# US 12,372,550 B2 · Isolated probe tip > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,372,550 B2 - Document ID: US12372550B2 - Status: Granted - Kind: B2 - Application number: 17/730,096 - Filed: 2022-04-26 - Published: 2022-11-03 - Granted: 2025-07-29 - Earliest claimed: 2021-04-29 - Applicants: Tektronix, Inc. - Inventors: Daniel G. Knierim; Josiah A. Bartlett; Andrew W. Rusinek; David Thomas Engquist - Web page: https://patentgrep.com/patent/US12372550B2 ## CPC - G01R 1/06711: {Probe needles; Cantilever beams; "Bump" contacts; Replaceable probe pins} - G01R 1/06738: {related to tip portion} - G01R 31/2886: {Features relating to contacting the IC under test, e.g. probe heads; chucks (G01R31/2865 takes precedence, test connections, e.g. test sockets, or probes per se, G01R1/04 or G01R1/06)} - H05K 9/0069: {Methods for measuring the shielding efficiency; Apparatus therefor; Isolation container for testing} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract A probe tip for an isolated probe having a triaxial cable has a conductive probe tip interface at one end of the cable, a signal conductor, the signal conductor traversing a length of the cable and electrically connected to the conductive probe tip interface, a reference conductor surrounding the signal conductor along the length of the cable, a shield conductor surrounding the reference conductor at least along the length of the cable, the shield conductor and the reference conductor electrically connected at ends of the probe tip, a first insulator between the signal conductor and the reference conductor along the length of the cable, a second insulator between the reference conductor and the shield conductor along the length of the cable, and high magnetic permeability material inside the shield conductor. A method of manufacturing a tip for an isolated probe having a triaxial cable includes accessing a shield conductor of the triaxial cable, inserting a high magnetic permeability material between the shield conductor and a reference conductor in the triaxial cable, electrically connecting the shield conductor to the reference conductor. A triaxial cable has a signal conductor, the signal conductor traversing a length of the cable, a reference conductor surrounding the signal conductor along the length of the cable, a shield conductor surrounding the reference conductor along the length of the cable, the shield conductor and the reference conductor electrically connected at ends of the cable, a first insulator between the signal conductor and the reference conductor along the length of the cable, a second insulator between the reference conductor and the shield conductor along the length of the cable, and high magnetic permeability material inside the shield conductor. ## Claims ### Claim 1 A probe tip for an isolated probe having a triaxial cable, comprising: a conductive probe tip interface at one end of the cable; a signal conductor, the signal conductor traversing a length of the cable and electrically connected to the conductive probe tip interface; a reference conductor surrounding the signal conductor along the length of the cable; a shield conductor surrounding the reference conductor at least along the length of the cable, the shield conductor and the reference conductor electrically connected at ends of the probe tip; a first insulator between the signal conductor and the reference conductor along the length of the cable; a second insulator between the reference conductor and the shield conductor along the length of the cable; and high magnetic permeability material inside the shield conductor. ### Claim 2 (depends on 1) The probe tip as claimed in claim 1, wherein the high magnetic permeability material comprises a common mode choke at one or both ends of the cable, and the shield conductor further comprises a conductive shell housing the common mode choke. ### Claim 3 (depends on 1) The probe tip as claimed in claim 1, further comprising high magnetic permeability material outside of the shield conductor. ### Claim 4 (depends on 1) The probe tip as claimed in claim 1, further comprising a printed circuit board connected to an end of the cable opposite the conductive probe tip interface. ### Claim 5 (depends on 4) The probe tip as claimed in claim 4, wherein the printed circuit board includes a common mode choke. ### Claim 6 (depends on 1) The probe tip as claimed in claim 1, wherein the high magnetic permeability material comprises a ferrite. ### Claim 7 (depends on 1) The probe tip as claimed in claim 1, wherein the high magnetic permeability material inside the shield conductor lies between the shield conductor and the reference conductor. ### Claim 8 (depends on 1) The probe tip as claimed in claim 1, wherein the high magnetic permeability material inside the shield conductor is integrated into material of the second insulator. ### Claim 9 A method of manufacturing a tip for an isolated probe having a triaxial cable, comprising: accessing a shield conductor of the triaxial cable, wherein the triaxial cable includes a signal conductor, a first insulator surrounding the signal conductor, a reference conductor surrounding the first insulator, a second insulator surrounding the reference conductor, and the shield conductor surrounding the second insulator; inserting a high magnetic permeability material between the shield conductor and the reference conductor in the triaxial cable; and electrically connecting the shield conductor to the reference conductor. ### Claim 10 (depends on 9) The method of manufacturing as claimed in claim 9, further comprising placing high magnetic permeability material outside the shield conductor. ### Claim 11 (depends on 9) The method of manufacturing as claimed in claim 9, wherein accessing the shield conductor comprises unbraiding the shield conductor at ends of the cable and wrapping the shield conductor over the high magnetic permeability material before electrically connecting the shield conductor to the reference conductor. ### Claim 12 (depends on 9) The method of manufacturing as claimed in claim 9, wherein accessing the shield conductor comprises removing a portion of the shield conductor at ends of the cable, and the method further comprises: placing a braid having a larger diameter than the shield conductor at each end of the cable to hold the high magnetic permeability material; and soldering the larger diameter braid to the shield conductor. ### Claim 13 (depends on 9) The method of manufacturing as claimed in claim 9, wherein: accessing the shield conductor comprises: coating an end of the cable with an anti-fraying material; trimming the anti-fraying material; and creating openings in an end of the cable, the openings exposing the shield conductor; inserting the high magnetic permeability material comprises sliding the high magnetic permeability material into the openings against the shield conductor; and removing the anti-fraying material. ### Claim 14 (depends on 13) The method as claimed in claim 13, wherein creating openings comprises using wedges of a material other than the high magnetic permeability material to expand the shield conductor. ### Claim 15 A triaxial cable, comprising: a signal conductor, the signal conductor traversing a length of the cable; a reference conductor surrounding the signal conductor along the length of the cable; a shield conductor surrounding the reference conductor along the length of the cable, the shield conductor and the reference conductor electrically connected at ends of the cable; a first insulator between the signal conductor and the reference conductor along the length of the cable; a second insulator between the reference conductor and the shield conductor along the length of the cable; and high magnetic permeability material inside the shield conductor. ### Claim 16 (depends on 15) The cable as claimed in claim 15, further comprising high magnetic permeability material outside of the shield conductor. ### Claim 17 (depends on 15) The cable as claimed in claim 15, wherein the high magnetic permeability material comprises a common mode choke at one or both ends of the cable, the cable further comprising a conductive metal shell electrically connected to the shield conductor. ### Claim 18 (depends on 15) The cable as claimed in claim 15, wherein the high magnetic permeability material comprises a ferrite. ### Claim 19 (depends on 15) The cable as claimed in claim 15, wherein the high magnetic permeability material inside the shield conductor lies between the shield conductor and the reference conductor. ### Claim 20 (depends on 15) The cable as claimed in claim 15, wherein the high magnetic permeability material inside the shield conductor is integrated into material of the second insulator.