# US 10,122,179 B2 · Power supplies with feedback > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,122,179 B2 - Document ID: US10122179B2 - Status: Granted - Kind: B2 - Application number: 15/192,840 - Filed: 2016-06-24 - Published: 2017-11-23 - Granted: 2018-11-06 - Earliest claimed: 2016-05-19 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Todd Sutton; Charles Tuten - Web page: https://patentgrep.com/patent/US10122179B2 ## CPC - H02J 4/00: Circuit arrangements for mains or distribution networks not specified as AC or DC; Circuit arrangements for mains or distribution networks combining AC and DC sections or sub-networks (arrangements using intermediate DC-AC-DC conversion H02J1/002; arrangements using high-voltage DC [HVDC] links H02J3/36) - G06F 1/26: Power supply means, e.g. regulation thereof (for memories G11C) - H02M 3/1584: {with a plurality of power processing stages connected in parallel} - H02M 3/1566: {with means for compensating against rapid load changes, e.g. with auxiliary current source, with dual mode control or with inductance variation} - Y02P 80/14: District level solutions, i.e. local energy networks - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - 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) - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract Features and advantages of certain embodiments include a plurality of power supplies that work together to deliver power to a target circuit. In one embodiment, a downstream power supply provides a fast current delivery in response to load current transients and generates a feedback signal to control an upstream power supply so that the upstream and downstream power supplies work together to meet the current and voltage requirements of a target circuit across a wide range of loading conditions. ## Claims ### Claim 1 A circuit comprising: a second power supply coupled to a second power supply rail, the second power supply configured to provide a second current to the second power supply rail in response to a loading event on the second power supply rail and generate a feedback signal indicating the loading event; a first power supply coupled to the second power supply to receive the feedback signal and configured to produce a first current and a first voltage to a first power supply rail in response to the feedback signal; and a downstream circuit coupled to the first power supply rail, the circuit configured to receive the first current and the first voltage from the first power supply and produce a second voltage on the second power supply rail based on the received first current and first voltage, wherein the second current provided by the second power supply is transitory while the first current is provided through the circuit to respond to the loading event. ### Claim 2 (depends on 1) The circuit of claim 1 wherein the second power supply responds to the loading event faster than the first power supply. ### Claim 3 (depends on 1) The circuit of claim 1 wherein the first power supply is further configured to receive a second feedback signal based on the first voltage produced to the first power supply rail. ### Claim 4 (depends on 3) The circuit of claim 3 wherein the feedback signal modifies the second feedback signal to increase the first current from the first power supply when a third voltage on the second power supply rail drops below a nominal value. ### Claim 5 (depends on 3) The circuit of claim 3 further comprising at least one capacitor having a first terminal configured to receive the feedback signal and a second terminal coupled to a feedback input of the first power supply and to the first power supply rail. ### Claim 6 (depends on 3) The circuit of claim 3 wherein the feedback signal causes the first power supply to increase the first voltage produced to the first power supply rail for a predetermined time period. ### Claim 7 (depends on 3) The circuit of claim 3 wherein the first power supply is a switching regulator comprising a high side switching transistor, and wherein the feedback signal turns on the high side switching transistor to couple a power supply input voltage to the first power supply rail for a predetermined time period. ### Claim 8 (depends on 7) The circuit of claim 7 wherein the first power supply comprises a Buck switching regulator, and wherein the feedback signal increases an ON time of the high side switching transistor during one or more duty cycles of the Buck switching regulator. ### Claim 9 (depends on 1) The circuit of claim 1 wherein the downstream circuit comprises parasitic capacitance and parasitic inductance. ### Claim 10 (depends on 1) The circuit of claim 1 further comprising a clock sensor to sense the loading event. ### Claim 11 (depends on 1) The circuit of claim 1 further comprising a voltage sensor to sense the loading event. ### Claim 12 (depends on 1) The circuit of claim 1 further comprising a current sensor to sense the loading event. ### Claim 13 (depends on 1) The circuit of claim 1 wherein the second current is provided to a processor via the second power supply rail. ### Claim 14 (depends on 1) The circuit of claim 1 wherein the second power supply comprises: an amplifier having an input coupled to a reference voltage and an output coupled to the second power supply rail; and a current sensor configured to sense current from the output of the amplifier to the second power supply rail, and generate the feedback signal based on the sensed current. ### Claim 15 (depends on 14) The circuit of claim 14 wherein the current sensor comprises: a resistor coupled between the output of the amplifier and the second power supply rail; and a second amplifier having a first terminal coupled to a first terminal of the resistor, a second terminal coupled to a second terminal of the resistor, and an output to produce the feedback signal. ### Claim 16 (depends on 14) The circuit of claim 14 further comprising an averaging circuit having an input coupled to the current sensor to receive the feedback signal and an output coupled to a feedback input of the first power supply. ### Claim 17 (depends on 1) The circuit of claim 1 wherein the second power supply comprises: a switching regulator having an input coupled to a third power supply rail having a third voltage greater than a fourth voltage on the second power supply rail, a control input coupled to a reference voltage, and an output coupled to the second power supply rail; and a current sensor configured to sense current from the output of the switching regulator to the second power supply rail and generate the feedback signal based on the sensed current. ### Claim 18 (depends on 1) The circuit of claim 1, wherein the second power supply is located proximate to a load circuit coupled to the second power supply rail. ### Claim 19 A circuit comprising: a second power supply coupled to a second power supply rail, the second power supply configured to provide a second current to the second power supply rail in response to a loading event on the second power supply rail and generate a feedback signal indicating the loading event; a first power supply coupled to the second power supply to receive the feedback signal and configured to produce a first current and a first voltage to a first power supply rail in response to the feedback signal; and a downstream circuit coupled to the first power supply rail, the circuit configured to receive the first current and the first voltage from the first power supply and produce a second voltage on the second power supply rail based on the received first current and first voltage, wherein the second current provided by the second power supply is transitory while the first current is provided through the circuit to respond to the loading event, wherein the second power supply comprises: a first transistor having a first terminal coupled to the second power supply rail, a second terminal coupled to a third power supply rail, and a control terminal; a sense circuit to sense the loading event and generate a load event signal; and a one-shot circuit having an input coupled to receive the load event signal and an output coupled to the control terminal of the first transistor, the one-shot circuit turning on the first transistor for a predetermined time period in response to the load event signal. ### Claim 20 A method of supplying power comprising: producing a first voltage and a first current from a first power supply to a first power supply rail in response to a feedback signal, the first power supply configured to produce current and voltage in response to a loading event on a second power supply rail within a first time period; coupling the first voltage and first current through a first circuit to the second power supply rail; producing a transitory second current from a second power supply to the second power supply rail in response to the loading event within a second time period that is shorter than the first time period; and generating the feedback signal to the first power supply in response to the loading event. ### Claim 21 An apparatus, comprising: first means for producing a first voltage and a first current to a first power supply rail in response to a feedback signal, the first means configured to produce current and voltage in response to a loading event on a second power supply rail within a first time period; means for coupling the first voltage and first current to the second power supply rail; means for producing a transitory second current to the second power supply rail in response to the loading event within a second time period that is shorter than the first time period; and means for generating the feedback signal to the first means in response to the loading event.