Abstract: A driver circuit for a PNP power transistor in an LDO regulator uses a Class AB (push-pull) buffer to supply the necessary base current to an NPN driver transistor, where the NPN driver transistor has its collector connected to the base of the PNP power transistor. A front end circuit of the driver, coupled to drive the Class AB buffer, uses a current diverting transistor, where a first portion of the current is used to control the pull-up transistor in the Class AB buffer, and the remainder of the current is used to control the pull-down transistor in the Class AB buffer, so the driver is very efficient. The portion of the driver circuit between the input of the driver circuit and the base of the NPN driver transistor is an inverting circuit. The driver can properly operate with an input voltage within two diode drops of ground.

Abstract: The present invention relates to a driver device (10) for driving a load (18), comprising input terminals (14, 16) for connecting the driver device (10) to a voltage supply (12) and for receiving an input voltage (V10) from the voltage supply (12), at least one output terminal for connecting the driver device (10) to the load (18), an electromagnetic converter unit (24) for converting a drive voltage to an output voltage (V20) for powering the load (18), two controllable switches (20, 22) connected to the input terminals (14, 16) for providing a variable voltage as the drive voltage to the electromagnetic converter unit (24), and a control unit (28) for controlling a first of the controllable switches (20, 22) on the basis of an electrical signal (V12) measured at a member of the electromagnetic converter unit (24) and a threshold level (40, 52) and for controlling a second of the controllable switches (20, 22) on the basis of a control parameter (50, tOFF) set to a value that the on-times of the controllable

Abstract: Systems and methods relate to a low-dropout voltage (LDO) voltage regulator which receives a maximum supply voltage and provides a regulated voltage to a load, where the load may be a processing core of a multi-core processing system. A leakage current supply source includes a leakage current sensor to determine a leakage current demand of the load of the LDO voltage regulator and a leakage current supply circuit to supply the leakage current demand. In this manner, the leakage current supply source provides current assistance to the LDO voltage regulator, such that the LDO voltage regulator can supply only dynamic current. Thus, headroom voltage of the LDO voltage regulator, which is a difference between the maximum supply voltage and the regulated voltage, can be reduced. Reducing the headroom voltage allows greater number of dynamic voltage and frequency scaling states of the load.

Abstract: A power conversion method of a power conversion device including a primary side port disposed in a primary side circuit and a secondary side port disposed in a secondary side circuit magnetically coupled to the primary side circuit with a transformer, the power conversion device adjusting transmission power transmitted between the primary side circuit and the secondary side circuit by changing a phase difference between switching of the primary side circuit and switching of the secondary side circuit, and changing a voltage of the secondary side port by a DC-DC converter connected to the secondary side port, the power conversion method including: monitoring a voltage ratio of a voltage of the primary side port and the voltage of the secondary side port; and causing the DC-DC converter to operate when the voltage ratio deviates from the reference value by the specified value or more.

Abstract: A step-down chopper type switching power-supply device includes a step-down chopper circuit including an inductor connected to a switching element connected to a DC power source, a regenerative-voltage detecting circuit, a control circuit controlling the switching element such that regenerative voltage becomes a reference voltage, an auxiliary power supply circuit charging a capacitor by using the regenerative voltage and supplying the voltage of the capacitor as power-supply voltage to the control circuit, and a activation circuit stopping supply of current to the capacitor after activation of the auxiliary power supply circuit, wherein, after activation of the auxiliary power supply circuit, in a case where voltage supplied from the DC power source is equal to or less than a first threshold value, the activation circuit performs control by the voltage supplied from the DC power source, such that current is supplied to the capacitor.

Abstract: The power supply apparatus for obtaining a direct current from an alternating voltage source includes a first DC/DC converter for outputting a first direct current and a second DC/DC converter for a second direct current lower than the first direct current from the first DC/DC converter, and the output voltage of the first DC/DC converter is changed to a lower direct current and the second DC/DC converter is driven in a continuously-conducting state.

Abstract: A buck-boost switching regulator has an output voltage boost circuit to provide a boosted output voltage. The boosted voltage is used to generate higher voltage control signals to gates of NMOS switches, resulting in an ability to operate at lower input voltages.

Abstract: A power conversion apparatus includes a first DC/DC converter which includes a first transformer, a first primary circuit provided at a primary side of the first transformer, and a first secondary circuit provided at a secondary side of the first transformer. The first secondary circuit includes sets of a switching element and a free-wheel diode, which is connected between an input terminal and an output terminal of the switching element, to perform synchronous rectification operation and diode rectification operation. The apparatus includes a second DC/DC converter which includes a second transformer, a second primary circuit provided at a primary side of the second transformer, and a second secondary circuit provided at a secondary side of the second transformer. The second secondary circuit includes a plurality of rectifier diodes, which are arranged in parallel with each other, to perform the diode rectification operation constantly.

Abstract: A common mode noise reduction apparatus includes a power converter that supplies electric power to a load; a housing that houses the power converter; a common mode inductor arranged between the power converter and the load; a power wire that passes through the common mode inductor and connects the power converter to the load; a grounding wire that passes through the common mode inductor and connects the housing and a bus of the power converter to ground potential on the load side; a first impedance element provided on the grounding wire between the load and the housing; and a second impedance element provided on the grounding wire between the bus of the power converter and the load.

Abstract: According to one embodiment, a voltage generation circuit includes a first boost circuit, a voltage division circuit, a first detection circuit, a capacitor and a first switch. The first boost circuit outputs a first voltage. The voltage division circuit divides the first voltage. The first detection circuit is configured to detect a first monitor voltage supplied to the first input terminal, based on a reference voltage which is supplied to a second input terminal of the first detection circuit, and to control an operation of the first boost circuit. The capacitor is connected between an output terminal of the first boost circuit and the first input terminal of the first detection circuit. The first switch cuts off a connection between the capacitor and the first detection circuit, based on an output signal of the first detection circuit, until the first voltage is output from the first boost circuit.

Abstract: A switching regulator including an output switch element; a rectification switch element; an oscillation circuit; an error amplifier circuit; a slope circuit; a first voltage comparison circuit; a second voltage comparison circuit; a one pulse generation circuit; a control circuit; and a backflow detection circuit, and a control method thereof suppress variations to be stabilized with respect to a target value of the load current for switching between a PWM control and a PFM control, and ensure the switching from the PFM control to the PWM control or from the PWM control to the PFM control even if various parameters including external elements such as chips, coils, and capacitors vary.

Abstract: Described examples include controllers and methods for controlling an inverter to drive a load and for detecting load faults by determining phasor values representing voltages and currents associated with the individual load phases based on sets of input values, determining voltage and current sequence components according to the phasor values, determining a sequence impedance value by recursively solving a set of update equations at least partially according to the voltage and current sequence components, and detecting a load fault when the sequence impedance value exceeds a threshold value.

Abstract: Methods and apparatus are presented for sampling low side inverter phase currents, in which current sampling is selectively delayed in a given PWM cycle by a non-zero sampling delay time value from a nominal sample time if the middle pulse width value is less than a non-zero first threshold to facilitate adequate signal settling for accurate current measurement, and if a middle total continuous on-time near the end of the given PWM cycle is less than a non-zero second threshold, the middle total continuous on-time is selectively extended by adding a non-zero adjustment offset time value to a middle pulse width value for a next PWM cycle.

Abstract: An apparatus includes a voltage regulation module that controls output voltage of a bidirectional DC to DC converter to an output voltage reference over an output current range between a positive power reference and a negative power reference. A positive power regulation module controls output power of the converter to the positive power reference over a positive constant power range between the output voltage reference and a positive output current reference. A negative power regulation module controls output power of the converter to the negative power reference over a constant power range between the output voltage reference and a maximum negative power limit, and a constant current module limits output current to a positive output current reference in a range between a minimum output voltage and output power of the converter reaching the positive power reference.

Abstract: An integrated circuit chip includes a first input port, a first output port, and first and second transistors electrically coupled in series across the first input port. The second transistor is also electrically coupled across the first output port and is adapted to provide a path for current flowing through the first output port when the first transistor is in its non-conductive state. The integrated circuit chip additionally includes first driver circuitry for driving gates of the first and second transistors to cause the transistors to switch between their conductive and non-conductive states. The integrated circuit chip further includes first controller circuitry for controlling the first driver circuitry such that the first and second transistors switch between their conductive and non-conductive states to at least substantially maximize an amount of electric power extracted from an electric power source electrically coupled to the first input port.

Abstract: System controller and method for protecting a power converter. The system controller includes a first controller terminal configured to output a drive signal to a switch to affect a first current flowing through a primary winding of a power converter. The power converter further includes a secondary winding coupled to the primary winding, and the drive signal is associated with one or more switching periods. Additionally, the system controller includes a second controller terminal configured to receive a sensing voltage from a sensing resistor. The sensing voltage represents a magnitude of the first current flowing through the primary winding of the power converter. The system controller is configured to process information associated with the sensing voltage and a reference voltage, and determine whether an average output current of the power converter is larger than a current threshold.

Abstract: A reversible matrix converter circuit is provided with n levels per phase including n conversion arms exhibiting on one side n ends for generating or receiving respectively n intermediate DC voltage levels, and exhibiting on another side n ends linked at a common point of AC signal input or output. The circuit includes: —two external arms linked respectively to the highest level of positive voltage and to the lowest level of negative voltage, these two external arms each having a single IGBT transistor or two power transistors, linked by their emitter, —two IGBT power transistors, linked in series by their emitter on each of the n?1 internal arms, —filtering capacitors disposed respectively between the n intermediate voltage levels.

Abstract: Aspects of the disclosure provide a circuit that includes a controller. The controller is configured to receive a signal indicative of a current flowing in a magnetic component and control a switch in connection with the magnetic component to shape a peak current of the current flowing in the magnetic component. The controller shapes the peak current from a first peak current level to a second peak current level in order to reduce an amplitude of a ripple in a current drawn from a triode for alternating current (TRIAC) during a time to satisfy a holding current requirement of the TRIAC.

Abstract: A method for start control of photovoltaic inverter, a system thereof, and a photovoltaic power generation system are provided. A fan of the photovoltaic inverter is controlled to operate in a case that input voltage of the photovoltaic inverter is greater than a start threshold, and the fan operation is used as a load. Input voltage drop before and after the fan operates is obtained, and in a case that the input voltage drop is less than or equal to a voltage determination threshold, the photovoltaic inverter is controlled to start a grid connection. The voltage determination threshold is changed based on a power determination threshold of the photovoltaic inverter.

Abstract: A low power bandgap circuit device that generates temperature independent reference voltages and/or zero temperature coefficient currents is disclosed. The circuit comprises a first pair of transistors, an amplifier, a star connected resistive network, and a second pair of transistors, wherein zero temperature coefficient currents are generated through mirroring and reuse of current from the star connected resistive network.