The present invention relates to a lighting apparatus driver, comprising: a filter, which is used to filter out noise; a rectifier, which is used to convert an alternating current voltage into a direct current voltage; and a plurality of voltage regulator integrated circuit (IC) modules, which are directly or indirectly connected to the rectifier, wherein each one of the plurality of voltage regulator IC modules is used to connect to a separate lighting apparatus, so that each one of the plurality of voltage regulator IC modules can independently control the electric current inputted into the lighting apparatus connected thereto.

A switch control circuit and a switch control method are provided. The switch control circuit includes a load, an inductor, a control switch, and a sensing resistance connected in series to an input power; an integrator that integrates a sensing voltage and a load current setting voltage to generate an integrated signal; a comparator that compares the integrated signal and a bias voltage; a switch driver that controls the control switch based on an output of the comparator and an output of an off time controller; and a gate sensor that outputs, to the integrator, a gate sensing signal that senses a time when an input of a gate terminal of the control switch becomes a low level. An integration operation is started from a position in which the integrated signal is located lower than the bias voltage, when an input of the gate terminal becomes a high level.

A switch control circuit and a switch control method are provided. The switch control circuit includes a load, an inductor, a control switch, and a sensing resistance connected in series to an input power; an integrator that integrates a sensing voltage and a load current setting voltage to generate an integrated signal; a comparator that compares the integrated signal and a bias voltage; a switch driver that controls the control switch based on an output of the comparator and an output of an off time controller; and a gate sensor that outputs, to the integrator, a gate sensing signal that senses a time when an input of a gate terminal of the control switch becomes a low level. An integration operation is started from a position in which the integrated signal is located lower than the bias voltage, when an input of the gate terminal becomes a high level.

A load control device for controlling the power delivered from an AC power source to an electrical load includes a thyristor, a gate coupling circuit for conducting a gate current through a gate of the thyristor, and a control circuit for controlling the gate coupling circuit to conduct the gate current through a first current path to render the thyristor conductive at a firing time during a half cycle. The gate coupling circuit is able to conduct the gate current through the first current path again after the firing time, but the gate current is not able to be conducted through the gate from a transition time before the end of the half-cycle until approximately the end of the half-cycle. The load current is able to be conducted through a second current path to the electrical load after the transition time until approximately the end of the half-cycle.

A buck boost system for allowing LED devices to be driven from a longer distance. The boost device boosts the voltage level to a higher level than that used by the eventual LED device. The buck device is powered from that higher voltage, and also reduces the voltage level to a level used by the LED device.

A buck boost system for allowing LED devices to be driven from a longer distance. The boost device boosts the voltage level to a higher level than that used by the eventual LED device. The buck device is powered from that higher voltage, and also reduces the voltage level to a level used by the LED device.

A power converter circuit may include a control circuit configured to generate a drive signal for rendering a semiconductor switch conductive and non-conductive to generate a bus voltage across a bus capacitor. The control circuit may adjust a minimum operating period of the drive signal to a first value when an output power of the power converter circuit is greater than a first threshold and to a second value when the output power is less than a second threshold. The control circuit may comprise a comparator that generates the drive signal in response to a sense voltage and a threshold voltage. When operating in a standby mode, the control circuit may adjust a magnitude of the threshold voltage based on an instantaneous magnitude of an alternating-current line voltage received by the power converter circuit, such that an input current drawn by the power converter circuit is sinusoidal.

A power converter circuit may include a control circuit configured to generate a drive signal for rendering a semiconductor switch conductive and non-conductive to generate a bus voltage across a bus capacitor. The control circuit may adjust a minimum operating period of the drive signal to a first value when an output power of the power converter circuit is greater than a first threshold and to a second value when the output power is less than a second threshold. The control circuit may comprise a comparator that generates the drive signal in response to a sense voltage and a threshold voltage. When operating in a standby mode, the control circuit may adjust a magnitude of the threshold voltage based on an instantaneous magnitude of an alternating-current line voltage received by the power converter circuit, such that an input current drawn by the power converter circuit is sinusoidal.

A multi-stage driver system includes a switched mode power circuit for providing power to different electrical load(s). Multi-stage driver system includes a control block including at least one microcontroller coupled to control operations of the switched mode power circuit. Switched mode power circuit includes a high voltage region, a low voltage region, and an isolation barrier. High voltage region of the switched mode power circuit includes a switched rectifier and a switched bridge circuit configured to produce a high voltage bidirectional pulse train signal for output to an isolation barrier. Low voltage region of the switched mode power circuit includes a rectification circuit coupled to the isolation barrier and at least one switched converter circuit coupled to the rectification circuit. Control block receives real-time input signals (e.g., analog voltage reading(s)) from the high and low voltage regions and responsively produces control signals to the high and low voltage regions.

Apparatuses, systems and methods for regulating the output currents of a power supply at a target output current include a buck converter module operably connected to a power source and a load. A first switch couples the power source to the buck converter module during a first period of a given operating cycle, while the buck converter module stores and provides electrical power to the load. During a second period, the buck converter may discharge the electrical power stored during the first period. A current sensor senses the currents during at least one of the first period and the second period and, over the operating cycle, the switching is adjusted so the average output current equals the target output current. Adjustments to the first and second period durations result in maximum and a minimum currents symmetrically disposed about the average current provided to the load during the operating cycle.