# US 2017/0287618 A1 · Power transformer of the symmetric-asymmetric type with a fully-balanced topology > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0287618 A1 - Document ID: US20170287618A1 - Status: Published application - Kind: A1 - Application number: 15/223,148 - Filed: 2016-07-29 - Published: 2017-10-05 - Earliest claimed: 2016-03-30 - Assignees: STMicroelectronics S.r.l. - Applicants: Stmicroelectronics SA - Inventors: Vincent KNOPIK - Web page: https://patentgrep.com/patent/US20170287618A1 ## CPC - H01F 27/2804: {Printed windings} - H01F 27/29: Terminals; Tapping arrangements {for signal inductances} - H01F 38/14: Inductive couplings - H01F 41/041: {Printed circuit coils (apparatus or processes for manufacturing printed circuits in general H05K3/00)} - H01F 41/10: Connecting leads to windings (making electric connections in general H01R43/00) - H01Q 1/243: {with built-in antennas} - H01Q 1/36: Structural form of radiating elements, e.g. cone, spiral, umbrella; {Particular materials used therewith}(H01Q1/08, H01Q1/14 take precedence) - H01Q 1/48: Earthing means; Earth screens; Counterpoises - H01Q 1/50: Structural association of antennas with earthing switches, lead-in devices or lightning protectors - H01Q 7/00: Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop - H03H 7/42: Networks for transforming balanced signals into unbalanced signals and vice versa, e.g. baluns - H10W 20/497: {Inductive arrangements or effects of, or between, wiring layers} - H01F 27/2809: {on stacked layers} - H01F 27/2819: {Planar transformers with printed windings, e.g. surrounded by two cores and to be mounted on printed circuit} - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) - H03H: IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS (waveguides, resonators, lines or other devices of the waveguide type H01P) - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract A transformer of the symmetric-asymmetric type includes comprising a primary inductive circuit and a secondary inductive circuit formed in a same plane by respective interleaved and stacked metal tracks. A first crossing region includes a pair of connection plates facing one another, with each connection plate having a rectangular shape that is wider than the metal tracks, and diagonally connected to tracks of the secondary inductive circuit. ## Claims ### Claim at position 1 1-14. (canceled) ### Claim 15 A transformer of the symmetric-asymmetric type comprising: a primary inductive circuit and a secondary inductive circuit formed in a same plane by respective interleaved and stacked metal tracks; and at least a first crossing region comprising a pair of connection plates facing one another, with each connection plate having a rectangular shape wider than the metal tracks, and diagonally connected to tracks of said secondary inductive circuit. ### Claim 16 (depends on 15) The transformer according to claim 15, wherein said connection plates are a same size and are aligned in an axis perpendicular to the plane. ### Claim 17 (depends on 15) The transformer according to claim 15, wherein one of said connection plates passes over said other connection plate and comprises two wings each respectively situated on one end of two opposing sides of the rectangular connection plate, with the ends being diagonally opposite and the metal tracks of said secondary inductive circuit being coupled to a lower surface of the two wings. ### Claim 18 (depends on 17) The transformer according to claim 17, wherein each of the wings has a bevel at their connection with the rectangular connection plate. ### Claim 19 (depends on 15) The transformer according to claim 15, wherein said primary and secondary inductive circuits each form a loop having at least two turns that is symmetrical with respect to an axis of the plan. ### Claim 20 (depends on 15) The transformer according to claim 15, wherein said primary and secondary inductive circuits are configured such that, over all of the positions of said secondary inductive circuit at which a coupling with the primary inductive circuit takes place, a sum of distances from one terminal of said primary inductive circuit to the corresponding coupled positions of said primary inductive circuit is equal to a sum of the distances from the other terminal of said primary inductive circuit to the same coupled positions. ### Claim 21 (depends on 15) The transformer according to claim 15, wherein said at least a first crossing region comprises a pair of first metal connection tracks for connecting tracks for said primary inductive circuit, with each first metal connection track crossing one another under the pair of connection plates. ### Claim 22 (depends on 15) The transformer according to claim 15, further comprising a biasing terminal, and at least a second crossing region comprising a pair of second metal connection tracks for connecting tracks of said primary inductive circuit, with each second metal connection track crossing one another on either side of the biasing terminal, and with one of the second metal connection tracks passing above the biasing terminal and the other second metal connection track passing underneath. ### Claim 23 (depends on 22) The transformer according to claim 22, wherein said secondary inductive circuit comprises a pair of terminals, and wherein the biasing terminal is configured as a rectangular plate connected to a mid-point of said secondary inductive circuit and is adjacent the pair of terminals of said secondary inductive circuit. ### Claim 24 (depends on 15) The transformer according to claim 15, wherein the metal tracks of said primary inductive circuit are narrower than the metal tracks of said secondary inductive circuit over at least a portion of said primary inductive circuit. ### Claim 25 (depends on 15) The transformer according to claim 15, further comprising a semiconductor substrate, with said primary and secondary inductive circuits being formed on said semiconductor substrate. ### Claim 26 A device comprising: an antenna; a processor; and a transformer coupled between said antenna and said processor, and comprising a primary inductive circuit and a secondary inductive circuit formed in a same plane by respective interleaved and stacked metal tracks, and at least a first crossing region comprising a pair of connection plates facing one another, with each connection plate having a rectangular shape that is wider than the metal tracks, and diagonally connected to tracks of said secondary inductive circuit. ### Claim 27 (depends on 26) The device according to claim 26, wherein said connection plates are a same size and are aligned in an axis perpendicular to the plane. ### Claim 28 (depends on 26) The device according to claim 26, wherein one of said connection plates passes over said other connection plate and comprises two wings each respectively situated on one end of two opposing sides of the rectangular connection plates, with the ends being diagonally opposite and the metal tracks of said secondary inductive circuit being coupled to a lower surface of the two wings. ### Claim 29 (depends on 28) The device according to claim 28, wherein each of the wings has a bevel at their connection with the rectangular connection plate. ### Claim 30 (depends on 26) The device according to claim 26, wherein said primary and secondary inductive circuits each form a loop having at least two turns that is symmetrical with respect to an axis of the plan. ### Claim 31 (depends on 26) The device according to claim 26, wherein said primary and secondary inductive circuits are configured such that, over all of the positions of said secondary inductive circuit at which a coupling with the primary inductive circuit takes place, a sum of distances from one terminal of said primary inductive circuit to the corresponding coupled positions of said primary inductive circuit is equal to a sum of the distances from the other terminal of said primary inductive circuit to the same coupled positions. ### Claim 32 (depends on 26) The device according to claim 26, wherein said at least a first crossing region comprises a pair of first metal connection tracks for connecting tracks for said primary inductive circuit, with each first metal connection track crossing one another under the pair of connection plates. ### Claim 33 (depends on 26) The device according to claim 26, further comprising a biasing terminal, and at least a second crossing region comprising a pair of second metal connection tracks for connecting tracks of said primary inductive circuit, with each second metal connection track crossing one another on either side of the biasing terminal, and with one of the second metal connection tracks passing above the biasing terminal and the other second metal connection track passing underneath. ### Claim 34 (depends on 26) The device according to claim 26, wherein the metal tracks of said primary inductive circuit are narrower than the metal tracks of said secondary inductive circuit over at least a portion of said primary inductive circuit. ### Claim 35 (depends on 26) The device according to claim 26 wherein said antenna, said processor, and said transformer are configured so that the device is at least one of a telecommunications system, a cellular mobile telephone and a tablet. ### Claim 36 A method for making a transformer of the symmetric-asymmetric type comprising: forming a primary inductive circuit and a secondary inductive circuit in a same plane by respective interleaved and stacked metal tracks; and forming at least a first crossing region comprising a pair of connection plates facing one another, with each connection plate having a rectangular shape that is wider than the metal tracks, and diagonally connected to tracks of the secondary inductive circuit. ### Claim 37 (depends on 37) The method according to claim 37, wherein the connection plates are a same size and are aligned in an axis perpendicular to the plane. ### Claim 38 (depends on 37) The method according to claim 37, wherein one of the connection plates passes over the other connection plate and comprises two wings each respectively situated on one end of two opposing sides of the rectangular connection plate, with the ends being diagonally opposite and the metal tracks of the secondary inductive circuit being coupled to a lower surface of the two wings. ### Claim 39 (depends on 39) The method according to claim 39, wherein each of the wings has a bevel at their connection with the rectangular connection plate. ### Claim 40 (depends on 37) The method according to claim 37, wherein the primary and secondary inductive circuits each form a loop having at least two turns that is symmetrical with respect to an axis of the plan. ### Claim 41 (depends on 37) The method according to claim 37, wherein the primary and secondary inductive circuits are configured such that, over all of the positions of the secondary inductive circuit at which a coupling with the primary inductive circuit takes place, a sum of distances from one terminal of the primary inductive circuit to the corresponding coupled positions of the primary inductive circuit is equal to a sum of the distances from the other terminal of the primary inductive circuit to the same coupled positions.