# US 10,121,584 B2 · High power density printed circuit board (PCB) embedded inductors > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,121,584 B2 - Document ID: US10121584B2 - Status: Granted - Kind: B2 - Application number: 15/917,931 - Filed: 2018-03-12 - Published: 2018-07-19 - Granted: 2018-11-06 - Earliest claimed: 2015-11-24 - Assignees: The University of North Carolina at Charlotte - Applicants: The University of North Carolina at Charlotte - Inventors: Mehrdad Biglarbegian; Neel Mayur Shah; Babak Parkhideh - Web page: https://patentgrep.com/patent/US10121584B2 ## CPC - H01F 27/2804: {Printed windings} - H01F 17/0013: {with stacked layers} - H02M 1/126: {using passive filters} - H05K 1/165: {incorporating printed inductors} - H05K 3/0005: {for designing circuits by computer} - H01F 2017/004: {with the coil helically wound around an axis without a core} - H01F 2017/0073: {with a special conductive pattern, e.g. flat spiral} - H02M 7/5387: in a bridge configuration - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract Devices, systems, and methods of manufacture relating to PCB embedded inductors are described in the present disclosure. Namely, an example device includes a substrate having an upper surface and an opposing lower surface. The device also includes a plurality of upper conductors disposed along the upper surface and a plurality of lower conductors disposed along the lower surface. The upper conductors and the lower conductors are radially disposed about a central axis. Each of the upper conductors and the lower conductors includes a petal shape. A distance between adjacent upper conductors is less than a width of each upper conductor and a distance between adjacent lower conductors is less than a width of each lower conductor. The device also includes a plurality of through-substrate conductors connecting respective upper conductors to respective lower conductors so as to form a series electrical connection. The series electrical connection includes a toroid configuration. ## Claims ### Claim 1 A device comprising: a substrate having an upper surface and an opposing lower surface; a plurality of upper conductors disposed along the upper surface, wherein the plurality of upper conductors is radially disposed about a central axis, wherein a distance between adjacent upper conductors is less than a width of each upper conductor; a plurality of lower conductors disposed along the lower surface, wherein the plurality of lower conductors is radially disposed about the central axis, wherein a distance between adjacent lower conductors is less than a width of each lower conductor; and a plurality of through-substrate conductors connecting respective upper conductors to respective lower conductors so as to form a series electrical connection, wherein the series electrical connection comprises a toroid configuration. ### Claim 2 (depends on 1) The device of claim 1, wherein the toroid configuration comprises a plurality of turns about a reference circle that is defined along a reference plane between the upper surface and the lower surface. ### Claim 3 (depends on 1) The device of claim 1, wherein a thickness of the substrate is less than about 1.6 millimeters. ### Claim 4 (depends on 1) The device of claim 1, wherein a diameter of the device is no greater than about 60 millimeters. ### Claim 5 (depends on 1) The device of claim 1, wherein an area of the device is less than about 3000 mm2. ### Claim 6 (depends on 1) The device of claim 1, wherein the toroid configuration comprises a plurality of turns and the plurality of turns is at least one of 8, 13, or 26. ### Claim 7 (depends on 1) The device of claim 1, wherein a quality factor of the device is at least 300. ### Claim 8 (depends on 1) The device of claim 1, further comprising: a heat sink coupled to at least one of the upper surface or one of the plurality of upper conductors. ### Claim 9 A device comprising: a plurality of upper conductors disposed along an upper surface of a substrate, wherein the plurality of upper conductors is radially disposed about a central axis, wherein a trace clearance between adjacent upper conductors is less than a width of each upper conductor, wherein the substrate comprises a printed circuit board (PCB); a plurality of lower conductors disposed along a lower surface of the substrate, wherein the lower substrate is disposed opposite the upper surface, wherein the plurality of lower conductors is radially disposed about the central axis, wherein a trace clearance between adjacent lower conductors is less than a width of each lower conductor; and a plurality of through-substrate conductors connecting respective upper conductors to respective lower conductors so as to form a series electrical connection, wherein the series electrical connection comprises a toroid configuration, wherein the toroid configuration comprises a plurality of turns about a reference circle that is defined along a reference plane between the upper surface and the lower surface. ### Claim 10 (depends on 9) The device of claim 9, wherein the plurality of lower conductors are disposed such that an inner portion of a given upper conductor overlaps an inner portion of a first lower conductor and an outer portion of the given upper conductor overlaps an outer portion of a second lower conductor. ### Claim 11 (depends on 9) The device of claim 9, wherein each lower conductor has an inner edge located adjacent to the central axis and an outer edge located opposite the central axis. ### Claim 12 (depends on 11) The device of claim 11, wherein the inner edge is narrower than the outer edge. ### Claim 13 (depends on 9) The device of claim 9, wherein a given lower conductor is connected to two different upper conductors to form the series electrical connection. ### Claim 14 (depends on 9) The device of claim 9, wherein the toroid configuration comprises connection of the respective upper conductors to the respective lower conductors in a clockwise arrangement. ### Claim 15 (depends on 9) The device of claim 9, wherein the toroid configuration comprises connection of the respective upper conductors to the respective lower conductors in a counter-clockwise arrangement. ### Claim 16 A method for designing a PCB-embedded inductor, the method comprising: adjusting an outer diameter of the inductor and a number of turns of the inductor based on predetermined physical constraints and predetermined performance specifications, wherein the inductor comprises: a plurality of upper conductors disposed along an upper surface of a substrate, wherein the plurality of upper conductors is radial disposed about a central axis; a plurality of lower conductors disposed along a lower surface of the substrate, wherein the lower surface is disposed opposite the upper surface, wherein the plurality of lower conductors is radially disposed about the central axis; and a plurality of through-substrate conductors connecting respective upper conductors to respective lower conductors so as to form a series electrical connection, wherein the series electrical connection comprises a toroid configuration; adjusting one or more attributes of the inductor including (i) a trace clearance, (ii) a thickness of at least one of the upper conductor or the lower conductor, (iii) a diameter of the through-substrate conductors, and (iv) a number of through-substrate conductors, wherein the trace clearance comprises a distance between adjacent conductors; determining a plurality of device performance metrics, based on the adjusted attributes of the inductor; determining, based on the device performance metrics being above a plurality of device requirements, that the inductor should be fabricated; and fabricating the inductor according to the adjusted attributes. ### Claim 17 (depends on 16) The method of claim 16, wherein adjusting the one or more attributes of the inductor comprises adjusting the trace clearance, wherein the trace clearance comprises a distance between adjacent conductors. ### Claim 18 (depends on 16) The method of claim 16, further comprising: subsequent to adjusting the outer diameter and the number of turns, determining whether an inductance of the inductor is greater than a threshold inductance value; and based on the inductance of the inductor being greater than the threshold inductance value, continuing the fabrication process. ### Claim 19 (depends on 16) The method of claim 16, further comprising: subsequent to adjusting the trace clearance, determining whether an inductance of the inductor is greater than a threshold inductance value; and based on the inductance of the inductor being greater than the threshold inductance value, continuing the fabrication process. ### Claim 20 (depends on 16) The method of claim 16, wherein determining the plurality of device performance metrics comprises conducting at least one finite element analysis.