Abstract: A multi-phase DC-DC power converter is provided, which includes a pulse width modulation (PWM) controller and a plurality of output stage circuits. The plurality of output stage circuits converts an input voltage into an output voltage. The PWM controller includes a feedback circuit and a PWM generation module. The feedback circuit outputs a trigger signal according to the output voltage and a ramp signal. The PWM generation module at least generates a first PWM signal and a second PWM signal. In addition, a waveform of the first PWM signal partially overlaps a waveform of the second PWM signal at a logic high level.

Abstract: Provided is a converter control device which detects an on-failure of an auxiliary switch constituting an auxiliary circuit of a soft switching converter and can prevent element failures. A current sensor for detecting the current flowing in a coil is provided between a fuel cell and the. A controller sequentially detects current by use of the current sensor and makes a judgment as to whether or not the detected current has exceeded an overcurrent threshold value stored in a memory (not shown). When the controller judges that the current has exceeded the overcurrent threshold value, the controller judges that a second switching element has an on-failure, and performs a fail-safe operation by stopping the driving of a converter (for example, a U-phase converter) of an auxiliary circuit provided with this second switching element.

Abstract: A control method for a power supply system having at least two power parts with power outputs connected in parallel, wherein each power part is actuated via a separate control and where at least one first power limit is specified for each control, where the control actuates the allocated power part up to the first power limit in a normal mode, a first drawdown value of the output voltage is specified for each control upon reaching the first power limit, and the respective control regulates the output voltage of the related power part to the first drawdown value upon reaching the first power limit so that the parallel connection of a plurality of power parts without a super-ordinate control is achieved.

Abstract: In one embodiment, a control circuit configured for an interleaved switching power supply, can include: (i) a feedback compensation signal generation circuit configured to sample an output voltage of the interleaved switching power supply, and to generate a feedback compensation signal; (ii) a first switch control circuit configured to compare a voltage signal indicative of an inductor current in the first voltage regulation circuit against the feedback compensation signal, and to control a first main power switch in the first voltage regulation circuit; and (iii) a second switch control circuit configured to turn on a second main power switch in the second voltage regulation circuit after half of a switching cycle after the first main power switch is turned on, and to regulate an on time of the second main power switch.

Abstract: Disclosed is a low drop-out voltage regulator circuit with a distributed output network coupled to a pixel array for use in image sensor circuitry. The regulator circuit comprises voltage regulating circuitry and a distributed output network, wherein the distributed output network comprises drive transistors disposed along and connected between a supply track and an output track. The spatial distribution of the drive transistors improves heat dissipation within the regulator circuit, and a combination of low current flow and regulated output voltage reduces IR drop across the output track. The improved heat dissipation increases device lifespan and performance, whereas the reduction in IR drop across the output track provides better pixel response, readout uniformity, and image quality.

Abstract: Each of master and slave switching power supply apparatuses (2m, 2s) has an IGBT (10m or 10s) switching-controlled by a PWM pulse signal produced, based on a clock signal, by a switching device driving PWM pulse output section (28m or 28s), to thereby provide DC power in parallel to a load (5). The clock signal produced in the master switching power supply apparatus (2m) is coupled to the slave switching power supply apparatus (2s) through a photocoupler (36m) in the master switching power supply apparatus (2m) and a photocoupler (38s) of the slave switching power supply apparatus (2s). Also, the clock signal developed at the output of the photocoupler (36m) is coupled through a photocoupler (38m) to the master switching power supply apparatus (2m). The photocouplers (36m, 38m, 38s) have the same delay characteristic.

Abstract: The present invention discloses an adaptive phase-shifted synchronization clock generation circuit and a method for generating phase-shifted synchronization clock. The adaptive phase-shifted synchronization clock generation circuit includes: a current source generating a current which flows through a node to generate a node voltage on the node; a reverse-proportional voltage generator coupled to the node for generating a voltage which is reverse-proportional to the node voltage; a ramp generator receiving a synchronization input signal and generating a ramp signal; a comparator comparing the reverse-proportional voltage to the ramp signal; and a pulse generator for generating a clock signal according to an output from the comparator.

Abstract: An embodiment of a driving device is proposed for supplying at least one regulated global output current to a load. The driving device includes programming means for programming a value of the global output current within a global current range. Reference means are provided for supplying a reference voltage, which has a value corresponding to the value of the global output current. Conversion means are then used for converting the reference voltage into the global output current. The conversion means may further include a plurality of conversion units for corresponding partial current ranges, which partition the global current range.

Abstract: According to example configurations herein, a controller receives a value indicative of a number of phases in a power supply to be activated for producing an output voltage to power a load. A resonant frequency of the power supply changes depending on the number of phases activated. According to one configuration, a controller utilizes the value to proportionally adjust at least one control parameter associated with the power supply in accordance with a change in the resonant frequency. In addition to modifying a parameter based on the number of activated phases and/or the resonant frequency of the power supply, the controller can also use the value of the input voltage as a basis to adjust at least one control parameter. Moreover, according to one example configuration, the controller digitally computes values for the at least one control parameter based on a number of phases to be activated.

Abstract: The respective main electrodes of the semiconductor switching elements such as IGBTs, which are respectively mounted on the plurality of insulating boards, are electrically connected to each other via the conductor member. This configuration makes it possible to suppress the occurrence of the resonant voltage due to the junction capacity and the parasitic inductance of each semiconductor switching element.

Abstract: A multi-phase DC-DC converter and a controlling method thereof are provided. The multi-phase DC-DC converter includes a plurality of output units, a sensing unit, and a pulse width modulation (PWM) controller. Each of the output units is coupled to one corresponding output inductance of a plurality of output inductances, and each of the output units and the corresponding output inductance have a phase node therebetween. The sensing unit is coupled to the phase nodes to acquire output currents of all phases and provide a plurality of difference voltages that respectively represent current differences of the phases, wherein a value of each of the difference voltages is not zero. The PWM controller adjusts a duty cycle of a PWM signal of the corresponding output unit according to each difference voltage.

Abstract: A power supply system includes a control unit comprising a detecting and converting unit that is operable to generate a detected current based on a difference between a set voltage and a voltage representative of a current flow through an energy storage member.

Abstract: There is provided a DC-DC converter which converts an input voltage into an output voltage for supply to a load, in which an input terminal receives the input voltage, an output terminal outputs the output voltage, power stages each includes: a high side switch, a low side switch and an inductor, the control unit executes a first mode and a second mode wherein the first mode controls the high side switch and the low side switch in each of the power stages so that a ratio of an output current in each of the power stages to a load current flowing through the load becomes a set value and the second mode controls the high side switch and the low side switch in each of the power stages so that duty ratios of the high side switch and the low side switch are equalized among the power stages.

Abstract: Systems and methods are provided that may be implemented to dynamically manage voltage regulator switching frequency. In one embodiment, the disclosed systems and methods may be implemented to dynamically find the optimal voltage regulator switching frequency based on the load current (IOUT) and efficiency in a switching voltage regulator device (VR), such as a voltage regulator down device (VRD) that is embedded on a system board of an information handling system.

Abstract: A DC power stage provides a power output that tracks a PCM signal input. A mapping unit generates an integer number of N digital PWM signals each switched at a same switching frequency by switching states of the PWM signals one at a time based on a level of the PCM signal input. An imbalance correction unit adjusts a duty ratio of the PWM signals relative to one another based on differentially accumulating errors among the PWM signals to prevent divergence of PWM signals. N corresponding switches therefrom switch power from a DC power source. N inductances in parallel produce a combined signal that is low pass filtered to provide the power output. Switching is between only those state combinations where the switching frequency is cancelled in the combined signal. The switching frequency is a sampling frequency of the PCM signal input divided by a product of 2 times N.

Abstract: Techniques for optimizing the trade-off between minimizing switching losses and minimizing conduction losses in a buck converter. In an aspect, each of a high-side switch and a low-side switch may be implemented as a plurality of parallel-coupled transistors, each transistor having an independently controllable gate voltage, allowing adjustment of the effective transistor size. In response to the target voltage of the buck converter corresponding to a relatively high voltage range, more high-side switch transistors and fewer low-side switch transistors may be selected. Similarly, in response to the target voltage corresponding to a relatively low voltage range, more low-side switch transistors and fewer high-side switch transistors may be selected. In an aspect, the techniques may be applied during a pulse-frequency modulation mode.

Abstract: A multiphase DC-to-DC converter is disclosed herein, which includes at least one DC-to-DC converting module. Each DC-to-DC converting module at least includes a first output inductor, a second output inductor and a current detector. The current detector is configured for detecting currents pass through the first output inductor and second output inductor. The current detector includes a first resistance, a second resistance, a first capacitor, a second capacitor, and a third resistance. The third resistance is directly or indirectly coupled between the first capacitor and a load circuit, and directly or indirectly coupled between the second capacitor and the load circuit, such that when the first capacitor is charged, a portion of the current charging the first capacitor passes through the second capacitor.

Abstract: The present document relates to the control of high side switches, e.g. the high side switches of half bridges. In particular, the present document relates to an efficient control circuit for controlling a plurality of high side switches. A control circuit for controlling a plurality of parallel high side switches of a respective plurality of parallel bridges is described. The control circuit comprises a charge provisioning unit configured to provide an electrical charge. Furthermore, the control circuit comprises a plurality of sets of high control switches for the plurality of high side switches, respectively; wherein each set of high control switches is configured to arrange the charge provisioning unit in parallel to a gate-source capacitance of the respective high side switch.

Abstract: A switching voltage regulator including a comparison module configured to receive a reference voltage and a feedback voltage and to generate a comparison signal corresponding to a difference between the reference voltage and the feedback voltage, an offset module configured to generate an offset signal based on a number of active phases of the voltage regulator, an adder configured to generate a control signal based on the comparison signal and the offset signal, a plurality of pulse-width-modulated (PWM) power stages, and a control module configured to control the plurality of PWM power stages based at least in part on the control signal generated by the adder.

Abstract: Systems and methods are provided for regulating the state of charge of a battery. An exemplary electrical system includes a fuel cell coupled to a bus and a battery coupled to the bus via a switching arrangement coupled to a capacitor. An exemplary method for operating the electrical system involves operating the switching arrangement such that a voltage of the battery is substantially equal to a voltage of the fuel cell when a state of charge of the battery is greater than a lower threshold value and less than an upper threshold value, and operating the switching arrangement to couple the capacitor electrically in series between the battery and the bus when the state of charge of the battery is not between the lower threshold value and the upper threshold value.

Abstract: A switching regulator arrangement utilizes internal capacitors rather than external capacitors for driving output power transistors. Low-dropout linear voltage regulators together with a dip compensation circuit provide an intermediate supply voltage for driving power transistors under circumstances in which a supply voltage is greater than a gate drive voltage of the power transistor, allowing for a more efficient absorption of transient current.

Abstract: A boost converter circuit includes a first boost module, a first detecting unit, a second boost module and a first detecting unit. The first boost module includes a first comparing control unit. The first detecting unit is coupled to the first boost module, and the first detecting unit adjusts a first input signal of the first comparing control unit according to a first signal of the first boost module. A second boost module is connected in parallel to the first boost module, and the second boost module includes a second comparing control unit. The second detecting unit is coupled to the second boost module, and the first detecting unit adjusts a second input signal of the second comparing control unit according to a second signal of the second boost module.

Abstract: Consistent with an example embodiment, there is a current control circuit for controlling current flow between a first terminal and second terminal. The current control circuit comprises a current-sensing power MOSFET (metal-oxide semiconductor field effect transistor). Current control is useful for limiting current flow during linear mode operations such as “hotswap”, “soft start” and “eFuse” operations, in particular, the reducing of or the preventing of high current surges due to discharged capacitive loads suddenly being switched into circuit. Such current surges can cause supply interference or cause malfunction of sensitive circuits due to the effects of the noise pulse. In extreme cases, fuses may blow or circuit breakers may trip due to the high current surges, therefore taking one or more systems offline.

Abstract: An embodiment of a power supply includes an input node operable to receive an input voltage, an output node operable to provide a regulated output voltage, an odd number of magnetically coupled phase paths each coupled between the input and output nodes, and a first magnetically uncoupled phase path coupled between the input and output nodes. Such a power supply may improve its efficiency by activating different combinations of the coupled and uncoupled phase paths depending on the load conditions. For example, the power supply may activate only an uncoupled phase path during light-load conditions, may activate only coupled phase paths during moderate-load conditions, and may activate both coupled and uncoupled phase paths during heavy-load conditions and during a step-up load transient.

Abstract: An uninterruptible power supply (UPS) includes a rectifier, a buck converter, a solar energy module, a boost converter, a controller, and a power distribution unit (PDU). The solar energy module receives solar energy and converts the solar energy to a first DC voltage. The controller compares the first DC voltage with a preset voltage, and outputs a control signal to turn the boost converter on or off. When the boost converter is turned off, the rectifier receives an AC voltage from the AC power source and converts this to a rectified DC voltage which is output to the buck converter. When the boost converter is turned on, the boost converter converts the first DC voltage to a second DC voltage. The buck converter converts the rectified DC voltage or the first DC voltage to a working DC voltage and outputs to a power supply unit through the PDU.

Abstract: The present invention discloses a current balance circuit for a multiphase DC-DC converter. The current balance circuit comprises a current error calculation circuit, for generating a plurality of current balance signals indicating imbalance levels of a plurality of inductor currents of a plurality of channels of the multiphase DC-DC converter according to a plurality of current sensing signals of the plurality of channels, a time shift circuit, for adjusting pulse widths of a plurality of clock signals according to the plurality of current balance signals, and a ramp generator, for deciding shift levels of a plurality of ramp signals according to the plurality of clock signals.

Abstract: A master transistor and a slave transistor are both insulated gate bipolar transistors. A slave diode is connected in anti-parallel to the slave transistor. The master transistor is brought into conduction if a current flowing in a master reactor becomes zero, and is brought into nonconduction after elapse of a first period. The slave transistor is brought into conduction subject to elapse of a certain period after the master transistor is brought into conduction that is one of conditions for conduction of the slave transistor, and is brought into nonconduction after elapse of a second period shorter than the first period. The certain period is shorter than a period from when the master transistor is brought into conduction until when the master transistor is brought into conduction again.

Abstract: A power supply unit comprises at least one first converter unit and a second converter unit. The at least one first converter unit is controlled with a first controller and supplies at a first output at least one of a first output voltage that is regulated using a first voltage regulator and an output current that is regulated using a first current regulator. The second converter unit is controlled by a second controller and supplies at a second output at least one of an output voltage that is regulated using the second voltage regulator and an output current that is regulated using a second current regulator. The first and second outputs are connected in parallel for providing a higher output power, and at least one controller includes a supervision unit for recognizing an output-side parallel connection.

Abstract: A buck switching regulator includes a feedback control circuit including a balanced feedback network including first and second gain circuits configured to generate first and second feedback signals, respectively, indicative of the regulated output voltage; a ripple generation circuit configured to inject a first ripple signal to the first gain circuit and a second ripple signal to the second gain circuit; an operational transconductance amplifier (OTA) configured to receive the second feedback signal and a reference signal and to generate an output signal being coupled to a node in the feedback control circuit; and a comparator configured to receive the first feedback signal and a comparator reference signal and to generate a comparator output signal. The output signal of the OTA is applied to the feedback control circuit to cancel a voltage offset in the regulated output voltage due to the injected ripple signal to the first gain circuit.

Abstract: A power system for providing an output current at a regulated system output voltage includes a first power stage and a second power stage, each being a constant on-time (COT) controlled power converter. The first and second power stages generate respective first and second regulated output voltage having reduced or very small output ripple at a common output voltage node. The first and second power stages each includes a ripple injection circuit to inject a ripple signal to the feedback control circuit in each power stage. The power system further includes a current sharing control circuit configured to measure a first output current of the first power stage and a second output current of the second power stage, and to generate a control signal to modulate the feedback control circuit of the second power stage to force the second output current to equal to the first output current.

Abstract: A high precision DC/DC resonant converter with a wide load range includes a first switch leg having one end connected to an anode terminal of a DC power source and the other connected to a cathode terminal of the DC power source to independently operate at a switching frequency used in an application of an output voltage for no load or a light load equal to or less than a rated load; and one or more second switch legs having one end connected to the anode terminal of the DC power source and the other end connected to the cathode terminal of the DC power source to operate at a switching frequency for the rated load or a frequency equal to or less than the switching frequency used in the application of the output voltage for no load or the light load that the first switch leg takes charge of.

Abstract: A power factor correction circuit is provided which may include a first switched-mode converter circuit comprising a first inductor, at least one second switched-mode converter circuit having a second inductor, a control circuit coupled to the first and second switched-mode converter circuits, wherein the control circuit is configured to start a switching pulse for the second switched-mode converter circuit when the following conditions are fulfilled: the second inductor of the second switched-mode converter circuit has a predefined magnetization state and a predefined time period has elapsed since the start of a switching pulse for the first switched-mode converter circuit, wherein the predefined time period is a predefined fraction of the time period from the start of a previous switching pulse for the second switched-mode converter circuit to a time when the second inductor of the second switched-mode converter circuit has the predefined magnetization state.

Abstract: A regulated, power supply system is described using multiphase DC-DC converters with dynamic fast-turnon, slow-turnoff phase shedding, early phase turn-on, and both load-voltage and drive-transistor feedback to pulsewidth modulators to provide fast response to load transients. In an embodiment, a system master can automatically determine whether all, or only some, slave phase units are fully populated. The programmable system includes fault detection with current and voltage sensing, telemetry capability, and automatic shutdown capability. In an embodiment, these are buck-type converters with or without coupled inductors, however some of the embodiments illustrated include boost configurations.

Abstract: The Application is directed at arrangements at which switch mode power converters share a common load. More particularly, the application provides a masterless arrangement in which no single converter controls the operation of the other converters. This is achieved by an arrangement in which each converter attempts to share its current measurement with other converters through an arbitration scheme employed on a data line, with the winning converter providing a defacto current measurement; for example, a maximum or minimum, to the overall arrangement.

Abstract: An integrated circuit device for delivering power to a load includes a controller circuit, a cascade circuit, and a power delivery circuit. The controller circuit generates a plurality of control signals. The cascade circuit receives the control signals from the controller circuit and sequentially outputs the control signals onto a cascade bus. The power delivery circuit receives the control signals from the controller circuit and delivers an amount of current to the load, in response to one of the control signals.

Abstract: A switching regulator includes a multiphase converter which includes a plurality of main phases configured to covert a power supply voltage to a lower voltage for application to an electronic device at different load conditions. The switching regulator also includes an auxiliary phase configured to operate in a pulse frequency modulation mode during a light load condition so that power is supplied to the electronic device by at least the auxiliary phase during the light load condition.

Abstract: A multi-phase non-inverting buck boost voltage converter has a plurality of buck boost voltage regulators. Each regulator is associated with a separate phase for generating a regulated output voltage responsive to an input voltage. A plurality of current sensors are each associated with one of the plurality of buck boost voltage regulators for monitoring an input current to the associated buck boost voltage regulator and generating a current sense signal for the associated phase. A plurality of buck boost mode control circuitries are each associated with one of the buck boost regulator for controlling an associated buck boost voltage regulator using peak current mode control in a buck mode of operation and valley current mode control in boost mode of operation responsive to a common error voltage and the associated current sense signal. The plurality of buck boost mode control circuitries provides current balancing between the phases.

Abstract: A thermal balance conversion circuit includes a voltage conversion circuit, a temperature detection circuit, a PWM controller, and a signal integration controller. The voltage conversion circuit includes a plurality of voltage conversion units, and each of the voltage conversion units converts the DC voltage of a external power to a driving voltage. The temperature detection circuit includes a plurality of temperature detection units, and the plurality of temperature detection units detects temperatures of the plurality of voltage conversion units. The pulse width modulation controller outputs a plurality of different phase PWM signals according to each of the voltage conversion units. The signal integrated controller receives the PWM signals from the PWM controller to control the voltage conversion of each of the voltage conversion unit.

Abstract: A mode controller shifts, along with increase in an electric power in first and second of chopper circuits and, operation modes of the first and the second of the chopper circuits from a first mode to a third mode via a second mode. An operation controller causes, in the first mode, the first of chopper circuit to perform an chopping operation, and the second of chopper circuit to suspend the chopping operation, in the second mode, causes the first and the second of chopper circuits to alternatively perform the chopping operations, and in the third mode causes both of the first and the second of chopper circuits to perform the chopping operations.

Abstract: A multi-phase power block for a switching regulator includes a phase control circuit, N power cells and a current sharing control circuit. The phase control circuit is configured to receive a single phase PWM clock signal and generate N clock signals in N phases. Each of the N power cells includes a pair of power switches, gate drivers, a control circuit receiving one of the N clock signals and generating gate drive signals for the gate drivers, and an inductor. The current sharing control circuit is configured to assess the inductor current at the inductor of the N power cells and to generate duty cycle control signals for the N power cells. The duty cycle control signals are applied to the control circuits to adjust the duty cycle of one or more clock signals supplied to the power cells to balance a current loading among the N power cells.

Abstract: A continuous power supply system suitable for input connection to N continuous power supply networks that are distinct and connected to a single ground potential, where N is an integer greater than or equal to 2. Said continuous power supply system comprises means for switching/selecting one of the power supply networks, means for regulating an output voltage established by the power supply system, and a control unit for the means for switching/selecting and for the means for regulating. The means for regulating the output voltage includes N distinct buck-boost converters with shared inductance. A given buck-boost converter is dedicated to each power supply network for regulating the voltage output of the power supply system on the basis of an input voltage established by the corresponding power supply network.

Abstract: A switching transistor is configured such that its on resistance RON is switchable between at least two values RON1 and RON2. When the switching transistor is switched from off to on, a control circuit sets the on resistance of the switching transistor to the first value RON1 for a first period immediately after the switching of the switching transistor. Subsequently, for a second period until the switching transistor is turned off, the control circuit sets the on resistance of the switching transistor to the second value RON2 that is smaller than the first value RON1.

Abstract: There is provided a power factor correction circuit including: a main switching unit including a first main switch and a second main switch performing a switching operation to regulate a phase difference between a current and a voltage of input power, respectively; a main inductor unit including a first main inductor and a second main inductor accumulating or discharging energy according to a switching operation of each of the first main switch and the second main switch; a snubber switching unit including a first snubber switch and a second snubber switch providing zero-voltage turn-on conditions to the first main switch and the second main switch, respectively; and a controller controlling a switching operation of the main switching unit and the snubber switching unit.

Abstract: A switching power supply circuit has a controller, a power switch, and an inductor circuit that is coupled to a power node of the power switch and to a capacitor. The inductor circuit has several discrete component conductors that are connected to each other in parallel and laid out side-by-side and wired such that each of the inductors is oriented with opposite polarity relative to another adjacent one of the inductors. Each inductor has associated first and second traces that are used to wire it to the power node and the capacitor. These traces for one inductor have matched characteristics with those of an adjacent inductor. Other embodiments are also described and claimed.

Abstract: Various embodiments of the invention provide extend the switching frequency range of DC/DC multiphase switching regulators in order to overcome prior art frequency limitations in the number of available phases, for example, in low input to output ratio applications. In certain embodiments, this is accomplished by enabling partial overlap between multiple phases using asynchronous logic. The invention is easily scalable without introducing significant silicon area penalties.

Abstract: A DC-DC converter has a plurality of DC-DC converting units, a plurality of inductor elements, a plurality of duty detection circuits, and a duty adjustment circuit configured to compare output signals from two detection circuits as each group, and to adjust the duty ratio of the DC-DC converting unit connected to one of the two duty detection circuits based on a result of comparing the output signals so that the duty ratio of the square wave voltage of each group becomes equal.

Abstract: A circuit for providing at least two power supply voltages from a D.C. voltage provided by a first switched-mode converter between a first and a second terminals, wherein: a second reversible buck-type switched-mode converter is powered with said D.C. voltage; a capacitive dividing bridge connects said first and second terminals, the midpoint of the capacitive dividing bridge corresponding to the output of the second converter and defining a third terminal of provision of an intermediary potential; and said two power supply voltages are respectively sampled between the first and third and between the third and second terminals.

Abstract: An IC provides tracking between multiple regulated voltages. The IC includes, a voltage reference circuit, a voltage multiplier circuit, and first and second voltage regulator circuits. The voltage reference circuit generates a first reference voltage. The first voltage regulator circuit generates, at a first terminal of a first output transistor, a first regulated voltage that is based on the first reference voltage. The voltage multiplier circuit generates a second reference voltage from an equivalent of the first reference voltage. The second voltage regulator circuit generates, at a first terminal of a second output transistor, a second regulated voltage that is based on the second reference voltage. At least one terminal of the second output transistor is capacitively coupled to the first terminal of the first output transistor.

Abstract: A step-down switching regulator includes a switching element performing switching in accordance with an input control signal to charge an inductor with an input voltage; a synchronous rectification element performing switching in accordance with an input control signal to discharge the inductor; a power supply circuit part generating and outputting a supply voltage; a capacitor connected to the connection of the switching element and the inductor; a first drive circuit part controlling the switching of the switching element in accordance with an input control signal; a second drive circuit part controlling the switching of the synchronous rectification element in accordance with another input control signal; and a control circuit part generating and outputting the control signals to the first and second drive circuit parts so that the predetermined constant voltage is output from an output terminal, wherein the second drive circuit part is supplied with power from the capacitor.

Abstract: A switching device is disclosed in which electric current through a rectification circuit, depending on whether a main switching element turns on or off, and thus electric current from the rectification circuit flows through whichever of first and second sub-switching elements, turns on. By controlling the turning on and off of the first and second sub-switching elements, the switching is performed which determines through which of the first and second output circuits the electric current from the rectification circuit flows. Thus, a voltage that is a result of transforming a voltage from a DC power supply in response to the electric current flowing through the first output circuit, is output from a first output terminal, and a voltage that is a result of transforming a voltage from the DC power supply in response to the electric current flowing through the second output circuit, is output from a second output terminal.