# US 2018/0026534 A1 · Controlled Adaptive Power Limiter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0026534 A1 - Document ID: US20180026534A1 - Status: Published application - Kind: A1 - Application number: 15/651,713 - Filed: 2017-07-17 - Published: 2018-01-25 - Earliest claimed: 2016-07-19 - Assignees: Microchip Technology Incorporated - Applicants: Microchip Technology Incorporated - Inventors: Gheorghe Turcan - Web page: https://patentgrep.com/patent/US20180026534A1 ## CPC - H02M 3/156: with automatic control of output voltage or current, e.g. switching regulators - H02M 1/08: Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters - H02M 1/32: Means for protecting converters other than automatic disconnection - H02M 1/0009: {Devices or circuits for detecting current in a converter} - H02M 3/33507: {with automatic control of the output voltage or current, e.g. flyback converters (H02M3/33561, H02M3/33569 take precedence)} - 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 limiter for a switched mode power supply includes an operational amplifier and a comparator circuit. The operational amplifier is configured to receive an input voltage supplied to the SMPS as a first input and a reference voltage as a second input. The comparator circuit is configured to receive an output of the operational amplifier, receive a current sense signal, and generate an output signal configured to control a power generator. The output signal is based on a comparison between the output of the operational amplifier and the current sense signal. ## Claims ### Claim 1 A power limiter for a switched mode power supply (SMPS), comprising: an operational amplifier configured to: receive an input voltage supplied to the SMPS as a first input; and a reference voltage as a second input; a comparator circuit configured to: receive an output of the operational amplifier; receive a current sense signal; and generate an output signal configured to control a power generator, the output signal based on a comparison between the output of the operational amplifier and the current sense signal. ### Claim 2 (depends on 1) The power limiter of claim 1, wherein the output of the operational amplifier is a current limit. ### Claim 3 (depends on 1) The power limiter of claim 1, wherein the comparator circuit is further configured to generate the output signal based on a comparison between a set current limit and a measured current by comparing the output of the operational amplifier and the current sense signal. ### Claim 4 (depends on 1) The power limiter of claim 1, wherein the output signal is configured to overwrite a feedback signal from output of the SMPS. ### Claim 5 (depends on 1) The power limiter of claim 1, wherein: the output signal is configured to overwrite a feedback signal from output of the SMPS; and the comparator circuit is further configured to generate the output signal before reception of the feedback signal. ### Claim 6 (depends on 1) The power limiter of claim 1, wherein the operational amplifier and the comparator unit are incorporated into a microcontroller. ### Claim 7 (depends on 1) The power limiter of claim 1, wherein the operational amplifier is further configured to lower a current input limit as input voltage increases. ### Claim 8 (depends on 1) The power limiter of claim 1, wherein the operational amplifier is further configured to lower a current input limit as input voltage increases according to a slope defined by one or more resistors connected between an input voltage source and the operational amplifier. ### Claim 9 (depends on 1) The power limiter of claim 1, wherein the operational amplifier is further configured to maintain a current limit above zero based upon the reference voltage. ### Claim 10 A switched mode power supply (SMPS), comprising: an operational amplifier configured to: receive an input voltage supplied to the SMPS as a first input; and a reference voltage as a second input; a pulse-width modulation power generator circuit configured to produce an output voltage based on a duty cycle of a pulse-width modulation output; and a comparator circuit configured to: receive an output of the operational amplifier; receive a current sense signal based on output of the pulse-width modulation power generator circuit; and generate an output signal configured to control the power generator, the output signal based on a comparison between the output of the operational amplifier and the current sense signal. ### Claim 11 (depends on 10) The SMPS of claim 10, wherein the output of the operational amplifier is a current limit. ### Claim 12 (depends on 10) The SMPS of claim 10, wherein the comparator circuit is further configured to generate the output signal based on a comparison between a set current limit and a measured current by comparing the output of the operational amplifier and the current sense signal. ### Claim 13 (depends on 10) The SMPS of claim 10, wherein the output signal is configured to overwrite a feedback signal from output of the SMPS. ### Claim 14 (depends on 10) The SMPS of claim 10, wherein: the output signal is configured to overwrite a feedback signal from output of the SMPS; and the comparator circuit is further configured to generate the output signal before reception of the feedback signal. ### Claim 15 (depends on 10) The SMPS of claim 10, wherein the operational amplifier and the comparator unit are incorporated into a microcontroller. ### Claim 16 (depends on 10) The SMPS of claim 10, wherein the operational amplifier is further configured to lower a current input limit as input voltage increases. ### Claim 17 (depends on 10) The SMPS of claim 10, wherein the operational amplifier is further configured to lower a current input limit as input voltage increases according to a slope defined by one or more resistors connected between an input voltage source and the operational amplifier. ### Claim 18 (depends on 10) The SMPS of claim 10, wherein the operational amplifier is further configured to maintain a current limit above zero based upon the reference voltage. ### Claim 19 A microcontroller, comprising: an operational amplifier configured to: receive an input voltage supplied to the SMPS as a first input; and a reference voltage as a second input; and a comparator circuit configured to: receive an output of the operational amplifier; receive a current sense signal; and generate an output signal configured to control a power generator, the output signal based on a comparison between the output of the operational amplifier and the current sense signal. ### Claim 20 (depends on 1) The microcontroller of claim 1, wherein the output of the operational amplifier is a current limit.