Abstract: Power converters that produce less noise are disclosed. For example, in an embodiment, power converter can include a first inductor magnetically coupled to a second inductor, wherein a first end of the second inductor is electrically open and a second end of the second inductor is electrically coupled to ground via a second capacitor, a transistor electrically connected to the first inductor, and control circuitry to control switching of the transistor, wherein when the transistor is repeatedly switched on and off by the control circuitry, a current loop is formed through the transistor, the second capacitor, the first inductor and the second inductor, the current loop causing a reduced amount of switching noise to be generated by the power converter.

Abstract: Aspects of the disclosure provide a method. The method includes determining a power adjustment to a load, determining whether a switching frequency of a pulse width modulation (PWM) signal is within a specific range, and adjusting the switching frequency of the PWM signal based on the power adjustment to control power transfer to the load. The switching frequency is adjusted to remain in the specific range.

Abstract: Aspects of the disclosure provide a method. The method includes regulating a time for turning on a switch to transfer energy via a transformer in a first control mode, determining a turn-on time for a second control mode based on the regulated time in the first control mode, and controlling the switch based on the determined turn-on time in the second control mode to transfer energy via the transformer.

Abstract: An apparatus includes a first LED driver configured to control a first string of LEDs, a second LED driver configured to control a second string of LEDs, a third LED driver configured to control a third string of LEDs, and a control circuit configured to receive a control signal and to control the first, second, and third LED drivers so that the first, second, and third strings of LEDs cooperate in producing light according to the control signal and a color curve.

Abstract: Aspects of the disclosure provide a circuit that includes a driver circuit and a current limiter circuit. The driver circuit is configured to drive a load with an output current when the load is coupled with the driver circuit. The current limiter circuit is configured to turn on a path to deplete a portion of the output current from the driver circuit in order to prevent a load current flowing through the load from exceeding a current limit.

Abstract: Embodiments include an apparatus comprising: a magnetic component arrangement; and a switch coupled to the magnetic component arrangement, wherein the switch is configured to operate during a first time period, at a first frequency that results in transfer of a first amount of power to a lighting element via the magnetic component arrangement, and during a second time period, at a second frequency that results in transfer of a second amount of power to the lighting element via the magnetic component arrangement.

Abstract: Embodiments include circuits and methods to determine peak current for current regulation. A control signal circuit monitors a current on the primary side of a transformer based a turn on time of a switch coupled to the primary side. The control signal circuit determines whether the monitored current exceeds an over-current protection threshold, and determines a duration that the monitored current exceeds the over-current protection threshold. The control signal circuit determines a peak primary current in the primary side based on the over-current protection threshold, the duration that the monitored current exceeds the over-current protection threshold, and the turn on time of the switch. The control signal circuit controls the turn on time for the switch based on the determined peak primary current.

Abstract: Power lighting control methods and systems for solid state lighting are disclosed. For example, a power control system includes a transformer that includes a primary coil configured to receive a first voltage based on an output of a switching circuit, a secondary coil configured to generate a first current based on the first voltage to power a solid-state load, and a bleeder coil coupled to a bleeder switch, and a control module that causes the bleeder switch to turn on incrementally during a dimming event over M power cycles, where M is a positive integer, so as to eliminate or reduce a current step in the first current provided to the solid state load.

Abstract: Aspects of the disclosure provide a method. The method includes detecting a dimming characteristic in an energy source that provides energy to be transferred to a load via a magnetic component, receiving a dimming control signal, and controlling a switch in connection with the magnetic component based on the dimming characteristic and the dimming control signal to transfer energy to the load via the magnetic component.

Abstract: In various embodiments, there is provided a method comprising receiving a waveform; rectifying the waveform to generate a rectified waveform; comparing the rectified waveform with a first voltage to generate a first compare signal, wherein a first edge of the first compare signal occurs at a first time when an instantaneous value of the rectified waveform becomes higher than the first voltage; comparing the rectified waveform with a second voltage to generate a second compare signal, wherein a first edge of the second compare signal occurs at a second time when the instantaneous value of the rectified waveform becomes higher than the second voltage; and based at least in part on the first time and the second time, estimating a voltage of the waveform.

Abstract: A system includes a first light emitting diode configured to produce light of a first color and a second light emitting diode configured to produce light of a second color. A constant current circuit is configured to provide a first current, wherein (i) the first current is approximately constant, (ii) a first portion of the first current flows through the second light emitting diode, and (iii) a remaining portion of the first current flows through the first light emitting diode. A current regulating circuit is configured to control the first portion of the first current flowing through the second light emitting diode. The current regulating circuit is connected in series with the second light emitting diode, the constant current circuit, and a reference potential. The first light emitting diode is connected in series directly between the constant current circuit and the reference potential.

Abstract: A controller, which may be a controller for solid-state lighting, includes a transformer, and a control circuit having a bias voltage input. The control circuit activates when voltage applied to the bias voltage input reaches a threshold. The transformer has a feedback output to the bias voltage input. The controller also has a bias voltage circuit including a resonant circuit providing a resonant current, and a bias capacitor charged by the resonant current, applying start-up bias voltage to the bias voltage input. The controller further has a cutoff to shut down the resonant current when the transformer feedback output is above the threshold. A method of operating the a controller includes providing a resonant current to charge a start-up bias capacitor. The method also includes automatically cutting off the resonant current when the transformer feedback output is above the threshold. This may be determined by monitoring the bias voltage input.

Abstract: A system including first and second lamps, one of an inductor or a transformer, first and second switches, and a control module. The first lamp generates a first output of light having a first color. The second lamp generates a second output of light having a second color. The first and second outputs of light are mixed to provide a mixture of light having a third color. The transformer includes first and second coils. The first and second coils supply power respectively to the first and second lamps. The first and second switches are connected respectively to the first and second coils. The control module alters the third color by controlling (i) a state of the first switch to adjust a first amount of current supplied to the first lamp, and (ii) a state of the second switch to adjust a second amount of current supplied to the second lamp.

Abstract: A controller for a buck regulator for a lighting system including light emitting diodes includes a voltage control loop configured to compare a voltage reference and a feedback voltage. The feedback voltage is based upon a DC supply voltage to the controller. A voltage regulator is configured to receive an output of the voltage control loop and to generate a current reference. A current control loop is configured to receive a feedback current and to compare the current reference to the feedback current. A current regulator is configured to receive an output of the current control loop. A pulse width modulation circuit is configured to receive an output of the current regulator and to generate drive signals for first and second switches of the buck regulator.

Abstract: An apparatus includes an input node, a light-emitting diode (LED) string to receive a current from the input node, a voltage divider to output a control voltage, and a switch to receive the control voltage. The switch coupled to the LED string controls the current through the LED string according to the control voltage.

Abstract: An integrated circuit including a die of the integrated circuit, the die including an insulating layer, light emitting diodes, a semiconductor layer, and a control module. The insulating layer includes a first side and a second side. The second side is opposite to the first side. The light emitting diodes are arranged on the first side of the insulating layer. The semiconductor layer is arranged adjacent to the second side of the insulating layer. The light emitting diodes are connected to the semiconductor layer using connections from the first side of the insulating layer to the second side of the insulating layer. The control module is arranged on the semiconductor layer. The control module is configured to output pulse width modulated pulses to the light emitting diodes via the connections.

Abstract: A system configured to provide current to power a solid-state light emitting diode in accordance with a dimming level, wherein the dimming level corresponds to an amount of light provided from the solid-state light emitting diode. The system includes a transformer and a switch. The transformer includes a coil. The transformer is configured to receive a first current. The coil is configured to, based on the first current, output a second current to power the solid-state light emitting diode. The switch is configured to, based on a dimming level that corresponds to the amount of light provided from the solid-state light emitting diode of the system, bleed a portion of the second current out of the coil to a ground reference in order to divert the portion of the second current from being supplied to the solid-state light emitting diode.

Abstract: Aspects of the disclosure provide a method that including receiving a sensed signal corresponding to a current flowing through an energy transfer module in response to an on/off state of a forward-type triode for alternating current (TRIAC), determining the TRIAC on/off state based on the sensed signal, and controlling the energy transfer module based on the determined TRIAC on/off state.

Abstract: Embodiments include circuits and methods to determine peak current for current regulation. A control signal circuit monitors a current on the primary side of a transformer based a turn on time of a switch coupled to the primary side. The control signal circuit determines whether the monitored current exceeds an over-current protection threshold, and determines a duration that the monitored current exceeds the over-current protection threshold. The control signal circuit determines a peak primary current in the primary side based on the over-current protection threshold, the duration that the monitored current exceeds the over-current protection threshold, and the turn on time of the switch. The control signal circuit controls the turn on time for the switch based on the determined peak primary current.

Abstract: A system including a selection module to select one of a plurality of templates corresponding to a plurality of light emitting diodes, where the selected template includes one or more of temperature, current, and voltage characteristics of the plurality of light emitting diodes. A control module measures a voltage across one of the plurality of light emitting diodes; determines a temperature of the plurality of light emitting diodes based on the voltage measured across the one of the plurality of light emitting diodes and the selected template; and in order to maintain a luminosity of the plurality of light emitting diodes at a predetermined luminosity, adjusts current through the plurality of light emitting diodes based on the temperature, the selected template, and calibration data. The calibration data include current through the plurality of light emitting diodes and corresponding luminosities of the plurality of light emitting diodes.