Inductor capacitor tank for resonator

Patent metadata

Field	Value
Publication number	US-2016336914-A1
Application number	US-201615050436-A
Country	US
Kind code	A1
Filing date	Feb 22, 2016
Priority date	May 14, 2015
Publication date	Nov 17, 2016
Grant date	—

Abstract

An inductor capacitor (LC) tank includes a first inductor and a first tunable capacitive array. The first inductor has a first terminal and a second terminal, and the first tunable capacitive array has a first terminal and a second terminal. The first tunable capacitive array is at a path branching from a first point between the first terminal and the second terminal of the first inductor, the first terminal of the first tunable capacitive array is coupled to the first point, and the second terminal of the first tunable capacitive array and the second terminal of the first inductor are coupled to a reference voltage.

First claim

What is claimed is:

1 . An inductor capacitor (LC) tank, comprising:
a first inductor, having a first terminal and a second terminal; and a first tunable capacitive array, having a first terminal and a second terminal; wherein the first tunable capacitive array, comprising a plurality of tunable capacitive units which are independently controllable, is at a path branching from a first point between the first terminal and the second terminal of the first inductor, the first terminal of the first tunable capacitive array is coupled to the first point, and the second terminal of the first tunable capacitive array and the second terminal of the first inductor are coupled to a reference voltage.

2 . The LC tank of claim 1 , wherein a portion of the first inductor from the second terminal of the first inductor to the first point forms a first sub-inductor, another portion of the first inductor from the first point to the first terminal of the first inductor forms a second sub-inductor, and an inductance of the first sub-inductor is less than an inductance of the second sub-inductor.

3 . The LC tank of claim 1 , wherein the first inductor is a spiral coil, and a distance from the second terminal of the first inductor to the first point is less than a distance from the first point to the first terminal of the first inductor, wherein the distances are measured along sub-coils of the spiral coil.

4 . The LC tank of claim 1 , wherein the first tunable capacitive array is controlled by digital signals.

5 . The LC tank of claim 1 , wherein the first tunable capacitive array is arranged to tune an oscillation frequency of the LC tank.

6 . The LC tank of claim 1 , further comprising:
a first capacitive element at another path branching from the first terminal of the first inductor, wherein the first capacitive element has a first terminal coupled to the first terminal of the first inductor and a second terminal coupled to the reference voltage or another reference voltage.

7 . The LC tank of claim 6 , wherein a portion of the first inductor from the second terminal of the first inductor to the first point forms a first sub-inductor, another portion of the first inductor from the first point to the first terminal of the first inductor forms a second sub-inductor, and an inductance of the first sub-inductor is less than an inductance of the second sub-inductor.

8 . The LC tank of claim 6 , wherein the first inductor is a spiral coil, and a distance from the second terminal of the first inductor to the first point is less than a distance from the first point to the first terminal of the first inductor, wherein the distances are measured along sub-coils of the spiral coil.

9 . The LC tank of claim 1 , further comprising:
a second tunable capacitive array at another path branching from a second point between the first terminal of the first inductor and the first point, wherein the second tunable capacitive array has a first terminal and a second terminal, the first terminal of the second tunable capacitive array is coupled to the second point, and the second terminal of the second tunable capacitive array is coupled to the reference voltage or another reference voltage.

10 . The LC tank of claim 9 , wherein the second tunable capacitive array is arranged to perform a calibration process, using a frequency tuning relationship between the first tunable capacitive array and the second tunable capacitive array.

11 . The LC tank of claim 9 , wherein the second tunable capacitive array is arranged to tune an oscillation frequency of the LC tank.

12 . The LC tank of claim 9 , wherein a ratio of a differentiation of an oscillation frequency with respect to a capacitance of the second tunable capacitive array to a differentiation of an oscillation frequency with respect to a capacitance of the first tunable capacitive array is a power of 2.

13 . The LC tank of claim 1 , further comprising:
a second inductor having a first terminal and a second terminal, wherein the second terminal of the second inductor is coupled to the second terminal of the first inductor.

14 . The LC tank of claim 13 , further comprising:
a second tunable capacitive array at another path branching from a second point between the first terminal and the second terminal of the second inductor, wherein the second tunable capacitive array has a first terminal and a second terminal, the first terminal of the second tunable capacitive array is coupled to the second point, and the second terminal of the second tunable capacitive array is coupled to the reference voltage or another reference voltage.

15 . The LC tank of claim 14 , wherein the second tunable capacitive array is arranged to tune an oscillation frequency of the LC tank.

16 . The LC tank of claim 14 , wherein a portion of the second inductor from the second terminal of the second inductor to the second point forms a first sub-inductor, another portion of the second inductor from the second point to the first terminal of the second inductor forms a second sub-inductor, and an inductance of the first sub-inductor is less than an inductance of the second sub-inductor.

17 . The LC tank of claim 14 , wherein the second inductor is a spiral coil, and a distance from the second terminal of the second inductor to the second point is less than a distance from the second point to the first terminal of the second inductor, wherein the distances are measured along sub-coils of the spiral coil.

18 . The LC tank of claim 14 , further comprising:
a first capacitive element, having three terminals, wherein a first terminal of the three terminals is coupled to the first terminal of the first inductor, a second terminal of the three terminals is coupled to the first terminal of the second inductor, and a third terminal of the three terminals is coupled to yet another reference voltage or left floating.

19 . The LC tank of claim 18 , wherein a portion of the second inductor from the second terminal of the second inductor to the second point forms a first sub-inductor, another portion of the second inductor from the second point to the first terminal of the second inductor forms a second sub-inductor, and an inductance of the first sub-inductor is less than an inductance of the second sub-inductor.

20 . The LC tank of claim 18 , wherein the second inductor is a spiral coil, and a distance from the second terminal of the second inductor to the second point is less than a distance from the second point to the first terminal of the second inductor, wherein the distances are measured along sub-coils of the spiral coil.

21 . The LC tank of claim 14 , further comprising:
a third tunable capacitive array at another path branching from a third point between the first terminal of the second inductor and the second point, wherein the third tunable capacitive array has a first terminal and a second terminal, the first terminal of the third tunable capacitive array is coupled to the third point, and the second terminal of the third tunable capacitive array is coupled to the reference voltage.

22 . The LC tank of claim 21 , wherein the third tunable capacitive array is arranged to perform a calibration process.

23 . The LC tank of claim 21 , wherein the third tunable capacitive array is arranged to tune an oscillation frequency of the LC tank.

24 . The LC tank of claim 21 , wherein a ratio of a differentiation of an oscillati

Assignees

• Mediatek Inc

Inventors

• Wang Kun-Yin
• Chiu Wei-Hao
• Lin Ang-Sheng

Classifications

• H03H7/0115 Primary

  comprising only inductors and capacitors (H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence) · CPC title

• H01F17/0006

  Printed inductances (printed coils for dynamo-electric machines H02K3/26; printed circuits H05K) · CPC title

• H03H5/12 Primary

  with at least one voltage- or current-dependent element · CPC title

• H01F2017/0073

  with a special conductive pattern, e.g. flat spiral · CPC title

• H03B5/18 Primary

  with frequency-determining element comprising distributed inductance and capacitance · CPC title