TUNABLE CAPACITOR

• US 20130257558A1
• Filed: 03/29/2013
• Published: 10/03/2013
• Est. Priority Date: 04/03/2012
• Status: Active Grant

• Current Assignee: HiDeep Inc.
• Original Assignee: HiDeep Inc.
• Inventors: KIM, Bonkee, CHO, Youngho, IM, Donggu, KIM, Bumkyum
• Granted Patent: US 9,712,132 B2
• Time in Patent Office: Days
• US Class Current: 333/32
• CPC Class Codes: H01L 2223/6655 Matching arrangements, e.g. arrangement of inductive and capacitive components
• CPC Class Codes: H01L 23/642 Capacitive arrangements H01L23/49589, H01L23/645, H01L23/647, H01L23/66 take precedence; capacitive effects between wiring layers on the semiconductor body H01L23/5222
• CPC Class Codes: H01L 23/66 High-frequency adaptations
• CPC Class Codes: H01L 27/0251 for MOS devices
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H03H 11/28 Impedance matching networks
• CPC Class Codes: H03H 7/38 Impedance-matching networks

Abstract

Disclosed is a tunable capacitor. The tunable capacitor according to a first embodiment of the present invention includes: a variable capacitor unit placed between a first terminal and a second terminal; and a bypass switch which on/off controls a bypass connection between the first terminal and the second terminal, wherein the variable capacitor unit and the bypass switch are integrated on one semiconductor die or on one module. The tunable capacitor according to a second embodiment of the present invention includes: a variable capacitor unit placed between a first terminal and a second terminal; an impedance tuner placed between aground terminal and either the first terminal or the second terminal; and a tuning switch which on/off controls the connection between the variable capacitor unit and an impedance tuner, wherein the variable capacitor unit, the impedance tuner and the tuning switch are integrated on one semiconductor die or on one module.

Claims

1. A tunable capacitor comprising:

a variable capacitor unit placed between a first terminal and a second terminal; and

a bypass switch which on/off controls a bypass connection between the first terminal and the second terminal,

wherein the variable capacitor unit and the bypass switch are integrated on one semiconductor die or on one module.

3. The tunable capacitor of claim 1, comprising a tuning switch which on/off controls a connection between the variable capacitor unit and an impedance tuner connected in parallel to at least one of both terminals of the variable capacitor unit, wherein the variable capacitor unit, the bypass switch and the tuning switch are integrated on one semiconductor die or on one module.

4. The tunable capacitor of any one of claim 1, wherein the variable capacitor unit comprises at least one of a variable capacitor of which the capacitance is controlled by current or voltage and a MEMS variable capacitor.

6. The tunable capacitor of any one of claim 1, wherein the variable capacitor unit comprises:

a first capacitor; and

a switching transistor which switches on/off the connection of the first capacitor between the first terminal and the second terminal.

8. The tunable capacitor of claim 6, wherein when the switching transistor is in an on-state, a high signal H is applied to a gate terminal G, and a low signal L is applied to a body terminal B, a drain terminal D and a source terminal S, and wherein when the switching transistor is in an off-state, the low signal L is applied to the gate terminal G and the body terminal B, and the high signal H is applied to the drain terminal D and the source terminal S.

10. The tunable capacitor of claim 6, wherein the switching transistor is a stacked transistor formed by connecting in series a plurality of transistors.

12. The tunable capacitor of claim 6, wherein a gate terminal G and a body terminal B of the switching transistor are connected in series to a resistance respectively.

14. The tunable capacitor of claim 6, wherein the first capacitor is formed by connecting in series or in parallel a plurality of capacitors.

16. The tunable capacitor of claim 6, wherein an on/off operation of the switching transistor is performed by a high signal H and a low signal L.

18. The tunable capacitor of any one of claim 1, comprising a plurality of the variable capacitor units, wherein the plurality of the variable capacitor units are connected in parallel to each other, wherein each of the plurality of the variable capacitor units comprises a first capacitor and a switching transistor which switches on/off the connection of the first capacitor between the first terminal and the second terminal.

20. The tunable capacitor of claim 18, wherein an equivalent capacitance of the plurality of the variable capacitor units is 2^m-1×

C1 (here, m is a natural number less than n), wherein width-to-length ratios W/L of the switching transistors of the plurality of the variable capacitor units are 2^m-1×

W1 (here, m is a natural number less than n) respectively, and wherein the n is a number of the variable capacitor units, wherein the C1 is an equivalent capacitance of a particular variable capacitor unit, and wherein the W1 is a channel width-to-length ratio W/L of the switching transistor.

22. The tunable capacitor of claim 18, further comprising a fixed capacitor which is connected in parallel to a plurality of the tunable capacitors.

24. The tunable capacitor of claim 18, further comprising a controller which receives a digital control signal and controls on/off of the switching transistor.

26. The tunable capacitor of claim 18, wherein an on/off operation of the switching transistor is performed by a high signal H and a low signal L.

2. A tunable capacitor comprising:

a variable capacitor unit placed between a first terminal and a second terminal; and

a tuning switch which on/off controls a connection between the variable capacitor unit and an impedance tuner connected in parallel to at least one of both terminals of the variable capacitor unit,

wherein the variable capacitor unit and the tuning switch are integrated on one semiconductor die or on one module.

5. The tunable capacitor of any one of claim 2, wherein the variable capacitor unit comprises at least one of a variable capacitor of which the capacitance is controlled by current or voltage and a MEMS variable capacitor.

7. The tunable capacitor of any one of claim 2, wherein the variable capacitor unit comprises:

a first capacitor; and

a switching transistor which switches on/off the connection of the first capacitor between the first terminal and the second terminal.

9. The tunable capacitor of claim 7, wherein when the switching transistor is in an on-state, a high signal H is applied to a gate terminal G, and a low signal L is applied to a body terminal B, a drain terminal D and a source terminal S, and wherein when the switching transistor is in an off-state, the low signal L is applied to the gate terminal G and the body terminal B, and the high signal H is applied to the drain terminal D and the source terminal S.

11. The tunable capacitor of claim 7, wherein the switching transistor is a stacked transistor formed by connecting in series a plurality of transistors.

13. The tunable capacitor of claim 7, wherein a gate terminal G and a body terminal B of the switching transistor are connected in series to a resistance respectively.

15. The tunable capacitor of claim 7, wherein the first capacitor is formed by connecting in series or in parallel a plurality of capacitors.

17. The tunable capacitor of claim 7, wherein an on/off operation of the switching transistor is performed by a high signal H and a low signal L.

19. The tunable capacitor of any one of claim 2, comprising a plurality of the variable capacitor units, wherein the plurality of the variable capacitor units are connected in parallel to each other, wherein each of the plurality of the variable capacitor units comprises a first capacitor and a switching transistor which switches on/off the connection of the first capacitor between the first terminal and the second terminal.

21. The tunable capacitor of claim 19, wherein an equivalent capacitance of the plurality of the variable capacitor units is 2^m-1×

C1 (here, m is a natural number less than n), wherein width-to-length ratios W/L of the switching transistors of the plurality of the variable capacitor units are 2^m-1×

W1 (here, m is a natural number less than n) respectively, and wherein the n is a number of the variable capacitor units, wherein the C1 is an equivalent capacitance of a particular variable capacitor unit, and wherein the W1 is a channel width-to-length ratio W/L of the switching transistor.

23. The tunable capacitor of claim 19, further comprising a fixed capacitor which is connected in parallel to a plurality of the tunable capacitors.

25. The tunable capacitor of claim 19, further comprising a controller which receives a digital control signal and controls on/off of the switching transistor.

27. The tunable capacitor of claim 19, wherein an on/off operation of the switching transistor is performed by a high signal H and a low signal L.