Abstract: A flyback converter includes a primary-side switch that controls conduction of current on a primary side of a transformer and a synchronous rectifier on a secondary side of the transformer. A synchronous rectifier driver controls the conduction of the synchronous rectifier by adaptively adjusting a turn-off threshold of the synchronous rectifier.

Abstract: A single-ended primary-inductor converter (SEPIC) circuit has at least a circuit input node and a circuit common node, and includes an inductor, a first coupling capacitor, an isolation transformer, a controllable switch, a second coupling capacitor, and a clamp diode. The inductor is electrically connected in series between the circuit input node and the first coupling capacitor. The first coupling capacitor is connected in series between the inductor and the first primary input terminal. The controllable switch is electrically connected in series between an internal circuit node and the circuit common node, and the internal circuit node is located between the inductor and the first coupling capacitor. The second coupling capacitor is electrically connected in series between the second primary input terminal and the circuit common node. The clamp diode is electrically connected in series between the internal circuit node and the second primary input terminal.

Abstract: The present invention relates to a power converter including a transformer; a current doubler including a switch element and connected to a secondary side of the transformer to double a current of the transformer according to an operation of the switch element; and a voltage resonator connected to the switch elements, wherein the voltage resonator includes a switch element and a capacitor which are connected to each other in series.

Abstract: The present disclosure provides a low dropout linear voltage regulator, including: an amplifier, configured to have a first input end receiving a reference voltage, a second input end configured to receive a feedback voltage, and an output end connected to a first node; an output transistor, having a control end connected to the first node, a first end connected to a first power source potential, and a second end connected to a second node and configured to provide an output voltage; a feedback circuit, connected to the second node and configured to provide the feedback voltage according to the output voltage; and a compensation circuit, comprising at least one of a first compensation amplifier, a second compensation amplifier and a first variable current source. The compensation circuit detects and suppresses a voltage transient generated when a load switching from light to heavy occurs at the second node.

Abstract: An insulated synchronous rectification DC/DC converter is provided. A feedback circuit drives a light-emitting element of a first photocoupler such that the output voltage VOUT of the DC/DC converter approaches a target voltage. A primary side controller is coupled to a light-receiving element of the first photocoupler, so as to switch on and off a switching transistor according to a feedback signal VFB. A synchronous rectification controller controls a synchronous rectification transistor. Upon detecting the occurrence of a switching-incapable state in the synchronous rectification transistor, a protection circuit instructs the primary side controller to stop the switching operation of the switching transistor.

Abstract: Methods, systems and apparatuses for voltage regulation are disclosed. For an embodiment, a voltage regulator includes a power source block configured to convert an input voltage to an output voltage to supply current to an output load, a storage capacitor, and an active filter configured to transfer energy between the output load and the storage capacitor. A conversion ratio of the active filter is controlled by a parameter related to the output voltage, and a conversion ratio of the power source block is at least partially controlled by a parameter related to the voltage on the storage capacitor.

Abstract: A method and apparatus for performing adaptive input current control in an electronic device are provided, where the method may include the steps of: before limiting an input current of a regulator of the electronic device to a target current value, monitoring the input current of the regulator according to a reference current, and decreasing the reference current, to make the reference current change starting from one of a plurality of predetermined reference current values, wherein the input current is obtained from a power source; detecting an input voltage of the regulator to generate a detection signal, to selectively trigger limiting output power of the regulator; and at a time point when the reference current becomes smaller than the input current, limiting the input current of the regulator to the target current value with a latest reference current value of the reference current being utilized as the target current value.

Abstract: A power supply system and related method for providing a regulated DC output from an unregulated AC input includes a Vienna rectifier having power factor correction circuitry and a series resonant DC to DC converter to provide a regulated DC output. The power supply system further includes one or more compensator circuits coupled in feedback configuration to control the Vienna rectifier and/or the DC to DC converter and avoid a potentially dangerous over-voltage condition at the regulated DC output.

Abstract: Disclosed herein are an apparatus for controlling a switch-mode power supply, and a method of operating the same. In an embodiment, it is determined whether or not a current of an inductor of the switching power supply has become less than or equal to a predetermined value. In an embodiment, a variable reference voltage is adjusted based on the current of the inductor and an output voltage. In an embodiment, a switch is turned off based on the inductor current, the output voltage, and the variable reference voltage.

Abstract: A direct current (DC) power supply, including a plurality of first printed circuit boards (PCBs) disposed on a primary side of the DC power supply, a plurality of alternating current (AC)/DC converter circuits having different potentials, each formed on a different one of the plurality of first PCBs, a second PCB disposed on a secondary side of the DC power supply, and a plurality of DC/DC converter circuits having an equal potential disposed on the second PCB. The AC/DC converter circuits are electrically connected in series and connected to an AC input of the DC power supply. The DC/DC converter circuits are electrically connected in parallel and connected to a DC output of the DC power supply.

Abstract: A first capacitor is connected between first and second power supply lines. A reactor is connected in series with the first power supply line or the second power supply line. A single-phase AC voltage is applied to a rectifying circuit. The rectifying circuit, which includes the first capacitor and the reactor, outputs a rectified voltage to the first and second power supply lines. A buffer circuit includes a second capacitor provided between the first and second power supply lines. The buffer circuit discharges the second capacitor at a controllable duty ratio. A booster circuit boosts the rectified voltage to charge the second capacitor. A DC current to be input to the booster circuit is reduced more as a voltage across the reactor is higher.

Abstract: Method for detecting an islanding condition of a grid connected energy conversion system and related DC/AC converter apparatus, adapted to optimize performance in terms of preservation of the power quality, provide synchronized perturbation for all the inverters of a plant, provide shut down capability within the time requested by utilities and safety standards and provide immunity to grid frequency fluctuations.

Abstract: A multi-level inverter having at least two banks, each bank containing a plurality of low voltage MOSFET transistors. A processor configured to switch the plurality of low voltage MOSFET transistors in each bank to switch at multiple times during each cycle.

Abstract: A flyback converter is provided with a synchronous rectifier (SR) controller including a pulse linear regulator (PLR) charging path and an LDO charging path. The SR controller is configured to monitor the switching period and/or duty cycle of a power switch in the flyback converter to select between the PLR and LDO charging paths.

Abstract: One embodiment includes a power supply system including a transformer comprising a primary, secondary, and auxiliary winding that are magnetically coupled. The system also includes a switch stage that generates a current through the primary winding in response to activation of a switch based on a control signal that is generated based on a feedback voltage associated with the auxiliary winding. The current can be induced in the secondary winding. The system also includes an output stage coupled to the secondary winding and that generates an output voltage based on the current induced in the secondary winding. The system further includes a feedback stage coupled to the auxiliary winding and comprising a discriminator configured to determine a zero-current condition associated with the current induced in the auxiliary winding based on monitoring a change in slope of the feedback voltage and to measure the feedback voltage during the zero-current condition.

Abstract: A method of operating a transformerless inverter connected on the input side to a generator and on the output side to a multiphase AC grid and comprising a multi-phase inverter bridge with a switch between a midpoint of a DC intermediate circuit on the input side and a terminal for a neutral conductor of the multiphase AC grid, includes feeding electric power from the DC intermediate circuit into the AC grid by the inverter bridge with the switch closed when first operating conditions are present, and opening the switch when there is a transition from the first operating conditions to second operating conditions different from the first operating conditions. The method further includes feeding electric power from the DC intermediate circuit into the AC grid by the inverter bridge with the switch open when the second operating conditions are present, and closing the switch when there is a transition from the second operating conditions to the first operating conditions.

Abstract: A switching power converter is configured to control switching noise by implementing a plurality of pulse width modulation modes of operation. The peak current in each pulse width modulation mode of operation is controlled so that an output power for the switching power converter is continuous with regard to transitions between the pulse width modulation modes.

Abstract: In a DC/DC converter, a driving method thereof, and a power supply using the same, the DC/DC converter includes a plurality of power switches connected as a serial string between an input terminal and a ground terminal, a first capacitor connected to at least two power switches of the serial string in parallel, an inductor connected between an intermediate node of the serial string and an output terminal, a second capacitor connected between the output terminal and the ground terminal, and a plurality of drivers configured to generate a switching control signal for each of the plurality of power switches. A voltage having no correlation with a voltage of the input terminal is supplied to a power terminal of each of the plurality of drivers.

Abstract: A current generation circuit including a first and a second bipolar transistors, a current distribution circuit that makes a first current and a second current flow through the first and second bipolar transistors, respectively, the first current and the second current corresponding to a first control voltage, a first NMOS transistor disposed between the first bipolar transistor and the first current distribution circuit, a second NMOS transistor disposed between the second bipolar transistor and the first current distribution circuit, a first resistive element, a first operational amplifier that outputs the second control voltage to the gates of the first and the second NMOS transistors according to a drain voltage of the first NMOS transistor and a reference bias voltage, and a second operational amplifier that generates the first control voltage according to a drain voltage of the second NMOS transistor and the reference bias voltage.

Abstract: A multi-level, step-up converter circuit includes an inductor including one terminal in communication with an input voltage supply. N transistor pairs are connected in series, where N is an integer greater than one. First and second transistors of a first pair of the N transistor pairs are connected together at a node. The node is in communication with another terminal of the inductor. Third and fourth transistors of a second pair of the N transistor pairs are connected to the first and second transistors, respectively. (N?1) capacitors have terminals connected between the N transistor pairs, respectively. An output capacitor has a terminal in communication with at least one transistor of the N transistor pair.