IP Library Granted Patent US 12,418,085
Granted Patent B2
US 12,418,085 · App. 17/965,680 · Granted Sep 16, 2025

Circulator design and methods of fabricating the circulator

Inventors: Niels Husted Kirkeby (Santa Ana, CA); Brady Fitzgerald (Santa Ana, CA); Michael Len (Santa Ana, CA); Thomas Lingel (Santa Ana, CA); Mark Bowyer (Santa Ana, CA); Benton O'Neil (Santa Ana, CA)
Assignee: TTM Technologies, Inc.
H01P1/38H01P1/387H01P11/00
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Quick Facts
Patent No.
US 12,418,085
App. No.
17/965,680
Granted
Sep 16, 2025
Kind
B2
Abstract

A circulator for radio frequency is provided. The circulator may include a ferrite stripline assembly, which includes a first ferrite layer, a second ferrite layer over the first ferrite layer, and a junction circuit between the first ferrite layer and the second ferrite layer. The circulator may also include a magnet over the second ferrite layer for providing magnetic bias.

Claims (40)

1. A circulator for radio frequency, the circulator comprising:

a ferrite stripline assembly comprising:

a first ferrite layer;

a second ferrite layer disposed over a first side of the first ferrite layer;

a junction circuit between the first ferrite layer and the second ferrite layer, wherein the junction circuit comprises a first circuit formed on the first side of the first ferrite layer, a second circuit formed on a second side of the second ferrite layer;

a first ground layer contacting the first ferrite layer and opposite to the junction circuit;

a magnet over a first side of the second ferrite layer for providing magnetic bias;

a second ground layer between the second ferrite layer and the magnet, the second ground layer opposite to the junction circuit; and

one or more perimeter grounds located on a respective perimeter of the first ferrite layer and the second ferrite layer, wherein the one or more perimeter grounds are integrated with the first ground layer and the second ground layer.

2. The circulator of claim 1 , wherein the ferrite stripline assembly further comprises a metal seed layer over surfaces of each of the first ferrite layer and the second ferrite layer.

3. The circulator of claim 2 , wherein the metal seed layer is between the junction circuit and the first ferrite layer and/or between the junction circuit and the second ferrite layer.

4. The circulator of claim 1 , wherein the junction circuit comprises an intermetallic bond formed between the first circuit and the second circuit.

5. The circulator of claim 1 , wherein the first and second ferrite layers are attached by an intermetallic bond or a paste.

6. The circulator of claim 5 , wherein the intermetallic bond comprises one of indium, preform of solder, or solder dots.

7. The circulator of claim 1 , further comprising an input port and an output port coupled to a perimeter of the first ferrite layer.

8. The circulator of claim 7 , further comprising one or more perimeter port leads coupled to the perimeter of the first ferrite layer to connect the junction circuit to the input port and the output port on a second side of the first ferrite opposite to the junction circuit.

9. The circulator of claim 1 , further comprising a pole piece between the magnet and the second ferrite layer to form a magnetic bias assembly comprising the magnet and the pole piece.

10. The circulator of claim 1 , further comprising clips forming a magnetic return path and encapsulating the ferrite stripline assembly and the magnet.

11. A circulator for radio frequency, the circulator comprising:

a ferrite stripline assembly comprising:

a first ferrite layer;

a second ferrite layer disposed over the first ferrite layer;

a junction circuit between the first ferrite layer and the second ferrite layer;

a metal seed layer over all surfaces of each of the first ferrite layer and the second ferrite layer; and

a magnet over the second ferrite layer for providing magnetic bias.

12. The circulator of claim 11 , further comprising an input port and an output port coupled to a perimeter of the first ferrite layer.

13. The circulator of claim 12 , further comprising one or more perimeter port leads coupled to the perimeter of the first ferrite layer to connect the junction circuit to the input port and the output port on the bottom of the first ferrite.

14. The circulator of claim 12 , wherein the first and second ferrite layers are attached by an intermetallic bond or a paste.

15. The circulator of claim 14 , wherein the intermetallic bond comprises one of indium, preform of solder, or solder dots.

16. A circulator for radio frequency, the circulator comprising:

a ferrite stripline assembly comprising:

a first ferrite layer;

a second ferrite layer disposed over the first ferrite layer, wherein the first and second ferrite layers are attached by an intermetallic bond or a paste;

a junction circuit between the first ferrite layer and the second ferrite layer; and

a magnet over the second ferrite layer for providing magnetic bias.

17. The circulator of claim 16 , wherein the intermetallic bond comprises one of indium, preform of solder, or solder dots.

18. The circulator of claim 16 , further comprising an input port and an output port coupled to a perimeter of the first ferrite layer.

19. The circulator of claim 18 , further comprising one or more perimeter port leads coupled to the perimeter of the first ferrite layer to connect the junction circuit to the input port and the output port on the bottom of the first ferrite layer.

20. The circulator of claim 16 , wherein the ferrite stripline assembly further comprises a metal seed layer over surfaces of each of the first ferrite layer and the second ferrite layer.

21. The circulator of claim 20 , wherein the metal seed layer is between the junction circuit and the first ferrite layer and/or between the junction circuit and the second ferrite layer.

Assignments (6)
RELEASE OF SECURITY INTEREST IN PATENTS PREVIOUSLY RECORDED AT REEL/FRAME (063804/0702) Recorded Jun 2, 2026
From: JPMORGAN CHASE BANK, N.A., AS ADMINISTRATIVE AGENT
To: TELEPHONICS CORPORATION; TTM TECHNOLOGIES, INC.; TTM TECHNOLOGIES NORTH AMERICA, LLC
Reel/Frame 075679/0852 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 21, 2025
From: KIRKEBY, NIELS HUSTED; FITZGERALD, BRADY; LEN, MICHAEL; LINGEL, THOMAS; BOWYER, MARK; O'NEIL, BENTON
To: TTM TECHNOLOGIES INC.
Reel/Frame 071773/0502 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 19, 2025
From: KIRKEBY, NIELS HUSTED; FITZGERALD, BRADY; LEN, MICHAEL; LINGEL, THOMAS; BOWYER, MARK; O'NEIL, BENTON
To: TTM TECHNOLOGIES INC.
Reel/Frame 070255/0514 →
PATENT SECURITY AGREEMENT (ABL) Recorded May 30, 2023
From: TELEPHONICS CORPORATION; TTM TECHNOLOGIES, INC.; TTM TECHNOLOGIES NORTH AMERICA, LLC
To: JPMORGAN CHASE BANK, N.A., AS ADMINISTRATIVE AGENT
Reel/Frame 063804/0702 →
PATENT SECURITY AGREEMENT (TERM LOAN) Recorded May 30, 2023
From: TELEPHONICS CORPORATION; TTM TECHNOLOGIES, INC.; TTM TECHNOLOGIES NORTH AMERICA, LLC
To: JPMORGAN CHASE BANK, N.A., AS ADMINISTRATIVE AGENT
Reel/Frame 063804/0745 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 20, 2023
From: KIRKEBY, NIELS HUSTED; FITZGERALD, BRADY; LEN, MICHAEL; LINGEL, THOMAS; BOWYER, MARK; O'NEIL, BENTON
To: TTM TECHNOLOGIES INC.
Reel/Frame 062440/0129 →
Continuity (2)
Provisional Application 63270456 · Oct 21, 2021
Related Publication 20230125826A1 · Apr 27, 2023
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