Abstract: 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 load 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.

Abstract: 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.

Abstract: System(s) and method(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. A sequence of alternate PWM sub-frames can be configured internally or externally.

Abstract: System(s) and method(s) are provide to efficiently assess performance of a set of light emitting diode (LED) strings in an illumination system. A multiplexer component collects input signal from the one or more LED strings via a first set of one or more monitoring pins, processes the collected input signal, and extracts at least one output signal. The at least one output signal is conveyed to a demultiplexer component through a second set of one or more monitoring pins, wherein the number of elements in the second set of monitoring pins is equal to or smaller than the number of monitoring pins in the first set. The collected input signal is processed in accordance with at least one mode of operation of the multiplexer component, the mode of operation autonomously configured by the demultiplexer component. The multiplexer component can autonomously generate intelligence on operating status of the set of LED strings.

Abstract: Integrated backlight unit (BLU) and liquid crystal systems and circuits in liquid crystal display (LCD) systems are described. An LCD system can include a BLU to emit light at different intensities, and a BLU controller coupled to the BLU and configured to control the intensities. An LCD unit can receive the emitted light, and emanate light at a selected luminosity. The LCD unit can include pixels corresponding to: a liquid crystalline medium to provide a transmittance of the light emitted or to transmit a color light; and transistors adapted to modulate reference voltages. An LCD unit controller can be coupled to the LCD unit and configured to control luminosity of the light emanated from the LCD unit. The BLU and the LCD unit, which can be integrated in a single integrated circuit, can be controlled during concurrent time periods for contrast enhancement of images displayed from the LCD unit.

Abstract: The innovation relates to systems and/or methodologies for error detection during sub-assembly in high voltage analog circuits. A signal driver communicates test signals to one or more high voltage analog circuits, and a state machine compares the electrical and/or thermal responses of the high voltage analog circuits to a set of predetermined expected results (e.g., signatures). The signal driver and state machine can be incorporated into the high voltage analog circuits. The expected results can be stored in the target circuits in the form of look-up tables, matrices, and so forth. Errors, such as, dry solders and bridge solders can be determined based on the comparison of the obtained responses to the expected signatures.

Abstract: The present invention relates to circuits and methods for controlling one or more LED strings. The circuit comprises a programmable controller coupled to one or more detectors, wherein the one or more detectors are configured to detect one or more measurable parameters of one or more LEDs or LED drivers. The controller is configured to receive information from the one or more detectors related to the one or more measurable parameters and use that information to determine the desired drive voltage for the LED strings. The controller is associated with a power supply having power factor correction (PFC) capability. The controller provides the power supply with a control signal indicative of the desired drive voltage for one or more LED strings. The power supply also receives ac voltage and current waveforms as inputs and performs power factor correction and rectified waveforms related to the ac waveforms. The power supply generates the desired drive voltage based on the control signal.

Abstract: The present invention relates to circuits and methods for controlling one or more LED strings. The circuit comprises a programmable controller coupled to one or more detectors, wherein the one or more detectors are configured to detect one or more measurable parameters of one or more LEDs or LED drivers. The controller is configured to receive information from the one or more detectors related to the one or more measurable parameters and use that information to determine the desired drive voltage for the LED strings. The controller is associated with a power supply having power factor correction (PFC) capability. The controller provides the power supply with a control signal indicative of the desired drive voltage for one or more LED strings. The power supply also receives ac voltage and current waveforms as inputs and performs power factor correction and rectified waveforms related to the ac waveforms. The power supply generates the desired drive voltage based on the control signal.

Abstract: The present invention uses two transistors instead of a sensing resistor to provide a constant current source for a load such as an array of light emitting diodes (“LEDs”). In the present invention, a bias current is applied to a branch of the circuit. The drain-to-source voltages of two transistors are matched. The voltage at the gate of both transistors is controlled based on the bias current and the drain-to-source current of the first of the two transistors. The second of the two transistors is sized such that source current of the second transistor is a multiple of the source current of the first transistor for a given gate voltage. By the techniques of this invention, the load current in a circuit is efficiently kept constant at a multiple of the input bias current.