Abstract: A pair of eyeglasses may include one or more adjustable lenses. An adjustable lens may include electrically modulated optical material such as one or more liquid crystal cells having a phase profile that is adjusted using patterned electrodes. Digital-to-analog converter circuits may provide voltages to the electrodes. To save space on the lens, a smaller number of digital-to-analog converter circuits may provide voltages to a greater number of electrodes by sequentially coupling and decoupling the digital-to-analog converter circuits to different groups of electrodes, advancing from group-to-group with each clock cycle by a number of electrodes that is less than the number of digital-to-analog converter circuits. At least one of the electrodes in each group may be driven at the same voltage for two consecutive clock cycles to avoid erroneous voltages resulting from the parasitic capacitance between adjacent fingers.

Abstract: Systems and methods for operating a display by dynamically determining a refresh rate for the display. In certain implementations, a processor determines a number of pixels having medium grayscale levels from a histogram for the image. If the number does not exceed a threshold, the processor sets a refresh rate for the display to a first refresh rate. In certain implementations, if the number exceeds a threshold, the processor may set the refresh rate for the display to a second refresh rate. Moreover, the first refresh rate may be lower than the second threshold. In some implementations, the image may be analyzed by subdividing the image into blocks and determining a refresh rate based on grayscale levels or distributions in the blocks. Based on the analysis of the blocks, a corresponding refresh rate may be selected.

Abstract: The disclosed embodiments provide a system that operates a power supply. During operation, the system obtains power states of two or more loads coupled to two or more power converters in the power supply. Next, the system generates one or more control signals for a set of switching mechanisms to configure a coupling of the two or more loads to the two or more power converters through the switching mechanisms based on the power states.

Abstract: The disclosed embodiments provide a system that operates a power supply. During operation, the system disposes a first switching mechanism between a first output of a first power converter and two or more loads. Next, the system obtains two or more error signals for the two or more loads, wherein each error signal from the two or more error signals represents a difference between a load voltage of a load from the two or more loads and a first reference voltage for the load from a first set of reference voltages for driving the two or more loads using the first power converter. The system then uses the first switching mechanism to couple the load with a largest error signal from the two or more error signals to the first output.

Abstract: Embodiments of an adapter are disclosed that include a rectifier with an input and an output coupled to a step-down transformer with a primary coil and a secondary coil, wherein the primary coil is coupled to the output of the rectifier. A step-up converter is coupled to the secondary coil.

Abstract: In some embodiments, a system may include at least one voltage controller. At least one of the voltage controllers may assess, during use, an occurrence of a predetermined condition. In some embodiments, the system may include an at least first capacitor. The at least first capacitor may be coupled to at least one of the voltage controllers such that at least one of the voltage controllers engages the at least first capacitor to supply additional current when the predetermined condition occurs. When the increase in current is no longer required the at least first capacitor may be disengaged. The at least first capacitor may be charged when disengaged until a predetermined capacity.

Abstract: The disclosed embodiments provide a system that operates a power supply. During operation, the system disposes a first switching mechanism between a first output of a first power converter and two or more loads. Next, the system obtains two or more error signals for the two or more loads, wherein each error signal from the two or more error signals represents a difference between a load voltage of a load from the two or more loads and a first reference voltage for the load from a first set of reference voltages for driving the two or more loads using the first power converter. The system then uses the first switching mechanism to couple the load with a largest error signal from the two or more error signals to the first output.

Abstract: Systems and methods for operating a display by dynamically determining a refresh rate for the display. In certain implementations, a processor determines a number of pixels having medium grayscale levels from a histogram for the image. If the number does not exceed a threshold, the processor sets a refresh rate for the display to a first refresh rate. In certain implementations, if the number exceeds a threshold, the processor may set the refresh rate for the display to a second refresh rate. Moreover, the first refresh rate may be lower than the second threshold. In some implementations, the image may be analyzed by subdividing the image into blocks and determining a refresh rate based on grayscale levels or distributions in the blocks. Based on the analysis of the blocks, a corresponding refresh rate may be selected.

Abstract: One gate driver includes an output node configured to be coupled to a gate line and to provide power to the gate line for driving thin-film transistor (TFT) gates of a display. An input node of the gate driver is configured to receive an input signal. The gate driver includes a first field-effect transistor (FET) having a gate, a drain, and a source. The drain may be coupled to the input node and the source may be coupled to the output node. The gate driver also includes a second FET having a gate, a drain, and a source. The drain may be coupled to the input node. The gate driver includes a capacitor having a first end coupled to the gates of the FETs and a second end coupled to the source of the second FET. Using the gate driver power consumption of the display may be reduced.

Abstract: The disclosed embodiments provide a system that operates a power supply. During operation, the system obtains power states of two or more loads coupled to two or more power converters in the power supply. Next, the system generates one or more control signals for a set of switching mechanisms to configure a coupling of the two or more loads to the two or more power converters through the switching mechanisms based on the power states.

Abstract: An adapter for electrical power that includes a rectifier coupled to a transformer with a primary coil and a secondary coil. The secondary coil includes a first end tap, a second end tap, and a center tap. A first switch is coupled between the first end tap and a primary side ground. A second switch is coupled between the second end tap and the primary side ground. A controller is coupled to the first switch and to the second switch so that during one or more intervals, the first switch and the second switch are alternately open and closed a predetermined number of times, wherein the initial switch closed each interval alternates between the first switch and the second switch, and after the predetermined number of times, both the first switch and the second switch are opened for a predetermined time period.

Abstract: One gate driver includes an output node configured to be coupled to a gate line and to provide power to the gate line for driving thin-film transistor (TFT) gates of a display. An input node of the gate driver is configured to receive an input signal. The gate driver includes a first field-effect transistor (FET) having a gate, a drain, and a source. The drain may be coupled to the input node and the source may be coupled to the output node. The gate driver also includes a second FET having a gate, a drain, and a source. The drain may be coupled to the input node. The gate driver includes a capacitor having a first end coupled to the gates of the FETs and a second end coupled to the source of the second FET. Using the gate driver power consumption of the display may be reduced.

Abstract: In some embodiments, a system may include at least one voltage controller. At least one of the voltage controllers may assess, during use, an occurrence of a predetermined condition. In some embodiments, the system may include an at least first capacitor. The at least first capacitor may be coupled to at least one of the voltage controllers such that at least one of the voltage controllers engages the at least first capacitor to supply additional current when the predetermined condition occurs. When the increase in current is no longer required the at least first capacitor may be disengaged. The at least first capacitor may be charged when disengaged until a predetermined capacity.

Abstract: Embodiments of an adapter are disclosed that include a transformer with a primary coil coupled to an H-bridge. The H-bridge is controlled by a control circuit that controls a voltage across the primary coil using the H-bridge, and the control circuit is configured to control the H-bridge so that during each of one or more intervals, a first voltage pulse is applied across the primary coil in a start direction, wherein the start direction alternates between a first direction and a second direction each interval. Then, a direction of subsequent voltage pulses across the primary coil is alternated between the first direction and the second direction a predetermined number of times. After the predetermined number of times, a last voltage pulse is applied across the primary coil; then, voltage across the primary coil is reduced to zero for a predetermined time.

Abstract: Embodiments of an adapter are disclosed that include a transformer with a primary coil coupled to an H-bridge. The H-bridge is controlled by a control circuit that controls a voltage across the primary coil using the H-bridge, and the control circuit is configured to control the H-bridge so that during each of one or more intervals, a first voltage pulse is applied across the primary coil in a start direction, wherein the start direction alternates between a first direction and a second direction each interval. Then, a direction of subsequent voltage pulses across the primary coil is alternated between the first direction and the second direction a predetermined number of times. After the predetermined number of times, a last voltage pulse is applied across the primary coil; then, voltage across the primary coil is reduced to zero for a predetermined time.

Abstract: An adapter for electrical power that includes a rectifier coupled to a transformer with a primary coil and a secondary coil. The secondary coil includes a first end tap, a second end tap, and a center tap. A first switch is coupled between the first end tap and a primary side ground. A second switch is coupled between the second end tap and the primary side ground. A controller is coupled to the first switch and to the second switch so that during one or more intervals, the first switch and the second switch are alternately open and closed a predetermined number of times, wherein the initial switch closed each interval alternates between the first switch and the second switch, and after the predetermined number of times, both the first switch and the second switch are opened for a predetermined time period.

Abstract: Embodiments of an adapter are disclosed that include a rectifier with an input and an output coupled to a step-down transformer with a primary coil and a secondary coil, wherein the primary coil is coupled to the output of the rectifier. A step-up converter is coupled to the secondary coil.

Abstract: Embodiments of a power supply are disclosed that include a first voltage converter having a first feedback controller and a first regulated output, and second voltage converter having a second feedback controller and a second regulated output electrically coupled to the first regulated output. The power limit of the first voltage converter is lower than the power limit of the second voltage converter, and a reference voltage for the first feedback controller is higher than the reference voltage for the second feedback controller.

Abstract: A process for fabricating an integrated group III nitride structure comprising high electron mobility transistors (HEMTs) and Schottky diodes, and the resulting structure, are disclosed. Integration of vertical junction Schottky diodes is enabled, and the parasitic capacitance and resistance as well as the physical size of the diode are minimized. A process for fabricating an integrated group III nitride structure comprising double-heterostructure field effect transistors (DHFETs) and Schottky diodes and the resulting structure are also disclosed.

Abstract: A process for fabricating an integrated group III nitride structure comprising high electron mobility transistors (HEMTs) and Schottky diodes, and the resulting structure, are disclosed. Integration of vertical junction Schottky diodes is enabled, and the parasitic capacitance and resistance as well as the physical size of the diode are minimized. A process for fabricating an integrated group III nitride structure comprising double-heterostructure field effect transistors (DHFETs) and Schottky diodes and the resulting structure are also disclosed.