# US 9,438,038 B1 · Power supply fast turn-on and increased hold-up time within an electrical device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,438,038 B1 - Document ID: US9438038B1 - Status: Granted - Kind: B1 - Application number: 13/430,334 - Filed: 2012-03-26 - Granted: 2016-09-06 - Earliest claimed: 2012-03-26 - Assignees: Juniper Networks, Inc. - Applicants: Philip Richard Quaife - Inventors: Philip Richard Quaife - Web page: https://patentgrep.com/patent/US9438038B1 ## CPC - H02J 1/102: being switching converters (H02J1/108, H02J1/12 take precedence) - H02J 7/345: {using capacitors as storage or buffering devices} - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY ## Abstract This disclosure is directed to techniques for providing supply power to components of an electronics system, such as components of a networking device. According to these techniques, a power supply system charges a bulk capacitance of a power supply unit when the power supply unit is selectively disabled (e.g., disconnected). In this manner, when the power supply unit is again enabled, the power supply unit may provide supply power to components of the networking device faster in comparison to other techniques. In addition the power supply does not use any input power and therefore does not produce any heat loss while it is disconnected, thus saving otherwise wasted energy. ## Claims ### Claim 1 A method comprising: receiving a source power supply at a first power supply unit configured to supply power to at least one electronic component, wherein the first power supply unit is one of a plurality of power supply units configured to supply power to the at least one electronic component in parallel by a power distribution bus; receiving, at a power supply controller coupled to the first power supply unit, a disable signal that indicates the first power supply unit should be disconnected such that the first power supply unit does not supply power to the at least one electronic component; disconnecting, in response to the disable signal, the first power supply unit from the source power supply such that the first power supply unit does not supply power to the at least one electronic component; and charging, in response to the disable signal, a bulk capacitance of the first power supply unit to a predetermined level while the first power supply unit is disconnected from the source power supply by delivering power from a second power supply unit of the plurality of power supply units to the bulk capacitance of the first power supply unit via the power distribution bus while the second power supply unit supplies power to the at least one electronic component. ### Claim 2 (depends on 1) The method of claim 1, further comprising: using an ORing transistor coupled to an output of the first power supply to charge the bulk capacitance. ### Claim 3 (depends on 2) The method of claim 2, further comprising: receiving power to charge the bulk capacitance of the first power supply unit via an output of the ORing transistor that is coupled to the second power supply unit. ### Claim 4 (depends on 3) The method of claim 3, wherein using the ORing transistor to charge the bulk capacitance comprises reverse-biasing the ORing transistor such that power from the second power supply unit charges the bulk capacitance. ### Claim 5 (depends on 1) The method of claim 1, wherein disconnecting, in response to the disable signal, the first power supply unit from source power supply comprises: disconnecting via opening a switch coupled between the first power supply unit and the source power supply. ### Claim 6 (depends on 1) The method of claim 1, further comprising: receiving, at the power supply controller, an enable signal that indicates the first power supply unit should be connected to the at least one electronic component; and connecting, in response to receiving the enable signal, the first power supply unit to the source power supply. ### Claim 7 (depends on 6) The method of claim 6, wherein charging, in response to the disable signal, the bulk capacitance of the first power supply unit to the predetermined level causes the at least one electronic component to be powered by the first power supply unit faster once connected to the source power supply in response to the receiving the enable signal than if the bulk capacitance of the first power supply unit had not been charged to the predetermined level. ### Claim 8 (depends on 1) The method of claim 1, wherein the predetermined level comprises a voltage level. ### Claim 9 A networking device, comprising: a power supply system comprising: a first power supply unit and a second power supply unit configured to supply power in parallel to at least one electronic component via a power distribution bus; and a control unit coupled to the power supply unit configured to: receive a disable signal that indicates the first power supply unit should be disconnected from the at least one electronic component such that the first power supply unit does not supply power to the at least one electric component; disconnect, in response to the disable signal, the first power supply unit from a source power supply such that the first power supply unit does not supply power to the at least one electronic component; and charge, in response to the disable signal, a bulk capacitance of the first power supply unit to a predetermined level while the first power supply unit is disconnected from the source power supply by delivering power from the second power supply unit to the bulk capacitance of the first power supply unit via the power distribution bus while the second power supply unit supplies power to the at least one electronic component. ### Claim 10 (depends on 9) The device of claim 9, further comprising: an ORing transistor coupled to the first power supply unit and the control unit, wherein the control unit uses the ORing transistor to charge the bulk capacitance to the predetermined level. ### Claim 11 (depends on 10) The device of claim 10, wherein the control unit uses power received via an output of the ORing transistor coupled to the second power supply unit to charge the bulk capacitance to the predetermined level. ### Claim 12 (depends on 11) The device of claim 11, wherein the control circuit reverse-biases the ORing transistor such that power from the second power supply unit charges the bulk capacitance. ### Claim 13 (depends on 9) The device of claim 9, wherein the control unit disconnects the first power supply unit using a switch. ### Claim 14 (depends on 9) The device of claim 9, wherein the control unit: receives an enable signal that indicates the first power supply unit should be connected to the at least one electronic component; and connects, in response to the received enable signal, the first power supply unit such that the first power supply unit supplies power to the at least one electric component. ### Claim 15 (depends on 9) The device of claim 9, wherein the predetermined level comprises a voltage level. ### Claim 16 A networking device comprising: means for receiving a source power supply; a first means for outputting a regulated supply power derived from the source power supply to at least one electronic component over a power distribution bus; a second means for outputting a regulated supply power to the at least one electronic component over the power distribution bus in parallel with the first means; means for receiving a disable signal that indicates the regulated supply power corresponding to the first means should be not be output such that the at least one electronic component does not receive the regulated supply power; means for not outputting, in response to the disable signal, the regulated supply power corresponding to the first means; and means for charging, in response to the disable signal and by delivering the regulated supply power from the second means to a bulk capacitance of the first means to a predetermined level while not outputting the regulated supply power from the first means to the at least one electronic component, wherein the bulk capacitance is associated with the first means for outputting the regulated supply power. ### Claim 17 (depends on 1) The method of claim 1, wherein charging, in response to the disable signal, the bulk capacitance of the first power supply unit to the predetermined level reduces a turn-on time of the first power supply unit. ### Claim 18 (depends on 9) The device of claim 9, wherein the control unit coupled to the first power supply unit is configured to reduce a turn-on time of the first power supply unit by being configured to charge, in response to the disable signal, the bulk capacitance of the first power supply unit to the predetermined level while the first power supply unit is disconnected from the source power supply.