Patent application number | Description | Published |
20120154462 | REGULATION OF GAMMA CHARACTERISTIC IN A DISPLAY - System(s) and method(s) are provided for regulation of gamma characteristic of a display having solid-state-based backlight illumination. Regulation of the gamma characteristic can be accomplished at least in part through synchronization of data writing to a set of pixels in a display within a video frame with backlight illumination of a region of the display during a predetermined period, wherein the region is spanned by the set of pixels. Collection of data indicative of illumination intensity of light to be emitted in a region of a backlight source of the display during the predetermined period enables determination of at least one gamma value and at least one gamma reference voltage related to the at least one gamma value. Application of the at least one gamma reference voltage to the set of pixels adjusts the gamma characteristic thereof within the video frame. | 06-21-2012 |
20120194816 | Quality Assurance of a Solid-State Illumination Source - System(s), apparatus(es), and method(s) are provided for control of quality of light emitted from a group of solid-state light (SSL) sources that are part of an illumination fixture. The control is based at least in part on regulation of the spectral power distribution (SPD) of the light to match a SPD of a reference light source. A spectroscopic analyzer collects electromagnetic (EM) radiation emitted from the group of SSL sources and EM radiation substantially emitted from the reference light source. A first controller analyzes spectroscopic data related to SPDs of the group of SSL sources and the reference light source and, based on the analysis issues a configuration of the group of SSL sources. Implementation of the configuration causes the group of SSL sources to emit EM radiation with a SPD that nearly matches the SPD of the EM radiation substantially emitted from the reference light source. | 08-02-2012 |
20120306944 | CONTROL OF LIGHT-EMITTING-DIODE BACKLIGHT ILLUMINATION THROUGH FRAME INSERTION - System(s) and methode s) are provided to regulate backlighting in a light emitting diode (LED)-based display through a sequence of alternate pulse-width-modulation (PWM) frame or sub-frame insertions. Alternate PWM frames or sub-frames can be black or non-black. A plurality of pixels in the display is partitioned into at least one zone including one or more rows of pixels; the at least one zone determines sub-frame period based on refresh frequency of the display. A sequence of alternate PWM sub-frames includes at least one alternate sub-frame and at least one normal sub-frame. Alternate PWM frames or alternate PWM sub-frames include a phase delay during which a backlight unit is turned off, and a PWM sequence in which the backlight unit is turned on with a finite duty cycle for the remainder of the PWM frame or sub-frame. | 12-06-2012 |
20130193859 | Apparatus, Circuit and Method for Automatic Phase-Shifting Pulse Width Modulated Signal Generation - Systems, circuits and methods for phase-shifting pulse width modulated signal generation are disclosed. In some embodiments, a phase-shifting pulse width modulation circuit is configured to output pulses based on an input pulse width modulated signal. The pulses are staggered relative to one another, and can be received by a light-emitting diode driver for driving a light-emitting diode string at one or more time periods. The phase-shifting pulse width modulation circuit can include a counter-based programmable delay subcircuit consisting of two counter-based programmable delay blocks. | 08-01-2013 |
20140139126 | LOAD-AWARE COMPENSATION IN LIGHT-EMITTING-DIODE BACKLIGHT ILLUMINATION SYSTEMS - System(s) and method(s) are provided for power management in an electronic display via compensation of a power source of a light-emitting-diode (LED) backlighting system. A compensation feedback loop includes a load-aware controller that receives the bad condition from a dimming controller and supplies a control signal to the power source. An efficiency regulator functionally connected the backlight circuitry closes the compensation, feedback loop and provides an input signal to the load-aware controller. The dimming controller implements phase-shifted pulse-modulation dimming, which based on duty cycle can establish a dimming equilibrium with two load conditions. The load aware controller includes a set of compensation blocks arranged in parallel, with a single compensation block connected to the input signal and that provides the control signal. A selector component in the load aware controller determines a compensation block to be connected to the compensation feedback loop based on the received load condition. | 05-22-2014 |
20140153291 | DUAL-MODE, AC/DC POWER CONVERTER WITH POWER FACTOR CORRECTION - A dual-mode circuit for the control of an AC/DC power converter is disclosed. An example dual-mode controller circuit generates a waveform that drives a switch on or off and controls the power converter. The controller circuit in addition to power factor correction (PFC) circuitry includes a critical conducting mode (CrM) module as well as a discontinuous conducting mode (DCM) module configured to generate waveforms adapted for CrM and DCM operation of a power converter. The circuit includes a node for receiving a feedback signal of a voltage or a current. Based on the received signal, one of the modules is selected at a time to supply the waveform at the output of the dual-mode controller. An example of the output waveform is a series of pulses that are configured to drive the switch that controls the transfer of power between input and output of the power converter. | 06-05-2014 |
20140160802 | FAULT PROTECTION AND CORRECTION OF LINE AND LOAD FAULTS - A fault protection and correction circuit for the control of a power converter is disclosed. An example circuit generates a waveform that drives a switch on or off and controls the power converter. The controller circuit in addition to power factor correction (PFC) circuitry includes a first and a second shut down mode modules, both of them cause the switching to stop. The circuit includes a module for receiving fault events. When a fault occurs, the controller enters the second shut down mode. The controller stays in the second shut down mode if the required current for this mode can be provided by the outside circuitry. Otherwise, the controller enters the first shut down mode that requires less current and subsequently restarts the controller. By modifying the outside circuitry the controller can respond differently to fault events. | 06-12-2014 |
20140211518 | LOW TOTAL HARMONIC DISTORTION AND HIGH POWER FACTOR CORRECTION POWER CONVERTERS - A controller circuit for the control of a power converter is disclosed. An example controller circuit generates a waveform that drives a switch that controls the power converter. The controller circuit includes a divider module that generates a modification factor based on a ratio of the two input signals of the module. The circuit includes a module that generates a first waveform configured for a critical conducting mode of operation of a power converter and an on-time adjuster module that modifies the first waveform based on the modification factor and generates a second waveform. The second waveform is delivered to the switch. An example modification factor is the ratio of the output voltage to the rectified input voltage of the power converter. | 07-31-2014 |
20140253090 | CONFIGURABLE INTEGRATED CIRCUIT ENABLING MULTIPLE SWITCHED MODE OR LINEAR MODE POWER CONTROL TOPOLOGIES - An integrated circuit is operable for implementing any of multiple switched mode or linear power control topologies. The integrated circuit includes a control unit, and functional blocks each of which includes circuitry. The control unit is operable selectively to enable particular ones of the functional blocks in response to an input signal indicative of a particular one of the switched mode or linear mode power control topologies. | 09-11-2014 |