Patent application number | Description | Published |
20090243582 | PHASE-CUT DIMMING CIRCUIT - Methods, systems, and devices are described for sensing a phase-cut dimming signal and outputting a control signal compatible with a switching power circuit. Embodiments of the invention generate at least one of a low-frequency pulse-wave-modulated control signal, an analog output control signal, or a digital (e.g., higher-frequency pulse-wave-modulated) output control signal. Some embodiments further provide preloading and/or startup control functionality to allow proper functioning of the circuitry under small-conduction-angle (i.e., highly dimmed) conditions. | 10-01-2009 |
20100033146 | CURRENT SENSING FOR HIGH VOLTAGE BUCK CONVERTER - Methods, systems, and devices are described for providing output (e.g., current) sensing and feedback in high-voltage switching power converter topologies. Certain aspects of high voltage switching converter topologies may make output (e.g., current) sensing difficult. In some embodiments, a sampling module implements sample-and-hold techniques in a low-side switch converter topology to provide reliable current sensing. Embodiments of the sampling module provide certain functionality, including integration, blanking, buffering, and adjustable sampling frequency. Further, some embodiments include feedback functionality for generating a converter driver signal (for driving the switching converter) and/or a sample driver signal (for driving the sampling module) as a function of sensed output feedback from the sampling module. | 02-11-2010 |
20100033150 | BUS VOLTAGE OPTIMIZER FOR SWITCHED POWER CONVERTER - Methods, systems, and devices are provided for optimizing a bus voltage supplied to a switching power converter to keep the duty cycle of the switching power converter to within a desirable operating range. In some embodiments, the duty cycle of the switching signal used to drive the switching power converter is monitored (e.g., indirectly) to determine whether the duty cycle is approaching an undesirable level. For example, as the duty cycle decreases (e.g., approaches or crosses a certain threshold), embodiments decrease the bus voltage. This may, in turn, allow the switching power converter to output substantially the same output to the load, while using a more efficient (e.g., larger) duty cycle. Certain embodiments use similar techniques, along with certain bus voltage optimization techniques, to control a bus voltage as a function of feedback from multiple switching power converters. | 02-11-2010 |
20120098505 | PHASE-CUT DIMMING CIRCUIT - Methods, systems, and devices are described for sensing a phase-cut dimming signal and outputting a control signal compatible with a switching power circuit. Embodiments of the invention generate at least one of a low-frequency pulse-wave-modulated control signal, an analog output control signal, or a digital (e.g., higher-frequency pulse-wave-modulated) output control signal. Some embodiments further provide preloading and/or startup control functionality to allow proper functioning of the circuitry under small-conduction-angle (i.e., highly dimmed) conditions. | 04-26-2012 |
20120242304 | Source Driver Current Fold-Back Protection - A load current is limited to a safe level with a current protection logic circuit within a first selected interval after detection of a fault condition. The current protection logic circuit returns the load current to a normal level within a second selected interval after correction of the fault condition, wherein said safe level is less than one half of the normal level. The current protection logic circuit is a feature of a high side driver comprising at least two source drivers, each source driver being configured to switch an electrical load to a common power supply, and comprising a respective current protection logic circuit. | 09-27-2012 |