuit of claim 16 .

19. A method comprising:
forming a resonator comprising a plurality of switched impedances spatially distributed within the resonator; and
forming a plurality of transconductance elements within respective distances among the switched impedances;
wherein the resonator has a given desired resonant frequency and a given amplitude of response;
wherein combined pairs of the switched impedances and transconductance elements have respective parasitic resonant frequencies which are higher than the given desired resonant frequency and have respective amplitudes of response which are lower than the given amplitude of response; and
wherein a given distance between a given one of the switched impedances and a given one of the transconductance elements is controlled based on a relationship between an impedance value of the given switched impedance and a transconductance value of the given transconductance element.

20. The method of claim 19 further comprising forming at least one of a voltage controlled oscillator and a resonator comprising the resonator.

Assignees

• IBM

Inventors

• Ferriss Mark A
• Friedman Daniel J
• Rylyakov Alexander V
• Sadhu Bodhisatwa
• Valdes Garcia Alberto

Classifications

• H03H11/0472

  Current or voltage controlled filters · CPC title

• H03H19/00

  Networks using time-varying elements, e.g. N-path filters · CPC title

• H03B5/00

  Generation of oscillations using amplifier with regenerative feedback from output to input (H03B9/00, H03B15/00 take precedence) · CPC title

• H03H11/0422

  using transconductance amplifiers, e.g. gmC filters · CPC title

• H03H19/004

  Switched capacitor networks · CPC title