Abstract: In one embodiment, a startup circuit for a power supply is provided. The startup circuit comprises a resistance coupled between a voltage source and a first node. A first capacitor, coupled to the first node, is operable to be charged by current flowing through the resistance. A first transistor has an emitter, a base, and collector, wherein the collector is coupled to the voltage source and the base is coupled to the first node. A diac circuit, coupled to the emitter of the first transistor, is operable to fire to turn on the first transistor, thereby allowing discharge of the first capacitor through the base-emitter junction of the first transistor. A second capacitor is operable to be charged by current related to a discharge voltage resulting from the firing of the diac circuit. The second capacitor operable to store charge to provide VCC voltage to a controller of the power supply.

Abstract: Power gating control and related circuitry for integrated circuits is described herein. A centralized power gating control circuit uses trigger circuits to control the on/off switching of power gating circuits distributed at different points in a chip, integrated circuit, module or block (collectively “IC”). The power gating circuits may include power gates partitioned for sleep and shutdown modes. The shutdown mode power gates may employ multi-level power gate architecture to minimize inrush current during power-up of the IC. Each level may be associated with or tied to a trigger circuit and activated based on a voltage level reaching the voltage threshold of the trigger circuit. The power gating control and related circuitry may be embedded in the IC.

Abstract: A switching power supply has a function of improving a power factor, and outputs insulated DC. The switching power supply performs two kinds of controls for switching devices exclusive to each other: controlling of a switching device provided in a direction in which the discharging of a primary-side smoothing capacitor is prohibited at the time of suspension of commercially available AC power and near the zero cross of an input voltage; and causing a switching device provided between the output side of a third winding and the primary-side smoothing capacitor to control a charging current, thereby charging a capacitor in a boosted manner.

Abstract: The present invention provides an isolated switch-mode power supply device capable of sufficiently reducing power consumption in a standby mode. An isolated switch-mode power supply device includes: a capacitor that supplies control power for controlling switching of a switching element; a first control unit that includes a constant current supplying unit that controls switching of the switching element; a switching element that connects or disconnects the first control unit and the capacitor; a capacitance element unit having a capacitor to which a constant current is supplied from the constant current supplying unit, a capacitor charge voltage of the capacitance element unit changing according to an outputted voltage in the standby mode; and a second control unit that controls power supply to the first control unit by closing or opening the switching element during a switching pause period in the standby mode according to the capacitor charge voltage of the capacitor.

Abstract: A voltage regulator permits reduced current consumption by promptly and timely stopping the operation of an inrush current protection circuit immediately after the voltage regulator is started up. The voltage regulator has an output voltage detection circuit, which issues a detection signal to actuate the inrush current protection circuit when a low voltage at an output terminal is detected at the time of starting up the voltage regulator. When it is detected that the voltage at the output terminal has reached a predetermined level, the operation of the inrush current protection circuit is stopped and a power path of the output voltage detection circuit is cut off.

Abstract: A voltage regulator is capable of continuously and smoothly preventing an inrush current independently of a startup characteristic of a reference voltage circuit. The voltage regulator is provided with an inrush current protection circuit composed of a constant-current circuit, a first transistor having the source thereof connected to the constant-current circuit and the gate thereof controlled by an output voltage detection circuit, a capacitor connected between the first transistor and the gate of an output transistor, a second transistor having the gate thereof connected to the drain of the first transistor and the source thereof connected to a power supply terminal, and a third transistor, which is connected between the second transistor and the output transistor and the gate of which is controlled by the output voltage detection circuit.

Abstract: The invention discloses a power gating for in-rush current mitigation. Firstly the circuit uses small power switch cells at first stage, such that those power switch cells run in saturation region. Secondly a delay unit delays a switch signal to control the dwell time of current to reduce the peak value of the current. Thirdly large power switch cells are used at the rest, such that those power switch cells operate in linear region.

Abstract: A low-power, low-latency power-gate (LPLLPG) circuit is used to shut off or otherwise reduce power that is provided to electronic component(s), such as in a sleep or standby mode. ON-rush current is controlled by sizing at least one transistor in the power-gate circuit, and power consumption of the power-gate circuit in both standby state and active state is reduced by not using additional delay elements. Ramping up a gated voltage supply with low ON-rush current is performed by applying/using logic rather than delay signals. This logic does not turn ON transistors in the power-gate circuit until the gated voltage supply has ramped up close to a level of an ungated voltage supply. By not using additional delay cells, faster turn OFF of the gated voltage supply is obtained.

Abstract: An AC-DC power converter has a phase-shifting autotransformer based rectifiers and DC capacitors. Soft start of the AC-DC power converter is achieved by designing the autotransformer to operate at a low peak flux density at a point of AC voltage step application (initial turn on). The addition of a controlled impedance segregates capacitor charging from the initial magnetizing process of the autotransformer.

Abstract: A power converter, comprising an input circuit having a single diode rectifier (D); and a switcher mode power supply IC (SMPS).

Abstract: A power isolation system and method is disclosed. The system includes a transformer suitable for use in the power isolation system, and a semiconductor device electrically connected to the transformer to provide a reduction of the inrush current associated with powering the transformer, wherein the semiconductor device is activated upon power up based upon the previous shutdown state of the power isolation system to provide a soft start to the transformer, and after activation of the transformer, the semiconductor device is shorted in the system.

Abstract: To provide a time constant circuit and the like capable of acquiring a characteristic of an output voltage that attenuates gradually after attenuating steeply, compared to a characteristic that attenuates monotonously. The time constant circuit includes: a series/parallel circuit formed by serially connecting a plurality of parallel circuits each formed with a resistance element and a capacitance element between a first terminal and a second terminal; and a voltage-dividing resistance element connected between a third terminal connected to the second terminal and a fourth terminal. A first parallel circuit is formed with a first resistance element and a first capacitance element, a second parallel circuit with a second resistance element and a second capacitance element, and an n-th parallel circuit with an n-th resistance element and an n-th capacitance element. Note that “n” is the number of the parallel circuits and it is an integer of 2 or larger.

Abstract: A circuit arrangement includes a switching element that switches a load current, a current-limiting element connected in series to the switching element, a bistable first relay connected in parallel to the switching element and the current-limiting element, and a control circuit that switches the power-supply unit from a first operating state to a second operating state in which a load current for generating a DC voltage flows from the power grid to the power-supply unit, such that the control circuit turns on the switching element for a first time period during switching of the power-supply unit from the first to the second operating state, to turn the bistable relay on during the first time period, and to turn the switching element off at the end of the first time period.

Abstract: An isolated switched mode power supply (SMPS) is disclosed. The SMPS comprises a switching controller to generate start-up and operational switching control signals. The SMPS further includes a transformer, having a primary winding, and a full-bridge drive circuit to drive the primary winding. The full-bridge drive circuit comprises a first switching element, a boot-strap dnving circuit, and a second switching element. The switching controller is further used to start up isolated SMPS by determining a duty cycle for operational control signals and generating the start-up switching control signals.

Abstract: A method and a control device control a switching device for providing a resonant circuit with a switching voltage for generating a resonant current in order to provide a required output power at an output of a resonant power converter.

Abstract: A circuit module includes: control object circuits which start operations when a power supply voltage reaches a target value; a current sink circuit which consumes a current supplied thereto; and a power supply activation control unit which increases the current flowing into the current sink circuit at a predetermined rate before starting the operations of the control object circuits and which starts the operations of the control object circuits and simultaneously blocks the supply of the current to the current sink circuit in a case where an amount of the current flowing into the current sink circuit is equivalent to an amount of current to be increased by starting the operations of the control object circuits when the power supply voltage reaches the target value.

Abstract: The present invention discloses an integrated device with AC to DC conversion function, and an integrated circuit using the device. The integrated circuit comprises: a circuit operating under low DC voltage; and an integrated device with AC to DC conversion function, the device including first, second, third and fourth diodes, wherein the first diode has a cathode coupled to an anode of the second diode at a first node which receives an input of an AC voltage; the third diode has a cathode coupled to an anode of the fourth diode at a second node which receives another input of the AC voltage; the first diode has an anode coupled to an anode of the third diode at a third node which provides a low level of a DC voltage; and the second diode has a cathode coupled to a cathode of the fourth diode at a fourth node which provides a high level of the DC voltage.

Abstract: An in-rush or out-rush current limiting circuit employs a low number of components to effect in-rush current limiting and may be employed in dongles or on-chip (in the case of serving as an out-rush current limiting circuit). The in-rush current limiting circuit may be employed, for example, in USB dongles, Display Port (DP) dongles, or any other suitable connector as desired. Alternatively, the circuit may be integrated onto a circuit board or within an integrated circuit as desired. Among other advantages, a lower cost, low complexity solution may be provided. In addition, bulk capacitance can be increased such as by employing a trickle resistor or other suitable limiting structure.

Abstract: A power supply control device includes a boost type power supply controller boosting an input voltage, a step down power supply controller reducing an output of the boost type power supply controller to output an output voltage, a first control loop including the boost type power supply controller, and a second control loop including the step down power supply controller, wherein the output voltage is controlled by the second control loop during a predetermined period beginning after the power supply control device enters a power-on state, and wherein the output voltage is controlled by the first control loop after the predetermined period passes.

Abstract: A DC/DC converter comprising voltage conversion circuitry for generating a regulated output voltage responsive to an input current and at least one switching control signal. A current control loop generates the at least one switching control signal to limit an input current responsive to the input current, a reference voltage and a slope signal injected with the reference voltage.

Abstract: A constant-voltage circuit converts a voltage input to an input terminal and outputs a predetermined constant voltage from an output terminal. The constant-voltage circuit includes an output transistor to output an electrical current to the output terminal in response to a control signal, a reference voltage circuit to generate a predetermined reference voltage, a control circuit to adjust a voltage proportional to the output voltage output from the output terminal to the reference voltage output from the reference voltage circuit by controlling the output transistor and a soft start circuit including a capacitor for soft start that is charged at start-up and a current control unit to control an electrical current supplied to the reference voltage circuit. The current control unit adjusts the reference voltage to a voltage determined by the capacitor for soft start at the start-up until the reference voltage reaches a desired voltage.

Abstract: An inrush current suppressing circuit connected between a power supply and a working circuit of an electronic device includes a first power supply circuit and a second power supply circuit both connected between the power supply and the working circuit. The first power supply circuit suppresses inrush current and forwards power from the power supply to the working circuit when the electronic device is powered on. The second power supply circuit forwards power from the power supply to the working circuit when the power supply reaches a predetermined voltage.

Abstract: A system and method are provided for a PTAT cell with no resistors which can operate at low power, has less sensitivity to process variation, occupies less silicon area, and has low noise. Further, a system and method are provided to scale up the reference voltage and current through a cascade of unit cells. Still further, a system and method are provided for PTAT component to be fine-tuned, advantageously providing less process variability and less temperature sensitivity.

Abstract: An inrush current protection circuit for charging a load to a target voltage, in which the inrush current protection circuit includes a first charging circuit and a second charging circuit. The first charging circuit charges a load to a first stage voltage, and there is a voltage difference existing between the target voltage and the first stage voltage. The second charging circuit charges the load form the first stage voltage to the target voltage, in which the first charge circuit charges slower than the second charging circuit.

Abstract: A power supply circuit includes a direct current (DC) voltage source, a protecting circuit having a first switching element, a pulse width modulation (PWM) circuit having a first terminal, a switching circuit, and a transformer. The DC voltage source is configured to provide a first DC voltage. The first terminal is configured to receive the first DC voltage via the first switching element to enable the PWM circuit. The PWM circuit is configured to switch on or switch off the switching circuit. The transformer is configured to convert the first DC voltage to an alternating current (AC) voltage in cooperation with the switching circuit.

Abstract: A method and apparatus for a flyback converter estimate the next value of the current limit for the flyback converter according to a present current limit value to achieve the maximum output power control of the flyback converter. An arithmetic circuit is used to calculate the next current limit value according three parameters, the present current limit value, the value of the current sense signal taken after a first time period counting from the instant when the present duty is triggered, and the variation of the current sense signal during a second time period, thereby narrowing the tolerance of the output power from the flyback converter.

Abstract: An electronic device includes a circuit protection unit providing over-current protection to a main circuit and including a series connection of first and second current limiting circuits, and a normally-open branch circuit coupled in parallel to the first current limiting circuit and operable to conduct when a voltage across the first current limiting circuit reaches a first predetermined threshold voltage not greater than an endure voltage of the first current limiting circuit. Prior to conduction of the branch circuit, the first current limiting circuit maintains a current flowing therethrough at a first limit value when a current flowing through the main circuit reaches the first limit value. Upon conduction of the branch circuit, the second current limiting circuit maintains a current flowing therethrough at a second limit value greater than the first limit value when the current flowing through the main circuit reaches the second limit value.

Abstract: A power supply device has an error amplifier producing an error voltage by amplifying a difference between a feedback voltage according to an output voltage and a predetermined reference voltage, an output portion producing a desired output voltage from an input voltage in such a way that the error voltage is reduced, and a clamping portion setting, during a predetermined period after startup of the power supply device, an upper limit of the error voltage to a value that is lower than a value obtained at normal times, such that the lower the input voltage the higher the upper limit, the higher the input voltage the lower the upper limit.

Abstract: A PSE configured to determine the end of the start up phase at the PD responsive to a condition of the voltage at the PSE output. In one particular embodiment, the startup phase end is determined responsive to a PSE output voltage within a predetermined range of the PSE input voltage. In another particular embodiment, the startup phase end is determined responsive to the voltage drop associated with the PSE current limiter being lower than a predetermined maximum. In yet another particular embodiment, the startup phase end is determined responsive to the absolute value of the rate of change of the PSE output voltage being lower than a predetermined value. In yet another particular embodiment, the startup phase end is determined responsive to the absolute value of the rate of change of the voltage drop associated with the PSE current limiter being lower than a predetermined value.

Abstract: A device for precharging a voltage converter is provided with a precharging unit, capable of assuming a closed state, as well as with a control unit for the precharging unit, the precharging unit being capable of operating according to a precharging state limiting the value of the precharging current passing through it, the control unit being capable of commanding the operation of the precharging unit according to the precharging state and, once the precharging has been completed, of commanding the precharging unit to change over from the precharging state to the closed state. The assembly has a chopping voltage converter and such a device disposed at the input of the converter. The aircraft is equipped with such a device or with such an assembly.

Abstract: A control system of a laptop computer storage system comprises a plurality of receptacles for charging one or more laptop computer batteries. A first switch may be provided for coupling the receptacles to a power source via a current limiter having an impedance that initially limits a current inrush and then decreases with temperature. A second switch may be provided for coupling the receptacles to the power source via a low impedance path. A controller may be provided and configured to activate the first switch to limit an initial current inrush while charging energy storing components associated with the laptop computer's power supply and then activate the second switch to allow each laptop coupled to the receptacles to at least partially charge its battery.

Abstract: Provided are a method and apparatus for improving the power factor of an input power. The apparatus includes an input unit receiving the input power, a power factor correction unit correcting the power factor of the input power applied to the input unit, and a saturation prevention unit controlling the power factor correction unit such that the corrected power does not exceed a set power limit.

Abstract: A circuit is provided including an output stage with a pair of transistors. Further provided is a control circuit in communication with the output stage. The control circuit is capable of controlling a duration in which at least one of the transistors is actuated for reducing an in-rush current.

Abstract: A circuit for minimizing voltage inrush upon startup in a switching power converter having a switching stage including high and low switches connected at a common node, a feedback loop for maintaining a target output voltage, an output capacitor connected between an output node and the ground, an inductor connected between the common node and the output node, and a control circuit having a first error amplifier for providing a first signal based on a comparison of a reference voltage and voltage provided by the feedback loop, the control circuit including a level switch connected between the ground and the common node, the level switch being controlled in accordance with the first signal, wherein a large inrush current flowing into the output capacitor when the circuit is starting up is minimized.

Abstract: A synchronous-rectification-type switching regulator is disclosed that includes a first switching element; an inductor charged with a voltage input to an input terminal of the switching regulator by the switching of the first switching element; a second switching element for synchronous rectification performing switching so as to discharge the inductor; a control circuit part controlling the switching of the first switching element so that an output voltage from an output terminal of the switching regulator is a predetermined constant voltage, and to cause the second switching element to perform the switching inversely to the first switching element; and a reverse current prevention circuit part interrupting a current that flows into the second switching element by cutting off the connection of the second switching element so as to prevent generation of a reverse current that flows in the direction of the second switching element from the output terminal.

Abstract: An inrush voltage clamping circuit for an electronic device for clamping an inrush voltage induced by hot plugging is disclosed. The clamp circuit includes a buffer unit and a clamp unit. The buffer unit is coupled to an input power end for receiving an inrush current of the inrush voltage. The clamp unit is coupled to the input power end and the buffer unit for controlling the buffer unit to receive the inrush current according to an input voltage of the input power end.

Abstract: A switching regulator includes a first switch, an inductor, a second switch, a controller to control a switching operation by switching the first switch and switching the second switch complementally to the first switch, and a reverse current detector to detect a reverse current that flows from an output terminal toward the second switch. The reverse current detector generates a proportional voltage that is proportional to a voltage at a junction node between the second switch and the inductor, and detects a generation or an indication of the reverse current based on the proportional voltage. The controller turns the second switch off to create a shutdown state when the reverse current detector detects the generation or the indication of the reverse current.

Abstract: A high voltage start-up circuit with constant current control applied to a switching mode power converter is provided. The high voltage start-up circuit includes a high voltage junction transistor, a control transistor, a current detecting resistor and a bias resistor. The drain of the junction transistor is connected to a high power supply, the gate of the junction transistor is connected to the drain of the control transistor, and the source of the junction transistor is connected to the current detecting resistor. The voltage drop crossing the current detecting resistor is kept constant to have the junction transistor output a constant current. The bias resistor which is connected between the gate of the junction transistor and the output end of the high voltage start-up circuit has the gate to source bias voltage of the junction transistor kept constant to output constant current.

Abstract: One embodiment of the present invention includes a power supply system. The power supply system comprises a variable voltage source configured to provide and incrementally increase a control voltage associated with a pass-transistor. The power supply system also comprises an inrush current monitor configured to monitor a current-flow through the pass-transistor. The power supply system further comprises a voltage control circuit configured to halt the incremental increase of the control voltage in response to the current-flow exceeding a predetermined current limit.

Abstract: A power supply apparatus with an inrush current prevention circuit is applied to a parallel power bus. The power supply apparatus includes a filter capacitor and a current control unit. The current control unit is electrically connected to the filter capacitor. The current control unit controls a charged current flowing through the filter capacitor to prevent an inrush current generated in the parallel power bus.

Abstract: Aspects of a method and system for a power switch with a slow in-rush current are presented. Aspects of the system may include at least one resistive component, which is coupled between an input control signal and an output stage circuit of a power switch circuit, so as to limit a peak transient current level, which may result from in-rush current delivered by the power switch circuit to a load impedance circuit during a transient time interval during which a voltage level across the load impedance circuit may rise or fall from an initial voltage level to a quiescent voltage level.

Abstract: Various systems and methods for providing a pulse width modulation soft start feature in a redundant power supply are disclosed. One method involves comparing an input voltage, which is received from a load unit, to a threshold voltage. If the input voltage is less than the threshold voltage, a PWM signal is used to control a switch, which is configured to electrically couple a redundant power supply to the load unit when closed. The duty cycle of the PWM signal is then modified according to a predetermined sequence.

Abstract: Provided is a voltage regulator for limiting a rush current from an output stage transistor. The voltage regulator includes an output current limiting circuit having a low detection current value and an output current limiting circuit having a high detection current value, and is structured so as to enable operation of the output current limiting circuit having a low detection current value during a time period from a state in which an overheat protection circuit detects overheat and an output current is stopped to a state in which an overheat protection is canceled and a predetermined time passes. Accordingly, after the overheat protection is cancelled, an excessive rush current can be limited.

Abstract: To suppress the magnetizing inrush current occurring when supplying power of three phases of the transformer are performed simultaneously using three single-phase circuit breakers or a non-phase segregated operation-type circuit breaker, without providing a circuit breaker with a resistor or other equipment. A magnetizing inrush current suppression method for transformer suppresses a magnetizing inrush current occurring at the start of energizing of a three-phase transformer 300, when a three-phase power supply 100 is input to a terminal of each phase by means of a three-phase circuit breaker 200.

Abstract: A switching power converter with a controlled startup mechanism includes a switching stage which provides a voltage Vout at an output node in response to a switching control signal, with the output node adapted for connection to a non-linear load. A feedback network compares a signal which varies with the current conducted by the load (Iload) with a reference signal, and provides the switching control signal so as to maintain Iload at a desired value. A capacitor connected to the output node provides a current Ic to the feedback network which varies with dVout/dt. The feedback network is arranged to limit dVout/dt in response to current Ic when Iload is substantially zero. In this way, large inrush currents or damage that might otherwise occur during startup are avoided.

Abstract: An active start judgment circuit is electrically connected to an AC/DC transforming power supply which has at least one standby power unit to transform AC to DC in regular conditions and a main power unit to transform the AC to the DC in an ON condition for operation of an electronic equipment. The start judgment circuit bridges the standby power unit and the main power unit, and generates a reference potential based on a voltage output from the standby power unit, and gets a power signal from the standby power unit to be compared with the reference potential to output a start signal to the main power unit to transform the AC to the DC. Thus the standby power unit can actively drive the main power unit to supply DC power to activate the electronic equipment.

Abstract: Provided is a switching regulator for preventing generation of an inrush current flowing through a switching element of an output stage, which is provided in the switching regulator. A soft start control circuit (116) detects a current flowing through a PMOS transistor (104) serving as a switching element of an output stage. When the detected current is equal to or larger than a current limiting value for limiting the current flowing through the PMOS transistor (104), the soft start control circuit (116) controls the PMOS transistor (104) to be turned off. Accordingly, it is possible to prevent generation of the inrush current flowing through the PMOS transistor (104).

Abstract: A method for operating a current limit power switch for supplying power to a load include activating the power switch to start supplying power to the load; limiting the current drawn by the power switch to a first current limit for a first, fixed duration; after the first, fixed duration, limiting the current drawn by the power switch to a second current limit for a second duration where the second current limit is less than the first current limit; and after the second duration, limiting the current drawn by the power switch to a third current limit where the third current limit is less than the second current limit.

Abstract: A method for operating a device in which typically a very high current is generated when the device is turned on compared to the rated current, e.g. an analogue operated PTC heating device for a mobile device, such as a vehicle, is disclosed. In this method, the power on the device is increased in a defined limited manner or in a ramp-like manner in the connection phase to avoid a high current when the device is switched on.

Abstract: A boost converter in which the conventional boost diode is replaced by a bidirectional normally conducting semiconductor switch. The circuit may be implemented so the bidirectional switch is self-driven by connecting a low voltage Schottky diode between a first gate-source terminal pair. An inrush current protection function may be provided by utilizing a second gate-source terminal pair to turn the switch on and off independent of the self-driven operation in response to predetermined excessive load current conditions. The inrush current protection function is implemented by use of a second Schottky diode connected between the second gate and source terminals, and an RC circuit connecting the second gate terminal to the return rail for the converter power output transistor with an externally controlled switch connected to the RC circuit to control the bias according to the load current.