# US 12,224,661 B2 · Systems and methods for valley locking related to quasi-resonant switching power supplies > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,224,661 B2 - Document ID: US12224661B2 - Status: Granted - Kind: B2 - Application number: 18/499,155 - Filed: 2023-10-31 - Published: 2024-05-30 - Granted: 2025-02-11 - Earliest claimed: 2020-12-28 - Assignees: On-Bright Electronics (Shanghai) Co., Ltd. - Applicants: On-Bright Electronics (Shanghai) Co., Ltd. - Inventors: Penglin Yang; Yuan Lin - Web page: https://patentgrep.com/patent/US12224661B2 ## CPC - H02M 3/01: {Resonant DC/DC converters} - H02M 1/0003: {Details of control, feedback or regulation circuits} - H02M 1/44: Circuits or arrangements for compensating for electromagnetic interference in converters or inverters - H02M 3/335: using semiconductor devices only - H02M 3/33507: {with automatic control of the output voltage or current, e.g. flyback converters (H02M3/33561, H02M3/33569 take precedence)} - H02M 1/0025: {Arrangements for modifying reference values, feedback values or error values in the control loop of a converter} - H02M 1/0035: {using burst mode control} - 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 - 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 ## Abstract Controller and method for a quasi-resonant switching power supply. For example, a controller for a quasi-resonant switching power supply includes: a valley detector configured to receive a voltage signal, detect one or more voltage valleys of the voltage signal in magnitude, and generate a detection signal representing the detected one or more voltage valleys; a valley-locking controller configured to receive one or more signals, generate a mode control signal that indicates a selected valley-locking mode based at least in part on the one or more signals, select from the detected one or more voltage valleys, one or more valleys that correspond to the selected valley-locking mode, and generate a valley control signal indicating the one or more selected valleys; and a gate driver configured to generate a drive signal based on at least information associated with the valley control signal. ## Claims ### Claim 1 A controller comprising: a valley-locking controller configured to receive one or more signals, generate a control signal that indicates a selected valley-locking mode at least in part on the one or more signals, and select, from one or more voltage valleys of a voltage signal, one or more valleys that correspond to the selected valley-locking mode, the control signal further indicating the one or more selected valleys; and a gate driver configured to generate a drive signal based on at least information associated with the control signal and change the drive signal from a first logic level to a second logic level to start multiple switching cycles in response to the one or more selected valleys; wherein, in the selected valley-locking mode, the valley-locking controller is further configured to select one or more nth valleys of the voltage signal and one or more (n+1)th valleys of the voltage signal as the one or more selected valleys, n being a positive integer; and the gate driver is further configured to: start one or more first switching cycles of the multiple switching cycles at the one or more nth valleys of the voltage signal respectively; and start one or more second switching cycles of the multiple switching cycles at the one or more (n+1)th valleys of the voltage signal respectively. ### Claim 2 (depends on 1) The controller of claim 1 wherein one first switching cycle of the one or more first switching cycles that starts at an nth valley of the voltage signal is followed immediately by one second switching cycle of the one or more second switching cycles that starts at an (n+1)th valley of the voltage signal. ### Claim 3 (depends on 2) The controller of claim 2 wherein the one second switching cycle of the one or more second switching cycles that starts at the (n+1)th valley of the voltage signal is followed immediately by another first switching cycle of the one or more first switching cycles that starts at another nth valley of the voltage signal. ### Claim 4 (depends on 3) The controller of claim 3 wherein the another first switching cycle of the one or more first switching cycles that starts at the another nth valley of the voltage signal is followed immediately by another second switching cycle of the one or more second switching cycles that starts at another (n+1)th valley of the voltage signal. ### Claim 5 (depends on 1) The controller of claim 1 wherein one second switching cycle of the one or more second switching cycles that starts at an (n+1)th valley of the voltage signal is followed immediately by one first switching cycle of the one or more first switching cycles that starts at an nth valley of the voltage signal. ### Claim 6 (depends on 5) The controller of claim 5 wherein the one first switching cycle of the one or more first switching cycles that starts at the nth valley of the voltage signal is followed immediately by another second switching cycle of the one or more second switching cycles that starts at another (n+1)th valley of the voltage signal. ### Claim 7 (depends on 6) The controller of claim 6 wherein the another second switching cycle of the one or more second switching cycles that starts at the another (n+1)th valley of the voltage signal is followed immediately by another first switching cycle of the one or more first switching cycles that starts at another nth valley of the voltage signal. ### Claim 8 (depends on 1) The controller of claim 1 wherein: the valley-locking controller is further configured to change the control signal from indicating a first valley-locking mode to indicating the selected valley-locking mode, based at least in part on the one or more signals; and in the first valley-locking mode, the gate driver is further configured to start all multiple switching cycles at multiple nth valleys of the voltage signal respectively. ### Claim 9 (depends on 8) The controller of claim 8 wherein: the valley-locking controller is further configured to change the control signal from indicating the selected valley-locking mode to indicating a second valley-locking mode, based at least in part on the one or more signals; and in the second valley-locking mode, the gate driver is further configured to start all switching cycles at multiple (n+1)th valleys of the voltage signal respectively. ### Claim 10 (depends on 1) The controller of claim 1 wherein: the valley-locking controller is further configured to change the control signal from indicating a first valley-locking mode to indicating the selected valley-locking mode, based at least in part on the one or more signals; and in the first valley-locking mode, the gate driver is further configured to start all multiple switching cycles at multiple (n+1)th valleys of the voltage signal respectively. ### Claim 11 (depends on 10) The controller of claim 10 wherein: the valley-locking controller is further configured to change the control signal from indicating the selected valley-locking mode to indicating a second valley-locking mode, based at least in part on the one or more signals; and in the second valley-locking mode, the gate driver is further configured to start all switching cycles at multiple nth valleys of the voltage signal respectively. ### Claim 12 (depends on 1) The controller of claim 1 wherein: the valley-locking controller is further configured to not to allow the control signal to change directly from indicating a first valley-locking mode to indicating a second valley-locking mode; in the first valley-locking mode, the gate driver is further configured to start all multiple switching cycles at multiple nth valleys of the voltage signal respectively; and in the second valley-locking mode, the gate driver is further configured to start all multiple switching cycles at multiple (n+1)th valleys of the voltage signal respectively. ### Claim 13 (depends on 1) The controller of claim 1 wherein: the valley-locking controller is further configured to not to allow the control signal to change directly from indicating a first valley-locking mode to indicating a second valley-locking mode; in the first valley-locking mode, the gate driver is further configured to start all multiple switching cycles at multiple (n+1)th valleys of the voltage signal respectively; and in the second valley-locking mode, the gate driver is further configured to start all multiple switching cycles at multiple nth valleys of the voltage signal respectively. ### Claim 14 (depends on 1) The controller of claim 1 wherein the voltage signal is received from a voltage divider connected to an auxiliary winding coupled to a primary winding and a secondary winding. ### Claim 15 (depends on 14) The controller of claim 14 wherein the gate driver is further configured to output the drive signal to a transistor connected to the primary winding. ### Claim 16 (depends on 15) The controller of claim 15 wherein the gate driver is further configured to change the drive signal from the first logic level to the second logic level to turn on the transistor. ### Claim 17 (depends on 16) The controller of claim 16 wherein: the first logic level is a logic low level; and the second logic level is a logic high level. ### Claim 18 (depends on 1) The controller of claim 1 wherein the one or more signals include a feedback signal representing an output voltage of a quasi-resonant switching power supply. ### Claim 19 (depends on 1) The controller of claim 1 wherein the one or more signals include the drive signal. ### Claim 20 (depends on 19) The controller of claim 19 wherein the one or more signals further include a feedback signal representing an output voltage of a quasi-resonant switching power supply. ### Claim 21 (depends on 1) The controller of claim 1 wherein the control signal represents an m-digit binary number that indicates the selected valley-locking mode. ### Claim 22 A method comprising: selecting from one or more voltage valleys of a voltage signal, one or more valleys that correspond to a selected valley-locking mode; generating a drive signal based on at least information associated with a control signal; and changing the drive signal from a first logic level to a second logic level to start multiple switching cycles in response to one or more selected valleys; wherein, in the selected valley-locking mode, the selecting from one or more voltage valleys, one or more valleys that correspond to a selected valley-locking mode includes: selecting one or more nth valleys of the voltage signal and one or more (n+1)th valleys of the voltage signal as the one or more selected valleys, n being a positive integer; and wherein, in the selected valley-locking mode, the changing the drive signal from a first logic level to a second logic level to start multiple switching cycles in response to the one or more selected valleys includes: starting one or more first switching cycles of the multiple switching cycles at the one or more nth valleys of the voltage signal respectively; and starting one or more second switching cycles of the multiple switching cycles at the one or more (n+1)th valleys of the voltage signal respectively.