Abstract: An electronic that includes an integrated circuit (IC) configured to regulate an output voltage for powering a light emitting diode (LED). A first transistor is configured to be switched on or off by the IC to inductively couple or decouple a main power supply bus voltage from a primary winding of a transformer to a secondary winding of the transformer connectable to the LED. A second transistor is coupled between the IC and the main power supply bus voltage, and configured to be switched on or off by the IC to selectively provide an IC power supply input voltage to the IC.

Abstract: An data transmission method is provided for transmitting analog data through an isolating device using a calibration input pulse and a data input pulse. The analog data may represent, for example, the desired dimming value for a flyback converter powering a solid state lighting system.

Abstract: A power supply control system delivers regulated power to a load via a delivery cable. The power supply control system includes a power stage operable to deliver power to the load at a first regulated voltage level and a second regulated voltage level. A cable offset voltage unit generates an offset voltage signal representing a drop in voltage across the delivery cable. The offset voltage signal is generated based on a first cable drop compensation value when the power stage is operated to deliver power at the first regulated voltage level and based on a second cable drop compensation value when the power stage is operated to deliver power at the second regulated voltage level. A controller coupled to the power stage and the cable offset voltage unit controls the power stage to deliver the regulated power to the load based at least in part on the offset voltage signal.

Abstract: A switching power converter is provided that extrapolates from a reference voltage during dead periods of a rectified input voltage as determined from a comparison of an Isense voltage to a current threshold.

Abstract: A multiphase switching converter with a plurality of phase circuits coupled with a common output node is presented. Each phase circuit has a drive signal generator to generate a separate drive signal for a switching element of the respective phase based on a feedback signal from the common output node. Multiple voltage loops with different bandwidths or hysteresis are suggested for a multiphase power converter. In embodiments, this allows a slow phase (‘Master’) with a big inductor and low switching frequency and one or multiple fast phases (‘Slaves’) with small inductors and high switching frequency. The Master phase will allow the system to have high efficiency at low output load, while the Slave phase(s) will deliver extra current during load transient and for higher loads.

Abstract: A system is disclosed which provides the minimization of peak-to-peak output voltage ripple in multi-phase DC-DC switching converters, with two or more different value inductors (asymmetric inductors), by the optimization of phase-shifting determined by the inductance on each phase. An object of the disclosure is to ensure both the AC accuracy of the output voltage and the efficiency of the DC-DC switching converter is increased. The output voltage ripple improvement is shown to be dependent on the duty-cycle. Another object of the disclosure is to minimize the total inductor current ripple and improving the efficiency of the DC-DC switching converter by reducing the capacitor loss. Still another object of the disclosure is to minimize the output voltage ripple in the multi-phase DC-DC switching converter by ensuring the sum of the inductor current vectors is equal to zero.

Abstract: A high precision voltage reference circuit is disclosed which replaces two current bias sources, with a single current mirror. Curvature-error correction is established with a modified current mirror circuit. Another object of this disclosure is the addition of a MOSFET device, to alleviate the output voltage variation, due to the channel modulation effect of the origin of the voltage reference.

Abstract: A linear regulator is presented. It comprises a first amplifier stage, one of the inputs being coupled with the output of the linear regulator. It has an intermediate amplifier stage. The input of the intermediate amplifier stage is coupled to the output of the first amplifier stage. It has a driver stage having a pass device driven by the output of the driver stage. The output of the pass device provides the output of the linear regulator. The regulator has a voltage-to-current feedback circuit coupled with the driver stage and the output of the first amplifier stage for regulating the output resistance of the first amplifier stage depending on load conditions of the linear regulator. The voltage-to-current feedback circuit has a transistor and a current limitation circuit to limit the regulation of the output resistance of the first amplifier stage to low load conditions of the linear regulator.

Abstract: A voltage or current regulated power converter for charging batteries, is described. The power converter comprises an inductor (L), a capacitor cell (C1, C2), switches (S1, S2, S3, S4, S5, S6, S7, S8) and a controller. The controller controls the switches such that a commutation cycle of the power converter comprises a first phase, during which the capacitor cell and the inductor are arranged in series and during which a voltage across the serial arrangement of the capacitor cell and the inductor corresponds to Vin?Vout; a second phase, during which the capacitor cell and the inductor are arranged in series and during which the voltage across the serial arrangement of the capacitor cell and the inductor corresponds to ?Vout; and a third phase, during which the capacitor cell is floating and during which the voltage across the inductor corresponds to Vin?Vout or to ?Vout.

Abstract: A switching power converter is provided that cycles a power switch during a group pulse mode of operation to produce a train of pulses within a group period responsive to a control voltage being within a group mode control voltage range. Depending upon the control voltage, the number of pulses in each train of pulses is varied to provide a linear power delivery to the load.

Abstract: A power supply can be operated in a low power mode by adjusting the pulses provided to a power supply switch until a pulse resulting in a reduced amount of power that exceeds a minimum power threshold required by a load coupled to the power supply switch is identified. For each successive switching cycle, a pulse causing a lower power to be provided to the load is produced. When a pulse is produced that causes a power to be provided to the load that does not exceed the minimum power threshold required by the load, a subsequent pulse is produced that causes a greater power to be provided to the load than the previous pulse. If the greater power exceeds the minimum power threshold, the subsequent pulse is stored and similar pulses are provided for the remainder of the low power mode.

Abstract: A charging system for a battery of an electronic device is described. The charging system comprises an adapter configured to derive a transfer current at a transfer voltage from a power source. Furthermore, the charging system comprises a battery charger configured to charge a battery of the electronic device with a battery current at a battery voltage using the transfer current at the transfer voltage. In addition, the charging system comprises power transmission means configured to transmit the transfer current at the transfer voltage to the battery charger. In addition, the charging system comprises communication means configured to transmit feedback information which is indicative of the battery voltage and/or battery current from the battery charger to the adapter. The adapter is configured to set the transfer voltage and/or transfer current in dependence of the feedback information.

Abstract: A switched-mode power converter with current limit circuits for limiting the input current into the power converter and/or the output current is presented. The power converter contains a feedback loop for controlling the output voltage of the converter. A first voltage comparison unit within the feedback loop compares an output voltage with a reference voltage and outputs an error voltage based on the comparison. The power converter also contains a current control unit for limiting the input/output current. The current control unit contains a current comparison unit and a connection unit. The current comparison unit compares the input/output current with a current threshold and outputs an intermediate voltage based on the comparison. The connection unit connects the output of the current comparison unit and the output of the current comparison unit to the output of the first voltage comparison unit if the input/output current exceeds the current threshold.

Abstract: The embodiments disclosed herein describe a set of fault detection circuits for LED circuits in an LED channel. A first fault detection circuit is configured to detect a short fault across one or more LEDs. A second fault detection circuit is configured to detect an open fault across an LED. A third fault detection circuit is configured to detect a short across an LED channel transistor. A fourth fault detection circuit is configured to detect an LED channel sense resistor open fault. A fifth fault detection circuit is configured to detect if the LED channel is being intentionally unused. These fault detect circuits can be implemented in a fault detection integrated circuit coupled to the LED channel.

Abstract: This application relates to an active diode circuit for letting current pass in one direction and blocking current in the opposite direction. The active diode circuit comprises a transistor, a control voltage generation circuit for generating a control voltage that is supplied to a control terminal of the transistor, and a sensing circuit for detecting a quantity indicative of a current flowing through the transistor. The control voltage generation circuit generates the control voltage in dependence on the detected quantity. The application further relates to a method of controlling a transistor to function as an active diode so that current may pass in one direction and is blocked in the opposite direction.

Abstract: The present document relates to power transformers for electronic computing devices. In particular, a power converter configured to convert electrical power at a DC input voltage Vin into electrical power at a DC output voltage is described. The power converter comprises a plurality of flying capacitors, and a plurality of switches which are configured to arrange the plurality of flying capacitors in accordance to a sequence of operation phases. The power converter comprises a control unit configured to control the plurality of switches to repeat the sequence of operation phases at a duty cycle frequency. The plurality of flying capacitors is arranged in series during the operation phases of the sequence of operation phases. The sequence of operation phases comprises at least two operation phases during which the plurality of flying capacitors is arranged in a different order.

Abstract: A variable-level flyback power converter is configured to provide an accurate output voltage at various regulation levels. The variable-level flyback power converter may include a switch coupled to a secondary winding of a transformer, a diode coupled to a primary winding of the transformer, and a controller coupled to the switch. The controller may scale an initial reference voltage based on a desired output voltage and a forward voltage drop across the diode, compare the scaled reference voltage with a feedback voltage sensed at an auxiliary winding of the transformer to generate an error signal, and modulate a pulse signal provided to the switch based on the error voltage.

Abstract: A system is disclosed which provides a dynamic current limit circuit that accurately defines both the lower and the upper limits for the current limit. The circuit ensures both the lower and upper current limits are well-controlled. The lower current limit is matched to the normal pulse-frequency modulation (PFM) limit, and the upper current limit is matched to the pulse-width modulation (PWM) limit. This implementation has several key benefits, including making the peak current limit accurate in both sync and dynamic sleep modes. If the scheme is carefully designed, the dynamic sleep current limit gives the best load transient response.

Abstract: A switching power converter controller is provided that transitions between constant voltage pulse frequency modulation operation and constant current operation responsive to a comparison of a peak voltage for the constant voltage pulse frequency modulation operation and a peak voltage for the constant current operation.

Abstract: A flyback converter is provided with a controller that is configured to analyze the reflected feedback voltage waveforms to determine the presence of a ground connection fault for the auxiliary winding.