Abstract: An LED driver is configured to minimize power consumption during standby operating modes. The LED driver includes power factor correction (PFC) and isolated DC-DC conversion stages, driven by respective first and second regulators. An auxiliary sensor detects environmental conditions for a controller which generates standby or normal operating mode signals based thereon. A low standby isolated power supply circuit receives operating mode signals and is configured: responsive to normal operating mode signals to enable the voltage regulators; responsive to standby mode signals to disable the voltage regulators, and in both modes to supply power to the controller and auxiliary sensor. Accordingly, the controller and auxiliary sensor are continuously enabled whereas the PFC and DC-DC stages of the LED driver are disabled during standby modes. Additional circuitry may selectively disconnect voltage sensing resistance networks from the LED driver for further reductions in power consumption during standby mode.

Abstract: An apparatus and a method reduce the ripple on a load current through an LED load. The load current is provided by a flyback converter, which is responsive to a feedback signal to maintain the output current at or near a selected magnitude. The LED load has an AC resistance which is at least one cause of the ripple on the load current. A stabilizing resistor in the current path to the LED load reduces the magnitude of the ripple caused by the AC resistance. The stabilizing resistor may have a constant stabilizing resistance value for different LED loads; or the stabilizing resistor have a dynamic stabilizing resistance value such that the stabilizing resistance value is greater when the LED load has fewer LEDs and is smaller when the LED load has more LEDs.

Abstract: A driver circuit of a light fixture includes a half-bridge inverter, a resonant tank circuit, an isolating transformer, an output rectifier, and a controller. The half-bridge inverter provides an alternating current signal to the resonant tank circuit. The resonant tank circuit includes a resonant inductor, a resonant capacitor, a first clamping diode, and a second clamping diode. The clamping diodes limit the voltage of the resonant capacitor to a power rail voltage and a ground voltage. The isolating transformer is connected to the resonant tank circuit. The controller senses current provided to the light source and adjusts a switching frequency of the half-bridge inverter to maintain the sensed current at a target current. The driver circuit operates as a constant current source with a self-limited output voltage determined as a function of the voltage of the power rail and the turns ration of the isolating transformer.

Abstract: A bobbin provides secure attachment of a magnetic component to a printed circuit board. The circuit board includes a set of slotted apertures and a set of tubular apertures. The bobbin includes at least two pin rails and a plurality of standoffs proximate each pin rail. L-shaped pins are attached to one of the pin rails. Straight pins are attached to the other pin rail. The component further includes a core, and at least one winding. The L-shaped pins are shaped to pass through and slide within the set of slotted apertures. The L-shaped pins engage the bottom surface of the circuit board when the straight pins are inserted through the set of tubular apertures (i.e., in a secured position). In the secured position, the magnetic component is held in place against the top surface of the circuit board and provides a soldering area for mounting on the bottom surface.

Abstract: A system for a linear isolated power supply circuit may include a boost converter having a boost inductor winding and an auxiliary side winding, the auxiliary side winding configured to be magnetically coupled to the boost inductor winding. The linear isolated power supply circuit includes a voltage sensing circuit coupled to the auxiliary side winding, the voltage sensing circuit configured to measure an input voltage at an isolated circuit associated with the auxiliary winding. The linear isolated power supply circuit includes a processor configured to receive the measured input voltage from the voltage sensing circuit and to cause at least one operation to be performed by the processor based at least in part upon the measured input voltage. Methods and apparatuses corresponding to the system are provided.

Abstract: A lighting control system may include a main lighting controller having an opening therein and a main coupler for connecting to an expansion pack. An expansion pack of the lighting control system may have a connector having an opening therein and an expansion coupler for connecting to the main lighting controller. Junction boxes may be configured to connect to the main lighting controller and expansion pack based on a predetermined distance associated with openings of the main lighting controller and expansion pack. Installation of a combined main lighting controller and expansion pack at a plurality of junction boxes may be coordinated. A method may include combining a main lighting controller and an expansion pack, connecting two or more junction boxes to one another to form an array, and connecting the two or more junction boxes to the main lighting controller and expansion pack in accordance with a predetermined spacing.

Abstract: An AC LED driver for providing operating power to an LED load. The AC LED driver includes a first input terminal and a second input terminal, each of the first and second input terminals connectable to an AC input voltage source. The AC LED driver further includes a current limiting capacitor coupled to the first input terminal and a bridge rectifier coupled to the current limiting capacitor, the bridge rectifier having a plurality of rectifying diodes. The AC LED driver also includes a phase angle shift unit coupled to the first input terminal and the bridge rectifier, the phase angle shift unit configured to minimize a phase angle between input line current and input voltage received via at least one of the first input terminal and the second input terminal.

Abstract: A constant current source has an increased differential amplifier gain at low output currents and a decreased differential amplifier gain at high output currents. The differential amplifier amplifies a sensed output current of the constant current source. A gain control circuit scales a reference current in conjunction with the gain applied to the sensed output current to maintain stable operation of the constant current source. The constant current source may be used in a driver circuit to provide power to a light source (e.g., an LED light).

Abstract: A light fixture includes a driver circuit that fully defines operational characteristics for operation outside of “Nominal Operation” of the driver circuit. The driver circuit increases a target current or set point when the current of the light source (i.e., output current of the driver circuit) or the voltage of the light source (i.e., output voltage of the driver circuit) is below a minimum operating current or minimum operating voltage of the driver circuit regardless of a command current level of the driver circuit. The driver circuit implements a soft start ramp up scheme having a default rate of increase for a set point or target current. After a shutdown, the driver circuit periodically attempts to restart operation by increasing the set point or target current from zero (i.e., shutdown) at a reduced rate as compared to the default rate.

Abstract: An electronic ballast apparatus for powering one or more gas discharge lamps includes an inverter that is controlled by an inverter control circuit. The inverter control circuit adjusts certain ballast operating characteristics in order to operate the lamps under nearly the same operating conditions irrespective of how many lamps are connected to the ballast. The inverter control circuit includes a lamp quantity sensor, a regulator circuit and an end-of-lamp-life sensor. The lamp quantity sensor provides a lamp quantity signal that indicates how many lamps are connected to the ballast. The regulator circuit includes a reference adjustment circuit that receives the lamp quantity signal and provides a scaled reference signal to a reference terminal of an error amplifier. The error amplifier also has a feedback terminal that receives a signal that is proportional to the power delivered by the inverter to the lamps.