# US 11,444,529 B2 · Electronic apparatus and power supply > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,444,529 B2 - Document ID: US11444529B2 - Status: Granted - Kind: B2 - Application number: 17/126,290 - Filed: 2020-12-18 - Published: 2021-06-24 - Granted: 2022-09-13 - Earliest claimed: 2019-12-18 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Duhee Jang; Kangmoon Seo; Wonmyung Woo; Sanghoon Lee; Jungho Lee - Web page: https://patentgrep.com/patent/US11444529B2 ## CPC - H02M 1/32: Means for protecting converters other than automatic disconnection - H02M 1/4225: {using a non-isolated boost converter} - H02M 1/44: Circuits or arrangements for compensating for electromagnetic interference in converters or inverters - H02M 7/06: using discharge tubes without control electrode or semiconductor devices without control electrode - H02M 7/217: using semiconductor devices only - H02M 7/219: in a bridge configuration - 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) ## Abstract A power supply capable of protecting a rectifier circuit using a switching element from an overvoltage or an overcurrent is provided. The power supply includes a power input terminal; an output capacitor; a synchronous rectifier configured to rectify an AC voltage input through the power input terminal; a converter configured to convert the rectified AC voltage into a DC voltage following a preset voltage and supply the DC voltage to the output capacitor; and a protection circuit provided between the power input terminal and the output capacitor, and configured to supply an AC voltage higher than the voltage charged in the output capacitor to the output capacitor by bypassing the synchronous rectifier. ## Claims ### Claim 1 A power supply comprising: a power input terminal; an output capacitor; a synchronous rectifier configured to rectify an AC voltage input through the power input terminal; a converter configured to convert the rectified AC voltage into a DC voltage based on a preset voltage and supply the DC voltage to the output capacitor; a protection circuit provided between the power input terminal and the output capacitor, and configured to supply an AC voltage higher than voltage charged in the output capacitor to the output capacitor by bypassing the synchronous rectifier; and an electromagnetic interference filter provided between the power input terminal and the synchronous rectifier, and configured to block high frequency noise included in the AC voltage. ### Claim 2 (depends on 1) The power supply according to claim 1, wherein the protection circuit is a diode bridge in which a pair of diodes connected in series with each other and another pair of diodes connected in series with each other are connected in parallel. ### Claim 3 (depends on 1) The power supply according to claim 1, wherein the protection circuit is further configured to bypass the synchronous rectifier and supply the AC voltage to the output capacitor until a peak voltage of the input AC voltage is the same as the voltage charged in the output capacitor. ### Claim 4 (depends on 1) The power supply according to claim 1, wherein: the synchronous rectifier comprises a plurality of switching elements; and the power supply further comprises a controller configured to control the plurality of switching elements so that the synchronous rectifier rectifies the AC voltage. ### Claim 5 (depends on 4) The power supply according to claim 4, wherein: the plurality of switching elements comprise a pair of switching elements connected in series with each other and another pair of switching elements connected in series with each other; the pair of switching elements comprises a first switching element located at an upper end and a second switching element located at a lower end; and the another pair of switching elements is configured to be connected in parallel with the pair of switching elements and comprises a third switching element located at the upper end and a fourth switching element located at the lower end. ### Claim 6 (depends on 5) The power supply according to claim 5, wherein the synchronous rectifier is further configured to be connected to the power input terminal through a connection point between the first switching element and the second switching element and a connection point between the third switching element and the fourth switching element. ### Claim 7 (depends on 5) The power supply according to claim 5, wherein the controller is further configured to control the first switching element and the fourth switching element to be turned on and off in a same phase based on a frequency of the AC voltage, and to control the second switching element and the third switching element to be turned on and off in a phase opposite to the same phase. ### Claim 8 (depends on 5) The power supply according to claim 5, wherein: the converter comprises at least one switching element; and the controller is further configured to control the at least one switching element to convert the rectified AC voltage into the DC voltage to follow the preset voltage. ### Claim 9 (depends on 1) The power supply according to claim 1, wherein the DC voltage is configured to exceed a peak value of the rectified AC voltage. ### Claim 10 A power supply comprising: a power input terminal; an output capacitor; a synchronous rectifier connected to the power input terminal, and configured to rectify an AC voltage input through the power input terminal; a converter configured to convert the rectified AC voltage into a DC voltage based on a preset voltage and supply the DC voltage to the output capacitor; a diode bridge including an input terminal connected to the power input terminal and an output terminal connected to the output capacitor; and an electromagnetic interference filter provided between the power input terminal and the synchronous rectifier, and configured to block high frequency noise included in the AC voltage. ### Claim 11 (depends on 10) The power supply according to claim 10, wherein the diode bridge is configured to bypass the synchronous rectifier and supply the AC voltage to the output capacitor until a peak voltage of the input AC voltage is the same as voltage charged in the output capacitor. ### Claim 12 (depends on 10) The power supply according to claim 10, wherein the diode bridge is further configured to bypass the synchronous rectifier and supply an AC voltage higher than voltage charged in the output capacitor to the output capacitor. ### Claim 13 (depends on 10) The power supply according to claim 10, wherein: the synchronous rectifier comprises a pair of switching elements connected in series with each other and another pair of switching elements connected in series with each other; the pair of switching elements comprises a first switching element located at an upper end and a second switching element located at a lower end; and the another pair of switching elements is configured to be connected in parallel with the pair of switching elements and comprises a third switching element located at the upper end and a fourth switching element located at the lower end. ### Claim 14 (depends on 13) The power supply according to claim 13, wherein the synchronous rectifier is further configured to be connected to the power input terminal through a connection point between the first switching element and the second switching element and a connection point between the third switching element and the fourth switching element. ### Claim 15 (depends on 10) The power supply according to claim 10, wherein the converter comprises: an inductor provided in a line connected to the synchronous rectifier; a fifth switching element provided between an inductor-side node and a ground-side node; and a diode provided in a line connecting the fifth switching element and the output capacitor. ### Claim 16 An electronic apparatus comprising: a load configured to receive power and perform an operation; and a power supply configured to supply power to the load, and comprising: a power input terminal, an output capacitor, a synchronous rectifier configured to rectify an AC voltage input through the power input terminal, a converter configured to convert the rectified AC voltage into a DC voltage based on a preset voltage and supply the DC voltage to the output capacitor, a protection circuit provided between the power input terminal and the output capacitor, and configured to supply an AC voltage higher than voltage charged in the output capacitor to the output capacitor by bypassing the synchronous rectifier, and an electromagnetic interference filter provided between the power input terminal and the synchronous rectifier, and configured to block high frequency noise included in the AC voltage.