Time delay filters

• US 10,050,597 B2
• Filed: 07/18/2017
• Issued: 08/14/2018
• Est. Priority Date: 12/16/2015
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Kumu Networks, Inc.
• Inventors: Hahn, Wilhelm Steffen, Riddle, Alfred, Landi, Ernie
• Primary Examiner(s): Takaoka, Dean
• Application Number:
  US15/652,643
• Publication Number:
  US 20170317657A1
• Time in Patent Office: 392 Days
• Field of Search: 333166, 333202
• CPC Class Codes: H01L 2224/48195 the item being a discrete passive component
• CPC Class Codes: H03H 2001/0085 Multilayer, e.g. LTCC, HTCC, green sheets inside PCB filters H05K
• CPC Class Codes: H03H 7/0115 comprising only inductors and capacitors H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence
• CPC Class Codes: H03H 7/09 Filters comprising mutual inductance
• CPC Class Codes: H03H 7/1708 Comprising bridging elements, i.e. elements in a series path without own reference to ground and spanning branching nodes of another series path H03H7/07 takes precedence
• CPC Class Codes: H03H 7/1775 Parallel LC in shunt or branch path H03H7/1791 takes precedence
• CPC Class Codes: H03H 7/32 with lumped inductance and capacitance
• CPC Class Codes: H03H 7/325 Adjustable networks
• CPC Class Codes: H03H 7/34 with lumped and distributed reactance
• CPC Class Codes: H03H 7/345 Adjustable networks

Abstract

A time delay filter comprising a substrate; four coupled LC resonators, each having a coupling point; a first capacitor that electrically couples the first coupling point to the second coupling point; a second capacitor that electrically couples the second coupling point to the third coupling point; and a third capacitor that electrically couples the third coupling point to the fourth coupling point; the filter group delaying a signal output at the fourth coupling point relative to a signal input at the first coupling point.

Claims

1. A time delay filter comprising:

a substrate comprising a conductive ground region;

a first LC resonator coupled to the substrate and comprising;

a first coupling point,

a first capacitive element electrically coupled between the first coupling point and the ground region, and

a first inductive element electrically coupled between the first coupling point and the ground region;

a second LC resonator coupled to the substrate and comprising;

a second coupling point,

a second capacitive element electrically coupled between the second coupling point and the ground region, and

a second inductive element electrically coupled between the second coupling point and the ground region;

a third LC resonator coupled to the substrate and comprising;

a third coupling point,

a third capacitive element electrically coupled between the third coupling point and the ground region, and

a third inductive element electrically coupled between the third coupling point and the ground region;

a fourth LC resonator coupled to the substrate and comprising;

a fourth coupling point,

a fourth capacitive element electrically coupled between the fourth coupling point and the ground region, and

a fourth inductive element electrically coupled between the fourth coupling point and the ground region;

a first capacitor that electrically couples the first coupling point to the second coupling point;

a second capacitor that electrically couples the second coupling point to the third coupling point; and

a third capacitor that electrically couples the third coupling point to the fourth coupling point;

wherein the filter group delays a signal output at the fourth coupling point relative to a signal input at the first coupling point;

wherein the substrate comprises a first surface, a second surface substantially parallel to the first surface, and a volume between the first and second surfaces;

wherein the first, second, third, and fourth capacitive elements are buried capacitors within the substrate volume;

wherein the first, second, and third capacitors are surface capacitors on the first surface of the substrate;

wherein first and second sides of the first capacitive element are separated by a dielectric layer of the substrate, wherein the dielectric layer comprises hafnium oxide.

2. The time delay filter of claim 1, wherein the first, second, third, and fourth LC resonators are arranged on the substrate in a horseshoe pattern or in a meander pattern.

3. The time delay filter of claim 2, wherein the first inductive element is adjacent the fourth inductive element and the first and fourth inductive elements are magnetically coupled during operation of the time delay filter;

wherein the first and fourth LC resonators are not directly capacitively coupled.

4. The time delay filter of claim 3, further comprising:

a fifth LC resonator coupled to the substrate and comprising;

a fifth coupling point,

a fifth capacitive element electrically coupled between the fifth coupling point and the ground region, and

a fifth inductive element electrically coupled between the fifth coupling point and the ground region;

a sixth LC resonator coupled to the substrate and comprising;

a sixth coupling point,

a sixth capacitive element electrically coupled between the sixth coupling point and the ground region, and

a sixth inductive element electrically coupled between the sixth coupling point and the ground region; and

a fourth capacitor that electrically couples the fourth coupling point to the fifth coupling point; and

a fifth capacitor that electrically couples the fifth coupling point to the sixth coupling point.

5. The time delay filter of claim 4, wherein the first, second, third, fourth, fifth, and sixth LC resonators are arranged on the substrate in a meander pattern.

6. The time delay filter of claim 5, wherein the third inductive element is adjacent the sixth inductive element and the third and sixth inductive elements are magnetically coupled during operation of the time delay filter;

wherein the third and sixth LC resonators are not directly capacitively coupled.

7. The time delay filter of claim 1, wherein the first, second, third, and fourth LC resonators are arranged in a zig-zag pattern.

8. The time delay filter of claim 7, wherein the first inductive element is adjacent the third inductive element and the first and third inductive elements are magnetically coupled during operation of the time delay filter;

wherein the first and third LC resonators are not directly capacitively coupled.

9. The time delay filter of claim 8, wherein the second inductive element is adjacent the fourth inductive element and the second and fourth inductive elements are magnetically coupled during operation of the time delay filter;

wherein the second and fourth LC resonators are not directly capacitively coupled.

10. The time delay filter of claim 1, wherein the first inductive element comprises:

a first conductive region coupled to the first surface of the substrate;

a second conductive region coupled to the second surface of the substrate;

a first via that is electrically coupled to and extends between the first and second conductive region;

a second via that is electrically coupled to and extends between the first conductive region and a first portion of the first capacitive element; and

a third via that is electrically coupled to and extends between the second conductive region and a second portion of the first capacitive element;

wherein the first conductive region, the first via, the second conductive region, the second via, the first capacitive element, and the third via form a loop.

11. A time delay filter comprising:

a substrate comprising a conductive ground region;

a first LC resonator coupled to the substrate and comprising;

a first coupling point,

a first capacitive element electrically coupled between the first coupling point and the ground region, and

a first inductive element electrically coupled between the first coupling point and the ground region;

a second LC resonator coupled to the substrate and comprising;

a second coupling point,

a second capacitive element electrically coupled between the second coupling point and the ground region, and

a second inductive element electrically coupled between the second coupling point and the ground region;

a third LC resonator coupled to the substrate and comprising;

a third coupling point,

a third capacitive element electrically coupled between the third coupling point and the ground region, and

a third inductive element electrically coupled between the third coupling point and the ground region;

a fourth LC resonator coupled to the substrate and comprising;

a fourth coupling point,

a fourth capacitive element electrically coupled between the fourth coupling point and the ground region, and

a fourth inductive element electrically coupled between the fourth coupling point and the ground region;

a fifth LC resonator coupled to the substrate and comprising;

a fifth coupling point,

a fifth capacitive element electrically coupled between the fifth coupling point and the ground region, and

a fifth inductive element electrically coupled between the fifth coupling point and the ground region;

a sixth LC resonator coupled to the substrate and comprising;

a sixth coupling point,

a sixth capacitive element electrically coupled between the sixth coupling point and the ground region, and

a sixth inductive element electrically coupled between the sixth coupling point and the ground region

a first capacitor that electrically couples the first coupling point to the second coupling point;

a second capacitor that electrically couples the second coupling point to the third coupling point; and

a third capacitor that electrically couples the third coupling point to the fourth coupling point;

a fourth capacitor that electrically couples the fourth coupling point to the fifth coupling point; and

a fifth capacitor that electrically couples the fifth coupling point to the sixth coupling point;

wherein the filter group delays a signal output at the sixth coupling point relative to a signal input at the first coupling point;

wherein the first, second, third, fourth, fifth, and sixth LC resonators are arranged on the substrate in a horseshoe pattern;

wherein the substrate comprises a first surface, a second surface substantially parallel to the first surface, and a volume between the first and second surfaces;

wherein the first, second, third, fourth, fifth, and sixth capacitive elements are buried capacitors within the substrate volume;

wherein the first, second, third, fourth, and fifth capacitors are surface capacitors on the first surface of the substrate;

wherein first and second sides of the first capacitive element are separated by a dielectric layer of the substrate, wherein the dielectric layer comprises hafnium oxide.

12. The time delay filter of claim 11, wherein the first inductive element is adjacent the sixth inductive element and the first and sixth inductive elements are magnetically coupled during operation of the time delay filter;

wherein the first and sixth LC resonators are not directly capacitively coupled.

13. The time delay filter of claim 12, wherein the second inductive element is adjacent the fifth inductive element and the second and fifth inductive elements are magnetically coupled during operation of the time delay filter;

wherein the second and fifth LC resonators are not directly capacitively coupled.

14. The time delay filter of claim 11, wherein the first inductive element comprises:

a first conductive region coupled to the first surface of the substrate;

a second conductive region coupled to the second surface of the substrate;

a first via that is electrically coupled to and extends between the first and second conductive region;

a second via that is electrically coupled to and extends between the first conductive region and a first portion of the first capacitive element; and

a third via that is electrically coupled to and extends between the second conductive region and a second portion of the first capacitive element;

wherein the first conductive region, the first via, the second conductive region, the second via, the first capacitive element, and the third via form a loop.