Patent application number | Description | Published |
20090230874 | LED DRIVER WITH SEGMENTED DYNAMIC HEADROOM CONTROL - Techniques for dynamic headroom control in a light emitting diode (LED) system are disclosed. An output voltage is provided to drive a plurality of LED strings. A feedback controller monitors the tail voltages of the LED strings to identify the minimum tail voltage and adjusts the output voltage based on the lowest tail voltage. The LED strings grouped into subsets and the feedback controller is segmented such that, for a certain duration, a minimum tail voltage is determined for each subset. The minimum tail voltages of the subsets are used to determine the overall minimum tail voltage of the plurality of LED strings for the certain duration so as to control the output voltage in the following duration. The segments of the feedback controller can be implemented in separate integrated circuit (IC) packages, thereby facilitating adaptation to different numbers of LED strings by integrating the corresponding number of IC packages. | 09-17-2009 |
20090230891 | LED DRIVER WITH DYNAMIC POWER MANAGEMENT - Power management in a light emitting diode (LED) system having a plurality of LED strings is disclosed. A voltage source provides an output voltage to drive the LED strings. An LED driver monitors the tail voltages of the active LED strings to identify the minimum, or lowest, tail voltage and adjusts the output voltage of the voltage source based on the lowest tail voltage. The LED driver can adjust the output voltage so as to maintain the lowest tail voltage at or near a predetermined threshold voltage so as to ensure that the output voltage is sufficient to properly drive each active LED string with a regulated current in view of pulse width modulation (PWM) performance requirements without excessive power consumption. | 09-17-2009 |
20090273288 | LED DRIVER WITH DYNAMIC POWER MANAGEMENT - A light emitting diode (LED) system implements a LED driver to drive a set of one or more LED strings. The LED driver includes a voltage source to provide an adjustable output voltage to a head end of each LED string of the set for a first duration and a second duration following the first duration. The LED driver further includes a feedback controller to control the voltage source to adjust the output voltage for the second duration based on a digital code value generated from a minimum tail voltage of one or more tail voltages of the set at a sample point of the first duration. The LED driver further includes a power controller to temporarily enable one or more components of the feedback controller for a sample period of the first duration, the sample period comprising the sample point. | 11-05-2009 |
20100026203 | LED DRIVER WITH FRAME-BASED DYNAMIC POWER MANAGEMENT - Disclosed are example techniques for frame-based power management in a light emitting diode (LED) system having a plurality of LED strings. A voltage source provides an output voltage to drive the LED strings. An LED driver generates a frame timing reference representative of the frame rate or display timing of a series of image frames to be displayed via the LED system. An update reference is generated from the frame timing reference. The LED driver monitors one or more operating parameters of the LED system. In response to update triggers marked by the update reference, the LED driver adjusts the output voltage of the voltage source based on the status of each of the one or more monitored operating parameters (either from the previous update period or determined in response to the update trigger), thereby synchronizing the updating of the output voltage to the frame rate (or a virtual approximation of the frame rate) of the video being displayed. | 02-04-2010 |
20100156315 | LED DRIVER WITH FEEDBACK CALIBRATION - Power management in a light emitting diode (LED) system having a plurality of LED strings is disclosed. A voltage source provides an output voltage to drive a plurality of LED strings. An LED driver implements a feedback mechanism to monitor the tail voltages of the active LED strings to identify the minimum tail voltage and adjust the output voltage of the voltage source based on the lowest tail voltage. A loop calibration module of the LED driver calibrates the feedback mechanism of the LED driver based on a relationship between a digital code value used to generate a particular output voltage and another digital code value generated based on the minimum tail voltage resulting from the particular output voltage. | 06-24-2010 |
20100194308 | LED DRIVER WITH DYNAMIC HEADROOM CONTROL - A voltage source provides an output voltage to drive a plurality of light emitting diode (LED) strings. A LED driver adjusts the level of the output voltage so as to maintain the lowest tail voltage of the LED strings at or near a predetermined threshold voltage so as provide sufficient headroom voltages for current regulators for the LED strings. The LED driver operates in an operational mode and a calibration mode, which can be implemented in parallel with, or part of, the operational mode. During the calibration mode, the LED driver determines, for each LED string, a code value representative of the level of the output voltage necessary to maintain the tail voltage of the corresponding LED string at or near the predetermined threshold voltage. In the operational mode, the code values from the calibration mode are used to control the voltage source to provide an appropriate level for the output voltage. | 08-05-2010 |
20120207205 | PHASE-SHIFTED PULSE WIDTH MODULATION SIGNAL GENERATION DEVICE AND METHOD THEREFOR - First information is received at a first pulse width modulation (PWM) module responsive to a chip select signal being asserted at a chip select input of a communication bus of the first PWM module during a first time. The first information is latched at a control register of the first PWM module in response to a first logic transition of the chip select signal. A first PWM signal is provided at a first output of the first PWM module beginning a predetermined amount of time after the first logic transition of the chip select signal, the first PWM signal generated by the first PWM module based upon the first information. | 08-16-2012 |
Patent application number | Description | Published |
20110047052 | Method and process for an energy management system for setting and adjusting a minimum energy reserve for a rechargeable energy storage device - An energy management system which will allow the owner to set a minimum energy reserve or charge for an energy storage device (ESD), such ESD being coupled to an asset that is further connected to the electric utility grid. A plurality of sensors may be utilized to provide data, including ESD health and ambient conditions, so that, along with other owner data inputs and profile information, an appropriate amount of energy may be charged to and maintained in the ESD to enable the associated asset to perform anticipated tasks. The energy management system may be either directly or remotely programmed via secure communications, and will further provide the owner with the ability to discharge energy back to the grid during demand events, or to discharge to other owner specified assets, at the owner's discretion. | 02-24-2011 |
20120233062 | Method and process for an electric vehicle charging system to automatically engage the charging apparatus of an electric vehicle - An automated vehicle charging system, that may be done within a service type station, to provide for charging, recharging, or even discharging, of the batteries of an electric vehicle, and generally will include a dispenser, having a cabinet containing all of the instrumentation desired for furnishing the provision of current information relative to the charging of a vehicle, of otherwise, and will include boom means that are highly maneuverable, in order to bring the charging instrument into close proximity of the electrical receptacle of the vehicle being serviced, whether it be at a service type station, or at a curbside type of charging system. Robotics may be used within the structure of these electrical charging systems, to facilitate the charging of any vehicle, by the customer itself, even at a self service type of station. | 09-13-2012 |
20140067660 | Method and process for an electric vehicle charging system to automatically engage the charging apparatus of an electric vehicle - An automated vehicle charging system, that may be done within a service type station, to provide for charging, recharging, or even discharging, of the batteries of an electric vehicle, and generally will include a dispenser, having a cabinet containing all of the instrumentation desired for furnishing the provision of current information relative to the charging of a vehicle, of otherwise, and will include boom means that are highly maneuverable, in order to bring the charging instrument into close proximity of the electrical receptacle of the vehicle being serviced, whether it be at a service type station, or at a curbside type of charging system. Robotics may be used within the structure of these electrical charging systems, to facilitate the charging of any vehicle, by the customer itself, even at a self service type of station. | 03-06-2014 |