# US 12,009,825 B2 · Switch control systems for light emitting diodes and methods thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,009,825 B2 - Document ID: US12009825B2 - Status: Granted - Kind: B2 - Application number: 17/502,916 - Filed: 2021-10-15 - Published: 2022-05-12 - Granted: 2024-06-11 - Earliest claimed: 2017-07-10 - Assignees: On-Bright Electronics (Shanghai) Co., Ltd. - Applicants: On-Bright Electronics (Shanghai) Co., Ltd. - Inventors: Liqiang Zhu; Jun Zhou - Web page: https://patentgrep.com/patent/US12009825B2 ## CPC - H03K 5/24: the characteristic being amplitude - H05B 45/10: Controlling the intensity of the light - H05B 45/3575: by means of dummy loads or bleeder circuits, e.g. for dimmers - H05B 45/395: Linear regulators - H05B 47/20: Responsive to malfunctions or to light source life; for protection - G01R 19/16538: {in AC or DC supplies (G01R19/16519 and G01R19/16528 take precedence)} - Y02B 20/30: Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED] - Y02B 20/40: Control techniques providing energy savings, e.g. smart controller or presence detection - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract System and method for controlling one or more light emitting diodes. For example, the system for controlling one or more light emitting diodes includes a current generator configured to generate a first current flowing through one or more light emitting diodes. The one or more light emitting diodes are configured to receive a rectified voltage generated by a rectifying bridge coupled to a TRIAC dimmer. Additionally, the system includes a bleeder configured to receive the rectified voltage, and a controller configured to receive a sensing voltage from the current generator and output a control signal to the bleeder. The sensing voltage indicates a magnitude of the first current. ## Claims ### Claim 1 A system for controlling one or more light emitting diodes, the system comprising: a current generator configured to generate a first current flowing through the one or more light emitting diodes, the one or more light emitting diodes being configured to receive a rectified voltage generated by a rectifying bridge coupled to a TRIAC dimmer; a bleeder configured to receive the rectified voltage; and a controller configured to: receive a sensing voltage from the current generator, the sensing voltage indicating a magnitude of the first current; receive an input voltage generated by a voltage divider, the voltage divider being configured to receive the rectified voltage, the input voltage indicating a magnitude of the rectified voltage; and output a control signal to the bleeder; wherein the controller is further configured to: generate the control signal to turn off the bleeder if the input voltage satisfies a first condition so that the bleeder does not generate a second current, the second current being larger than zero in magnitude; and generate the control signal to turn on the bleeder if the input voltage satisfies a second condition so that the bleeder generates the second current; wherein the second condition is different from the first condition; wherein: the controller includes a flip-flop; and the flip-flop is configured to directly output the control signal. ### Claim 2 (depends on 1) The system of claim 1 wherein the controller is further configured to: generate the control signal at a first logic level from a first time to a second time, during which the input voltage is smaller than a reference voltage in magnitude; generate the control signal at a second logic level from the second time to a third time, during which the input voltage is larger than the reference voltage in magnitude; and generate the control signal at the first logic level from the third time to a fourth time, during which the input voltage is smaller than the reference voltage in magnitude; wherein the first logic level and the second logic level are different. ### Claim 3 (depends on 2) The system of claim 2 wherein: the control signal at the first logic level is configured to turn on the bleeder so that the bleeder generates the second current; and the control signal at the second logic level is configured to turn off the bleeder so that the bleeder does not generate the second current. ### Claim 4 (depends on 1) The system of claim 1 wherein the rectifying bridge is coupled to the TRIAC dimmer through a fuse. ### Claim 5 (depends on 1) The system of claim 1 wherein: the controller further includes a comparator; the comparator is configured to generate a comparison signal based on the sensing voltage; and the flip-flop is further configured to receive the comparison signal and generate the control signal based at least in part on the comparison signal. ### Claim 6 A method for controlling one or more light emitting diodes, the method comprising: generating a first current flowing through the one or more light emitting diodes, the one or more light emitting diodes being configured to receive a rectified voltage generated by a rectifying bridge coupled to a TRIAC dimmer; receiving a sensing voltage, the sensing voltage indicating a magnitude of the first current; receiving an input voltage, the input voltage indicating a magnitude of the rectified voltage; and outputting, by a controller, a control signal to the bleeder; wherein the outputting a control signal to the bleeder includes: generating the control signal, by a flip-flop in the controller, to turn off the bleeder if the input voltage satisfies a first condition so that the bleeder does not generate a second current, the second current being larger than zero in magnitude; generating, by the flip-flop in the controller, the control signal to turn on the bleeder if the input voltage satisfies a second condition so that the bleeder generates the second current; and directly outputting, b the flip-flop in the controller, the control signal; wherein the second condition is different from the first condition. ### Claim 7 A system for controlling one or more light emitting diodes, the system comprising: a current generator configured to generate a first current flowing through the one or more light emitting diodes, the one or more light emitting diodes being configured to receive a rectified voltage generated by a rectifying bridge coupled to a TRIAC dimmer; a bleeder configured to receive the rectified voltage; and a controller configured to: receive a sensing voltage from the current generator, the sensing voltage indicating a magnitude of the first current; receive an input voltage generated by a voltage divider, the voltage divider being configured to receive the rectified voltage, the input voltage indicating a magnitude of the rectified voltage; and output a control signal to the bleeder; wherein the controller is further configured to: generate the control signal at a first logic level from a first tune to a second time, during which the input voltage is smaller than a reference voltage in magnitude; generate the control signal at a second logic level from the second time to a third tune, during which the input voltage is larger than the reference voltage in magnitude; and generate the control signal at the first logic level from the third time to a fourth time, during which the input voltage is smaller than the reference voltage in magnitude; wherein the first logic level and the second logic level are different; wherein: the controller includes a flip-flop; and the flip-flop is configured to directly output the control signal. ### Claim 8 (depends on 7) The system of claim 7 wherein: the control signal at the first logic level is configured to turn on the bleeder so that the bleeder generates a second current; and the control signal at the second logic level is configured to turn off the bleeder so that the bleeder does not generate the second current. ### Claim 9 (depends on 7) The system of claim 7 wherein the rectifying bridge is coupled to the TRIAC dimmer through a fuse. ### Claim 10 A method for controlling one or more light emitting diodes, the method comprising: generating a first current flowing through the one or more light emitting diodes, the one or more light emitting diodes being configured to receive a rectified voltage generated by a rectifying bridge coupled to a TRIAC dimmer; receiving a sensing voltage, the sensing voltage indicating a magnitude of the first current; receiving an input voltage, the input voltage indicating a magnitude of the rectified voltage; and outputting, by a controller, a control signal to the bleeder; wherein the outputting a control signal to the bleeder includes: generating, by a flip-flop in the controller, the control signal at a first logic level from a first time to a second time, during which the input voltage is smaller than a reference voltage in magnitude; generating, by the flip-flop in the controller, the control signal at a second logic level from the second time to a third time, during which the input voltage is larger than the reference voltage in magnitude; generating, by the flip-flop in the controller, the control signal at the first logic level from the third time to a fourth time, during which the input voltage is smaller than the reference voltage in magnitude; and directly outputting, b the flip-flop in the controller, the control signal; wherein the first logic level and the second logic level are different. ### Claim 11 (depends on 7) The system of claim 7 wherein: the controller further includes a comparator; the comparator is configured to generate a comparison signal based on the sensing voltage; and the flip-flop is further configured to receive the comparison signal and generate the control signal based at least in part on the comparison signal.