Acoustically coupled resonator notch and bandpass filters

Patent metadata

Field	Value
Publication number	US-11005449-B2
Application number	US-201816210703-A
Country	US
Kind code	B2
Filing date	Dec 5, 2018
Priority date	Dec 7, 2017
Publication date	May 11, 2021
Grant date	May 11, 2021

Abstract

A notch filter includes an inductor coupled between an input node and an output node, and a dual-resonator structure coupled between the input node, the output node, and ground.

First claim

What is claimed is:

1. A notch filter comprising:
a first dual-resonator structure having a top electrode coupled to an input node, an intermediate electrode, and a bottom electrode;
a second dual-resonator structure having a top electrode coupled to an output node, an intermediate electrode, and a bottom electrode;
a first inductor having a first end directly coupled to the input node and a second end coupled to the output node; and
a second inductor coupled between the intermediate electrode of the first dual-resonator structure and the intermediate electrode of the second dual-resonator structure.

2. The notch filter of claim 1 , wherein an additional intermediate electrode of the first dual-resonator structure and an additional intermediate electrode of the second dual-resonator structure are coupled to ground.

3. The notch filter of claim 1 , wherein the bottom electrode of the first dual-resonator structure and the bottom electrode of the second dual-resonator structure are coupled together.

4. The notch filter of claim 1 , wherein the first and second dual- resonator structures each comprise a coupled resonator filter.

5. The notch filter of claim 1 , wherein the first and second dual-resonator structures each comprise a film bulk acoustic resonator.

6. A notch filter comprising:
a first dual-resonator structure having a top electrode coupled to an input node, an intermediate electrode, and a bottom electrode;
a second dual-resonator structure having a top electrode coupled to an output node, an intermediate electrode, and a bottom electrode;
a first inductor having a first end coupled to the input node and a second end directly coupled to the output node; and
a second inductor coupled between the intermediate electrode of the first dual-resonator structure and the intermediate electrode of the second dual-resonator structure.

7. The notch filter of claim 6 , wherein an additional intermediate electrode of the first dual-resonator structure and an additional intermediate electrode of the second dual-resonator structure are coupled to ground.

8. The notch filter of claim 6 , wherein the bottom electrode of the first dual-resonator structure and the bottom electrode of the second dual-resonator structure are coupled together.

9. The notch filter of claim 6 , wherein the first and second dual-resonator structures each comprise a coupled resonator filter.

10. The notch filter of claim 6 , wherein the first and second dual-resonator structures each comprise a film bulk acoustic resonator.

11. A notch filter comprising:
a first dual-resonator structure having a top electrode coupled to an input node, an intermediate electrode, and a bottom electrode;
a second dual-resonator structure having a top electrode coupled to an output node, an intermediate electrode, and a bottom electrode;
a first inductor having a first end coupled to the input node and a second end coupled to the output node; and
a second inductor having a first end coupled between the intermediate electrode of the first dual-resonator structure and the intermediate electrode of the second dual-resonator structure and a second end coupled to ground, wherein the second inductor comprises an inductor component external to the first dual-resonator structure and to the second dual-resonator structure.

12. The notch filter of claim 11 , wherein an additional intermediate electrode of the first dual-resonator structure and an additional intermediate electrode of the second dual-resonator structure are coupled to ground.

13. The notch filter of claim 11 , wherein the bottom electrode of the first dual-resonator structure and the bottom electrode of the second dual-resonator structure are coupled together.

14. The notch filter of claim 11 , wherein the first and second dual-resonator structures each comprise a coupled resonator filter.

15. The notch filter of claim 11 , wherein the first and second dual-resonator structures each comprise a film bulk acoustic resonator.

16. A method comprising:
filtering a signal using a notch filter comprising a first dual-resonator structure having a top electrode coupled to an input node for receiving the signal, an intermediate electrode, and a bottom electrode; a second dual-resonator structure having a top electrode coupled to an output node for providing a filtered signal, an intermediate electrode, and a bottom electrode; a first inductor having a first end directly coupled to the input node and a second end directly coupled to the output node; and a second inductor coupled between the intermediate electrode of the first dual-resonator structure and the intermediate electrode of the second dual-resonator structure.

17. The method of claim 16 , wherein an additional intermediate electrode of the first dual-resonator structure and an additional intermediate electrode of the second dual-resonator structure are coupled to ground.

18. The method of claim 16 , wherein the bottom electrode of the first dual-resonator structure and the bottom electrode of the second dual-resonator structure are coupled together.

19. The notch filter of claim 16 , wherein the first and second dual-resonator structures each comprise a coupled resonator filter.

20. The notch filter of claim 16 , wherein the first and second dual-resonator structures each comprise a film bulk acoustic resonator.

Assignees

• Infineon Technologies Ag

Inventors

• Bauder Ruediger
• Bogner Andreas
• Timme Hans-Joerg

Classifications

• H03H9/205

  having multiple resonators (crystal tuning forks H03H9/21) · CPC title

• H03H9/131

  consisting of a multilayered structure · CPC title

• H03H7/12

  Bandpass or bandstop filters with adjustable bandwidth and fixed centre frequency (H03H7/09 takes precedence) · CPC title

• H03H7/0161

  Bandpass filters (H03H7/12 takes precedence) · CPC title

• H03H7/0115 Primary

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