Abstract: Methods and apparatus for driving discharge lamps are disclosed herein. In one embodiment, a method for driving a discharge lamp includes generating a switching signal to drive a discharge lamp, monitoring a working status of the discharge lamp, and determining whether the discharge lamp is operating abnormally based at least in part on the monitored working status. The method also includes decreasing a duty cycle of the switching signal when the discharge lamp is determined to operate abnormally.

Abstract: Various embodiments of LED drivers and associated methods of are described below. In one embodiment, a method for controlling an LED driver includes receiving a reference voltage, receiving a feedback voltage from said LED driver, receiving said input voltage as a first feed forward voltage and said output voltage as a second feed forward voltage, generating a hysteretic width based on said first feed forward voltage and said second feed forward voltage, and generating a hysteretic band voltage using said hysteretic width and said reference voltage. The method also includes generating a first control signal for controlling said LED driver based on said hysteretic band voltage and said feedback voltage, inverting said first control signal to generate a second control signal for controlling said LED driver, and achieving a generally fixed frequency for said LED driver.

Abstract: The present disclosure discloses a multi-mode dimming circuit configurable to operate in a first dimming mode, a second dimming mode and a third dimming mode. The present disclosure also discloses separate dimming circuits for respectively realize the three dimming modes. In one embodiment the multi-mode dimming circuit may comprise a first input terminal, a second input terminal, a third input terminal, an output terminal, a resistive device, an oscillation circuit and a pulse width modulation (PWM) circuit. Users may flexibly configure the multi-mode dimming circuit to operate in one of the three different dimming modes by varying the external devices and/or signals coupled to each of the first, second and third input terminals.

Abstract: A current balance scheme for driving LED strings is disclosed. A power supply unit provides a driving voltage to drive a plurality of LED strings. A feedback selector is configured to select a minimum feedback signal indicative of the driving voltage to the power supply unit for regulating the driving voltage. Based on the minimum feedback signal, the driving voltage gets a minimum value to sufficiently drive the plurality of LED strings. A protection circuit is configured to protect the current balance circuit from high voltage especially when there is a shorted LED string.

Abstract: The present disclosure discloses a light emitting element driving circuit. In one embodiment the light emitting element driving circuit may comprise a power conversion circuit and a current balancing circuit. In other embodiment the light emitting element driving circuit may further comprise other modules integrated and interacting with the power conversion circuit and the current balancing circuit, such as fault detection and protection circuits, status indication circuits and phase-shift PWM dimming circuits. In other embodiment, the present disclosure further discloses a current balancing circuit. In other embodiment, the present disclosure further discloses a fault detection and protection circuit. In still other embodiment, the present disclosure further discloses a phase-shift PWM dimming circuit.

Abstract: The present invention provides a method and apparatus for driving multiple parallel discharge lamps, which increases the switching frequency once the open lamp condition is detected to provide an output voltage that is high enough to ignite the lamp again.

Abstract: Triac dimmer compatible switching mode power supplies used as LED drivers are disclosed herein. A PFC controller is configured in the switching mode power supplies. With the PFC controller, the current keeping the triac in the on-state is supplied by the DC/DC converter, and the LC resonance is reduced.

Abstract: Circuitry and methods for driving a plurality of LED strings are disclosed herein. In one embodiment, the circuitry comprises a plurality of current regulating circuits electrically coupled to the LED strings and are configured to regulate a current flowing through the LED strings. At least two control circuits are coupled to the current regulating circuits and are configured to generate a control signal according to terminal voltages of the corresponding current regulating circuits. A voltage converter is electrically coupled to the LED strings and to the at least two control circuits, and is configured to regulate the DC driving voltage according to the at least two control signals.

Abstract: The present technology are directed to switching mode power supplies with primary side control. In one embodiment, the switching mode power supply provides an equivalent current signal which represents a load current. The equivalent current signal is then used to control a switching circuit in the switching mode power supply.

Abstract: Methods and circuits for CCFL driving circuit control are disclosed according to various embodiments of the present disclosure. In certain embodiments, the methods and circuits for CCFL driving circuit control provide a control signal for regulating both the duty ratio and frequency of the switching control signal that controls the CCFL driving circuit. External components for control loop compensation and frequency sweeping rate, and/or striking frequency setting may also be utilized.

Abstract: Methods and apparatus for driving discharge lamps are disclosed herein. In one embodiment, a method for driving a discharge lamp includes generating a switching signal to drive a discharge lamp, monitoring a working status of the discharge lamp, and determining whether the discharge lamp is operating abnormally based at least in part on the monitored working status. The method also includes decreasing a duty cycle of the switching signal when the discharge lamp is determined to operate abnormally.

Abstract: The present invention provides a method and apparatus for driving multiple parallel discharge lamps, which increases the switching frequency once the open lamp condition is detected to provide an output voltage that is high enough to ignite the lamp again.