# US 10,312,805 B2 · Current mode control DC-DC converter with single step load transient response > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,312,805 B2 - Document ID: US10312805B2 - Status: Granted - Kind: B2 - Application number: 15/075,553 - Filed: 2016-03-21 - Published: 2016-10-06 - Granted: 2019-06-04 - Earliest claimed: 2015-04-02 - Assignees: Virginia Tech Intellectual Properties, Inc. - Applicants: Virginia Tech Intellectual Properties, Inc. - Inventors: Virginia Li; Pei-Hsin Liu; Qiang Li; Fred C. Lee - Web page: https://patentgrep.com/patent/US10312805B2 ## CPC - H02M 3/156: with automatic control of output voltage or current, e.g. switching regulators - 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} - 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 converter using constant on-time (COT) or ramp pulse modulation (RPM) control achieves more rapid resumption of steady-state operation after a step-up load transient by extending an on-time of a switching pulse by interrupting a ramp voltage waveform that is compared with a threshold that equals a threshold voltage at the termination of a switching pulse or increasing a voltage with which the ramp voltage is compared. These techniques are applied to both single-phase and multi-phase power converters. ## Claims ### Claim 1 A power converter comprising a pulse generator for generating switching pulses for controlling duration of connection of said power converter to a power source based on a comparison of an output voltage of said power converter with a reference voltage, a circuit for developing a control voltage corresponding to a combination of signals representing a reference voltage, output voltage and inductor current of said power converter, a detector receiving a threshold voltage bounding said control voltage during steady-state operation of said power converter for determining when said control voltage corresponding to said combination of threshold voltage, output voltage and inductor current of said power converter represents a step-up load transient by comparison of said control voltage with said threshold voltage, and a control circuit responsive to an output of said detector for maintaining a switching pulse state from said pulse generator and connection of said power converter to said power source for a duration that said output of said detector indicates said step-up load transient. ### Claim 2 (depends on 1) The power converter as recited in claim 1, wherein said pulse generator generates pulses of constant on-time and variable duty cycle, depending on load, during steady-state operation. ### Claim 3 (depends on 1) The power converter as recited in claim 1, wherein said pulse generator terminates a pulse when a ramp voltage generated concurrently with pulses from said pulse generator equals said control voltage. ### Claim 4 (depends on 1) The power converter as recited in claim 1, wherein said power converter is a multi-phase power converter. ### Claim 5 (depends on 2) The power converter as recited in claim 2, wherein said detector detects a step-up load transient by determining when said control voltage is above a threshold that bounds said control voltage during steady-state operation. ### Claim 6 (depends on 3) The power converter as recited in claim 3, wherein said detector detects a step-up load transient by determining when said control voltage is above a threshold that bounds said control voltage during steady-state operation. ### Claim 7 (depends on 5) The power converter a recited in claim 5, wherein said detector disables termination of a pulse by said pulse generator. ### Claim 8 (depends on 5) The power converter as recited in claim 5, wherein said control circuit interrupts said ramp voltage during said step-up load transient. ### Claim 9 (depends on 5) The power converter as recited in claim 5, wherein said control voltage is increased for comparison with said ramp voltage. ### Claim 10 (depends on 5) The power converter as recited in claim 5, wherein a high voltage is substituted for said control voltage for a duration of said step-up load transient. ### Claim 11 (depends on 6) The power converter a recited in claim 6, wherein said detector disables termination of a pulse by said pulse generator. ### Claim 12 (depends on 11) The power converter as recited in claim 11, wherein said control circuit interrupts said ramp voltage during said step-up load transient. ### Claim 13 (depends on 11) The power converter as recited in claim 11, wherein said control voltage is increased for comparison with said ramp voltage. ### Claim 14 (depends on 11) The power converter as recited in claim 11, wherein a high voltage is substituted for said control voltage for a duration of said step-up load transient. ### Claim 15 A method of operating a power converter, said method comprising steps of generating pulses for controlling a switch to connect said power converter to a power source, detecting a duration of a step-up load transient in said power converter, and extending a pulse for controlling said switch for said duration of said step-up load transient wherein said extending step is performed by substituting a high voltage for a threshold voltage for comparison with a ramp voltage for a duration of said step-up load transient to terminate said pulse. ### Claim 16 (depends on 15) The method as recited in claim 15, wherein said pulses are of constant duration during steady-state operation. ### Claim 17 (depends on 15) The method as recited in claim 15 wherein said extending step is performed by amplifying a voltage that exceeds a threshold to develop a high voltage for comparison with a ramp voltage for a duration of said step-up load transient to terminate said pulse. ### Claim 18 (depends on 15) The method as recited in claim 15, wherein said power converter is a multi-phase power converter. ### Claim 19 A method of operating a power converter, said method comprising steps of generating pulses for controlling a switch to connect said power converter to a power source, detecting a duration of a step-up load transient in said power converter, and extending a pulse for controlling said switch for a said duration of said step-up load transient wherein said extending step is performed by interrupting a ramp voltage generated concurrently with said pulses during steady state operation. ### Claim 20 (depends on 17) The method as recited in claim 17, wherein said pulses are of constant duration during steady-state operation.