# US 9,438,119 B1 · Switching power supply having loading condition remembrance and improved hold-up time characteristics > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,438,119 B1 - Document ID: US9438119B1 - Status: Granted - Kind: B1 - Application number: 12/549,222 - Filed: 2009-08-27 - Granted: 2016-09-06 - Earliest claimed: 2009-08-27 - Assignees: Champion Microelectronic Corp. - Applicants: Jeffrey Hwang - Inventors: Jeffrey Hwang - Web page: https://patentgrep.com/patent/US9438119B1 ## CPC - H02M 1/4225: {using a non-isolated boost converter} - H02M 3/335: using semiconductor devices only - H02M 3/33592: {having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer} - H02M 1/007: {Plural converter units in cascade (push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826)} - H02M 1/0096: {Means for increasing hold-up time, i.e. the duration of time that a converter's output will remain within regulated limits following a loss of input power} - Y02B 70/10: Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes - Y02P 80/10: Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier - 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) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract A switching power supply comprises one or more power supply stages that receive power from an input power source and that generate a regulated output voltage for powering a load by alternately opening and closing a set of switches. Controller circuitry monitors the input power source for loss of power as well as a state of the load. When loss of power is detected, the controller circuitry saves a state of the load. ## Claims ### Claim 1 A switching power supply comprising: one or more power supply stages that receive power from an input power source and that generate a regulated output voltage for powering a load by alternately opening and closing a set of switches; and controller circuitry that monitors the input power source for loss of power and that monitors a state of the load, and when loss of power is detected, the controller circuitry saves a state of the load, wherein the state of the load represents a level of power drawn by the load. ### Claim 2 (depends on 1) The switching power supply according to claim 1, wherein said alternately opening and closing a set of switches is disabled in response said loss of power being detected. ### Claim 3 (depends on 2) The switching power supply according to claim 2, wherein the controller circuitry uses the saved state of the load for generating a signal that disables said alternately opening and closing a set of switches. ### Claim 4 (depends on 3) The switching power supply according to claim 3, wherein said alternately opening and closing a set of switches is disabled under different conditions, which conditions depend upon the state of the load at the time the line voltage was lost. ### Claim 5 (depends on 1) The switching power supply according to claim 1, wherein said alternately opening and closing the set of switches is disabled a period of time after the line voltage is lost wherein the period of time is different depending upon the state of the load at the time the line voltage was lost. ### Claim 6 (depends on 5) The switching power supply according to claim 5, wherein the state of the load is heavy or light. ### Claim 7 (depends on 1) The switching power supply according to claim 1, wherein the one or more power supply stages include a first power supply stage that receives a line voltage from an input power source and that generates an intermediate voltage; and a second power supply stage that receives the intermediate voltage and generates the regulated output voltage. ### Claim 8 (depends on 7) The switching power supply according to claim 7, wherein the first power supply stage performs power factor correction. ### Claim 9 (depends on 7) The switching power supply according to claim 7, wherein the intermediate voltage is regulated at a first voltage level when the state of the load is heavy and at a second voltage level, lower than the first, when the state of the load is light. ### Claim 10 (depends on 7) The switching power supply according to claim 7, wherein the state of the load is determined by comparing an error voltage to a predetermined threshold. ### Claim 11 (depends on 10) The switching power supply according to claim 10, wherein the error voltage is representative of a difference between the level of the intermediate voltage and a desired level for the intermediate voltage. ### Claim 12 (depends on 11) The switching power supply according to claim 11, wherein a comparator performs said comparing using hysteresis. ### Claim 13 (depends on 1) The switching power supply according to claim 1, wherein the input power source is monitored for loss of power by monitoring a level of an input current received from the input power source by the one or more power supply stages. ### Claim 14 (depends on 13) The switching power supply according to claim 13, wherein the loss of power is detected when the level of the input current falls below a predetermined threshold. ### Claim 15 A method of operating a switching power supply comprising: receiving power from an input power source and generating a regulated output voltage for powering a load by alternately opening and closing a set of switches; monitoring the input power source for loss of power; monitoring a state of the load; and saving the state of the load upon detection of loss of power by said monitoring the input power source, wherein the state of the load represents a level of power drawn by the load. ### Claim 16 (depends on 15) The method of operating a switching power supply according to claim 15, wherein said alternately opening and closing a set of switches is disabled in response said loss of power being detected. ### Claim 17 (depends on 16) The method of operating a switching power supply according to claim 16, further comprising using the saved state of the load for generating a signal that disables said alternately opening and closing a set of switches. ### Claim 18 (depends on 17) The method of operating a switching power supply according to claim 17, wherein said alternately opening and closing a set of switches is disabled under different conditions, which conditions depend upon the state of the load at the time the line voltage was lost. ### Claim 19 (depends on 15) The method of operating a switching power supply according to claim 15, wherein said alternately opening and closing the set of switches is disabled a period of time after the line voltage is lost wherein the period of time is different depending upon the state of the load at the time the line voltage was lost. ### Claim 20 (depends on 15) The method of operating a switching power supply according to claim 15, wherein the one or more power supply stages include a first power supply stage that receives a line voltage from an input power source and that generates an intermediate voltage; and a second power supply stage that receives the intermediate voltage and generates the regulated output voltage. ### Claim 21 (depends on 20) The method of operating a switching power supply according to claim 20, wherein the intermediate voltage is regulated at a first voltage level when the state of the load is heavy and at a second voltage level, lower than the first, when the state of the load is light. ### Claim 22 A switching power supply comprising: one or more power supply stages that receive power from an input power source and that generate a regulated output voltage for powering a load by alternately opening and closing a set of switches; and controller circuitry that monitors the input power source for loss of power and that monitors a level of power drawn by the load, and when loss of power is detected, the controller circuitry disables said alternately opening and closing the set of switches a period of time after the line voltage is lost wherein the period of time is different depending upon the state of the load at the time the line voltage was lost. ### Claim 23 (depends on 22) The switching power supply according to claim 22, wherein the one or more power supply stages include a first power supply stage that receives a line voltage from an input power source and that performs power factor correction to generate an intermediate voltage and a second power supply stage that receives the intermediate voltage and generates the regulated output voltage. ### Claim 24 (depends on 23) The switching power supply according to claim 23, wherein the intermediate voltage is regulated at a first voltage level when the state of the load is heavy and at a second voltage level, lower than the first, when the state of the load is light. ### Claim 25 (depends on 24) The switching power supply according to claim 24, wherein the state of the load is determined by comparing an error voltage to a predetermined threshold. ### Claim 26 (depends on 25) The switching power supply according to claim 25, wherein the error voltage is representative of a difference between the level of the intermediate voltage and a desired level for the intermediate voltage. ### Claim 27 (depends on 26) The switching power supply according to claim 26, wherein a comparator performs said comparing using hysteresis.