# US 2017/0288386 A1 · Power supply with current limit on individual conductors > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0288386 A1 - Document ID: US20170288386A1 - Status: Published application - Kind: A1 - Application number: 15/506,698 - Filed: 2014-08-29 - Published: 2017-10-05 - Earliest claimed: 2014-08-29 - Assignees: Apple Inc. - Applicants: Apple Inc. - Inventors: Paul J. Costa; Bharat K. Patel; Neal V. Cecil; Timur O. Starobinets; Ruenjou Lu; Dane Oleson; Fei Ni - Web page: https://patentgrep.com/patent/US20170288386A1 ## CPC - H02H 3/08: responsive to excess current (responsive to abnormal temperature caused by excess current H02H5/04) - H02H 3/22: of short duration, e.g. lightning - H02H 7/125: for rectifiers - H02H 7/22: for distribution gear, e.g. bus-bar systems; for switching devices {(detecting mechanical or electrical defects in gas-insulated switchgears H02B13/065)} - H02H 7/226: {for wires or cables, e.g. heating wires} - H02H 7/228: {for covered wires or cables} - H02J 1/00: Circuit arrangements for DC mains or DC distribution networks - H02J 13/00: Circuit arrangements for providing remote monitoring or remote control of equipment in a power distribution network - H02J 13/1323: {using optical fibres} - H02J 13/36: specially adapted for protection systems - Y02B 90/20: Smart grids as enabling technology in buildings sector (smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00) - Y04S 20/00: Management or operation of end-user stationary applications or the last stages of power distribution; Controlling, monitoring or operating thereof - H02H: EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS (indicating or signalling undesired working conditions G01R, e.g. G01R31/00, G08B; locating faults along lines G01R31/08; emergency protective devices H01H) - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS - Y04S: SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS ## Abstract Circuits, methods, and apparatus that may provide power supply voltages in a safe and reliable manner that meets safety and regulatory concerns and does not exceed physical limitations of cables and other circuits and components used to provide the power supply voltages. One example may provide a cable having a sufficient number of conductors to provide power without exceeding a maximum current density for the conductors. Another example may provide a cable having more than the sufficient number of conductors in order to provide an amount of redundancy. Current sense circuits may be included for one or more conductors. When an excess current is sensed, a power source in the power supply may be shut down, the power source may be disconnected from one or more conductors, or both events may occur. ## Claims ### Claim 1 A power supply comprising: a connector; a power source; a first current path between the power source and a first contact of the connector; a second current path between the power source and a second contact of the connector; a first current sense circuit to sense a first current in the first current path, wherein in response to sensing a current above a first level, the first current sense circuit provides a first signal to disconnect the power source from the first current path and the second current path; a second current sense circuit to sense a second current in the second current path, wherein in response to sensing a current above a second level, the second current sense circuit provides a second signal to disconnect the power source from the first current path and the second current path. ### Claim 2 (depends on 1) The power supply of claim 1 wherein the power source comprises an AC-to-DC converter. ### Claim 3 (depends on 1) The power supply of claim 1 further comprising a switch between the power source and the first current path and the second current path. ### Claim 4 (depends on 3) The power supply of claim 3 further comprising a first voltage transient suppressant circuit coupled to the power source and the switch and a second voltage transient suppressant circuit coupled to the switch and the first and second current paths. ### Claim 5 (depends on 4) The power supply of claim 4 wherein the first voltage transient suppressant circuit comprises a first voltage transient suppressant diode and a first capacitor and the second voltage transient suppressant circuit comprises a second voltage transient suppressant diode and a second capacitor. ### Claim 6 (canceled) ### Claim 7 (canceled) ### Claim 8 (depends on 4) The power supply of claim 4 wherein in response to sensing a current above the first level, the first current sense circuit provides the first signal to open the switch between the power source and the first current path and the second current path thereby disconnecting the power source from the first current path and the second current path, and wherein in response to sensing a current above the second level, the second current sense circuit provides the second signal to open the switch between the power source and the first current path and the second current path thereby disconnecting the power source from the first current path and the second current path. ### Claim 9 (depends on 8) The power supply of claim 8 wherein the first current sense circuit senses a current level in the first current path by measuring a voltage across a resistor in the first current path and wherein the second current sense circuit senses a current level in the second current path by measuring a voltage across a resistor in the second current path. ### Claim 10 (depends on 9) The power supply of claim 9 further comprising: a third current path between a third contact in the connector and ground; a fourth current path between a fourth contact in the connector and ground; a third current sense circuit to sense a third current in the third current path, wherein in response to sensing a current above a third level, the third current sense circuit provides a third signal to disconnect the power source from the first current path and the second current path; a fourth current sense circuit to sense a fourth current in the fourth current path, wherein in response to sensing a current above a fourth level, the fourth current sense circuit provides a fourth signal to disconnect the power source from the first current path and the second current path. ### Claim 11 (canceled) ### Claim 12 (depends on 1) The power supply of claim 1 wherein the connector is a connector receptacle. ### Claim 13 A power supply comprising: a power source; a first switch coupled to an output of the power source; a first resistor having a first terminal coupled to the first switch; a second resistor having a first terminal coupled to the first switch; a first current sense circuit having a first input coupled to the first terminal of the first resistor, a second input coupled to a second terminal of the first resistor, and an output coupled to a control input of the first switch; and a second current sense circuit having a first input coupled to the first terminal of the second resistor, a second input coupled to a second terminal of the second resistor, and an output coupled to a control input of the first switch. ### Claim 14 (depends on 13) The power supply of claim 13 further comprising a connector having a first contact coupled to the second terminal of the first resistor and a second contact coupled to the second terminal of the second resistor. ### Claim 15 (depends on 14) The power supply of claim 14 further comprising: a third resistor having a first terminal coupled to a third contact in the connector and a second terminal coupled to ground; a fourth resistor having a first terminal coupled to a fourth contact in the connector and a second terminal coupled to ground; a third current sense circuit having a first input coupled to the first terminal of the third resistor, a second input coupled to ground, and an output coupled to a control input of the first switch; and a fourth current sense circuit having a first input coupled to the first terminal of the fourth resistor, a second input coupled to ground, and an output coupled to a control input of the first switch. ### Claim 16 (canceled) ### Claim 17 (depends on 14) The power supply of claim 14 wherein the current sense path comprises a low-pass filter in series with a comparator. ### Claim 18 (depends on 17) The power supply of claim 17 further comprising a storage circuit in series with the comparator. ### Claim 19 (depends on 18) The power supply of claim 18 wherein the storage circuit is a set-reset latch. ### Claim 20 (depends on 14) The power supply of claim 14 further comprising a first fuse between the first switch and the first resistor and a second fuse between the first switch and the second switch. ### Claim 21 (depends on 20) The power supply of claim 20 further comprising a third fuse between the first fuse and the first switch and the second fuse and the second switch. ### Claim 22 A method of using a power supply to provide power over a cable, the method comprising: detecting that a first connector at a first end of the cable is properly connected to a second connector; and providing a first power supply voltage over the cable to a first circuit coupled to the second connector; and receiving a response from the first circuit; then providing a second power supply voltage over the cable, otherwise not providing the second power supply voltage. ### Claim 23 (depends on 22) The method of claim 22 wherein the second power supply voltage is provided over a first conductor and a second conductor, the method further comprising, while providing the second power supply voltage over the cable: detecting a first current level in the first conductor; detecting a second current level in the second conductor; in response to either the first current level or the second current level being higher than a first threshold, not providing the second power supply voltage over the cable, otherwise continuing to provide the second power supply voltage over the cable. ### Claim 24 (canceled) ### Claim 25 (depends on 23) The method of claim 23 wherein the second connector is housed in an electronic device powered by the power supply.