Abstract: System and method for regulating a power converter. The system includes a comparator configured to receive a first signal and a second signal and generate a comparison signal based on at least information associated with the first signal and the second signal. The first signal is associated with at least an output current of a power converter. Additionally, the system includes a pulse-width-modulation generator configured to receive at least the comparison signal and generate a modulation signal based on at least information associated with the comparison signal, and a driver component configured to receive the modulation signal and output a drive signal to a switch to adjust a primary current flowing through a primary winding of the power converter. The modulation signal is associated with a modulation frequency corresponding to a modulation period.

Abstract: A driver circuit is provided for lighting means, in particular for one or more LEDs, having an LLC circuit with an inverter which is clocked by means of at least two switches and is designed to supply a resonant circuit, wherein the resonant circuit is coupled to a primary winding of a transformer for transforming electrical energy from the primary winding to a secondary winding, and the lighting means can be supplied with current starting from the secondary winding, having a control unit which is designed to control the switch of the inverter after an activation of the driver circuit during a start phase, in such a way that after a single or after multiple alternating cycles of the switch, the cycling of the switch is suspended for the duration of at least one alternating cycling of the switch until a criterion for ending the start phase is satisfied.

Abstract: A semiconductor device for power supply control includes an on/off control signal generation circuit which generates a control signal for turning on or off a switching element; a current detection terminal to which voltage in proportion to a current flowing in a primary-side winding wire of a transformer is input; a pull-up unit with high impedance provided between the current detection terminal and a terminal to which an internal power supply voltage is applied; and a terminal monitoring circuit which determines that the current detection terminal is abnormal when comparing the voltage of the current detection terminal with a predetermined voltage and detecting that the voltage of the current detection terminal is higher than the predetermined voltage. When the terminal monitoring circuit detects abnormality of the current detection terminal, a signal generation of the on/off control signal generation circuit is stopped by a signal output from the terminal monitoring circuit.

Abstract: Embodiments of a saturation controller for a flyback switched-mode power supply (SMPS) and a method for saturation control for a flyback SMPS involve measuring a length related to a primary stroke in the flyback SMPS, comparing the length related to the primary stroke to a length related to a previous primary stroke in the flyback SMPS to generate a comparison result and adjusting a switching period time of the flyback SMPS based on the comparison result such that saturation of the flyback SMPS is reduced.

Abstract: A composite electronic component includes a composite body in which a common mode filter and a multilayer ceramic capacitor array are coupled to each other, the common mode filter including a first body having a common mode choke coil, and the multilayer ceramic capacitor array including a second body in which a plurality of dielectric layers are stacked.

Abstract: A machine learning apparatus includes a state observation unit which observes a state variable including at least one of data associated with the value of a DC voltage in a DC link, data associated with the amount of power supply regeneration representing the amount of power returned from the DC link to an AC power supply by a power supply regeneration operation by a converter, and data associated with the occurrence or nonoccurrence of an overvoltage alarm indicating that the DC voltage of the DC link has exceeded a preset overvoltage alarm level, and a learning unit learns conditions associated with the power supply regeneration operation by the converter, in accordance with a training data set defined by the state variable.

Abstract: A composite electronic component includes a composite body in which a common mode filter and a multilayer ceramic capacitor array are coupled to each other, the common mode filter including a first body in which a common mode choke coil is disposed, and the multilayer ceramic capacitor array including a second body in which a plurality of dielectric layers are stacked.

Abstract: A method for the start-up and/or the maintenance of a supply voltage for a driver circuit for a solid state light source is described. The driver circuit comprises a switched-mode power converter with a switch and a transformer. The switched-mode power converter converts an input voltage into an output voltage. The driver circuit has a controller which generates a gate control signal for putting the power converter switch into an on-state or an off-state. The driver circuit comprises a supply voltage capacitor to provide a voltage to the controller. A primary coil of the transformer is arranged in series with the power converter switch. A secondary coil arrangement of the transformer provides the output voltage. and is coupled to the supply voltage capacitor via a supply voltage transistor which is controlled such that the supply voltage provided by the supply voltage capacitor lies within a pre-determined voltage interval.

Abstract: A flyback power converter circuit includes: a transformer, including a primary winding coupled to an input power and a secondary winding coupled to an output node; a primary side switch coupled to the primary winding for switching the input power to generate an output power on the output node through the secondary winding; a clamping circuit including an auxiliary switch and an auxiliary capacitor which are connected in series to form an auxiliary branch which is connected with the primary winding in parallel; and a conversion control circuit adjusting an auxiliary dead time according to a primary side switch related signal and a switching voltage related signal such that the primary side switch is zero voltage switching at a time point when the primary side switch is turned ON.

Abstract: In a driving device, a resistor is provided on a current path connected to an on-off control terminal of a switching element. The current path permits a drive current to flow therethrough to or from the on-off control terminal of the switching element. A switching rate setter sets a switching rate of switching the switching element from one of an on state and an off state to the other thereof. A current adjusting unit includes an open-close control element provided on the current path for electrically opening or closing the current path. The current adjusting unit is configured to adjust, according to the switching rate set by the switching rate setter, the drive current flowing through the current path and the resistor while closing the open-close control element.

Abstract: A magnetic stripe transmission (MST) apparatus that improves a recognition rate and operates at a low current is provided. The apparatus includes a first coil disposed between a first power supply source and a second power supply source, and wound in a first direction, a second coil connected in parallel to the first coil, disposed between the first power supply source and the second power supply source, and wound in a second direction, a first driver disposed between the first coil and the second power supply source, and configured to control a first current of the first coil according to a first voltage pulse supplied by a first pulse supply source, and a second driver disposed between the second coil and the second power supply source, and configured to control a second current of the second coil according to a second voltage pulse supplied by a second pulse supply source.

Abstract: A switching power supply apparatus includes a switching circuit, a resonance circuit, a rectifying circuit, and a control circuit. The switching circuit includes switching elements connected in series between input terminals of a source. The resonance circuit includes an excitation inductor of a primary winding of a transformer, a resonance inductor connected in series with the excitation inductor, and a variable resonance capacitor which is connected in series with the excitation inductor and whose electrostatic capacity changes according to a control voltage. The control circuit generates, on the basis of a feedback voltage, switching signals in which frequency diffusion is given to a switching frequency and the control voltage and outputs the switching signals and the control voltage to simultaneously change the switching frequency and the electrostatic capacity of the variable resonance capacitor.

Abstract: System and method for regulating a power conversion system. A system controller for regulating a power conversion system includes a first controller terminal and a second controller terminal. The system controller is configured to receive at least an input signal at the first controller terminal, and generate a gate drive signal at the second controller terminal based on at least information associated with the input signal to turn on or off a transistor in order to affect a current associated with a secondary winding of the power conversion system. The system controller is further configured to, if the input signal is larger than a first threshold, generate the gate drive signal at a first logic level to turn off the transistor.

Abstract: A method of controlling a power supply includes detecting a transition of the power supply to discontinuous conduction mode (DCM), and locking an operating point of the power supply after detecting the transition. The operating point can be unlocked when a timer expires or when a feedback voltage slope exceeds a threshold.

Abstract: Automatic transfer switching apparatus and systems include a switching device including an input line, a sensor, and a parallel assembly of a solid-state relay and latching relay electrically connected with the input line. The solid-state relay is used to short the latching relay such that the latching relay can be opened and/or closed in an unloaded state while the input line is energized.

Abstract: A power converter has a power transistor and inductor coupled in a conduction path with the power transistor. A switching frequency of the power transistor is reduced during a light load condition. A pulse width of a drive signal to the power transistor is controlled to select a current through the inductor and power transistor corresponding to the switching frequency to maintain a fixed output power of the power converter, and further to vary the current through the inductor and power transistor to maintain the fixed output power of the power converter over a range of switching frequencies. A first number of pulses of the drive signal to the power transistor during a first time period sets the fixed output power of the power converter. No pulses of the drive signal are provided during a second time period after the first time period.

Abstract: A first capacitor and an auxiliary power supply are provided to a secondary side of an insulated synchronous rectification DC/DC converter, in addition to a synchronous rectification transistor and a secondary-side controller. One end of the first capacitor is connected to a first node that connects the synchronous rectification transistor and a secondary winding. The auxiliary power supply charges the first capacitor using the voltage VOUT supplied via the output line, so as to stabilize the voltage across the first capacitor. The ground voltage is supplied to the secondary-side controller via the first node. Furthermore, the power supply voltage is supplied to the secondary-side controller via the other end of the first capacitor.

Abstract: This invention, is concerning a signal voltage device, in which transformers 22a, 22b and a reception circuit 24 are formed on the same chip, and accordingly, no ESD protective element connected to a transformer connection terminal of the reception circuit 24 is required, and negative pulses generated in reception-side inductors 11 can be used in signal transmission. Signal transmission using both positive pulses and negative pulses is made possible as a result, and a stable signal transmission operation can be carried out even in a case where delay time varies in a signal detection circuit. Further, a reception circuit of low power consumption can be configured by using a single-ended Schmitt trigger circuit 14 in the signal detection circuit.

Abstract: A power control method for an electronic device including a built-in battery and detachably connected to an external adaptor, including: detecting whether the external adaptor is connected to the electronic device; obtaining information regarding the external adaptor when the external adaptor is connected to the electronic device; estimating a current value according to the information regarding the external adaptor and an amount of power consumption of the electronic device; and controlling the battery to output a fixed current according to the current value to supply power to the electronic device, wherein at this time the electronic device is powered by both the external adaptor and the battery.

Abstract: A method for estimating an output voltage of a power converter comprises sensing a voltage waveform representative of the output voltage; and detecting a first gap and a second gap. The first gap is between a time when the sensed voltage waveform crosses a first voltage reference and a time when the sensed voltage waveform crosses a second voltage reference at a voltage offset below the first voltage reference. The second gap is between a time when the sensed voltage waveform crosses a third voltage reference and a time when the sensed voltage waveform crosses the second voltage reference, the third voltage referenced at a predetermined voltage above the second voltage reference. Responsive to the first gap exceeding a threshold, a tracking error is computed based on the first gap; and responsive to the first gap not exceeding the threshold, the tracking error is computed based on the second gap.

Abstract: Systems and methods for supplying power at a medium voltage from an uninterruptible power supply (UPS) to a load without using a transformer are disclosed. The UPS includes an energy storage device, a single stage DC-DC converter or a two-stage DC-DC converter, and a multi-level inverter, each of which are electrically coupled to a common negative bus. The DC-DC converter may include two stages in a unidirectional or bidirectional configuration. One stage of the DC-DC converter uses a flying capacitor topology. The voltages across the capacitors of the flying capacitor topology are balanced and switching losses are minimized by fixed duty cycle operation. The DC-DC converter generates a high DC voltage from a low or high voltage energy storage device such as batteries and/or ultra-capacitors. The multi-level, neutral point, diode-clamped inverter converts the high DC voltage into a medium AC voltage using a space vector pulse width modulation (SVPWM) technique.

Abstract: A semiconductor device, for controlling a power supply which generates and outputs a driving pulse, includes: a clock generating circuit with an oscillating circuit in which a frequency can be changed and which generates a clock signal; a voltage/electric current control circuit which provides timing to turn off a switching element; a setting terminal to provide setting information from outside; a switch between a first power supply terminal and a second power supply terminal; and an internal power supply voltage control circuit which controls the switch. When voltage of the setting terminal is lower than a first voltage value, the device advances to a first stop mode in which output of a driving pulse is stopped. When voltage of the setting terminal is higher than the first voltage value, the device advances to a second stop mode in which the output of the driving pulse is stopped.

Abstract: A power system includes power conversion circuitry that has a first switch and a second switch on either side of a transformer. The system also includes gate driver circuitry that operates the first switch and the second switch. Power transfer in a normal operating mode from a primary side to secondary side of the DC-DC power conversion circuitry is controlled by operating the first switch. The system can recover voltage from the secondary side to the primary side by reversing a direction of power transfer when a voltage on the primary side of the DC-DC power conversion circuitry is less than an operating voltage of the gate driver circuitry. The system can resume the normal operating mode when the voltage on the primary is greater than the operating voltage of the gate driver circuitry.

Abstract: A circuit for detecting a knee of waveform is disclosed in the present invention. The circuit detects the knee and a total oscillation time of a voltage waveform as a load switch of load circuit is turned off. In the circuit, a filter filters the voltage waveform to transmit a reference voltage to a first and a second comparator. When the first and the second comparator determine that the voltage waveform achieves a sum of the reference voltage and a set voltage, the first and the second comparator transmit a first and a second signal to a knee detection module. When the knee detection module receives the first signal rather than the second signal in an oscillation time, or receives the second signal rather than the first signal in the oscillation time, the knee detection module records the knee and trigger a time recorder computes the total oscillation time.

Abstract: A converter includes a first bridge arm, a second bridge arm, two switch units and a voltage clamp circuit. The first bridge arm includes a first switch unit and a second switch unit that are electrically coupled in series at an output terminal. The second bridge arm includes two voltage sources that are electrically coupled in series at a neutral point terminal. The two switch units are electrically coupled in series at a common connection terminal, and are arranged between the neutral point terminal and the output terminal. The voltage clamp circuit is electrically coupled to the output terminal, the common connection terminal, the neutral point terminal, and one of a positive input terminal or a negative input terminal, and the circuit is shared by the two switch units to clamp voltages across the two switch units.

Abstract: A multi-output power supply includes: a switching element that turns ON and OFF currents flowing through all primary coils of a plurality of transformers connected in parallel at a same time; a plurality of output circuits that rectify and smooth voltages induced in secondary coils of the plurality of transformers to produce a plurality of output voltages; a plurality of feedback voltage detection circuits that detect feedback voltages corresponding to the output voltages of the plurality of the output circuits; an averaging circuit that calculates an average feedback voltage from the feedback voltages detected by the feedback voltage detection circuits; and a control circuit that uses feedback control to turn the switching element ON and OFF according to the average feedback voltage calculated by the averaging circuit.

Abstract: A power factor correction circuit includes an overcurrent protection circuit, and the overcurrent protection circuit detects at least one of a line input voltage, a switch current of a power factor correction circuit, and a line period peak and performs overcurrent protection operations using a detection result.

Abstract: A flyback converter can include: a power switch controlled to be turned on/off to control a current through a primary side; a first primary winding coupled between an input terminal and a first terminal of the power switch, where a dotted terminal of the first primary winding is coupled to a first terminal of the power switch; a second primary winding coupled between a second terminal of the power switch and a primary grounding terminal, where a dotted terminal of the second primary winding is coupled to the primary grounding terminal; a secondary winding configured between the first and second primary windings in a radial direction of a magnetic core, where the first primary winding, the second primary winding, and the secondary winding are wound around the magnetic core; and a secondary rectifier and filter circuit coupled with the secondary winding, and configured to generate a stable current/voltage.

Abstract: A power conversion device that distributes input power to multiple outputs in accordance with power requirement of a load, using a plurality of magnetically coupled windings. In the case of supplying power from an AC power supply, at least one of an AC/DC converter and first to fourth switching circuits controls voltage on an output side of the AC/DC converter, based on a deviation between a detected value and a target value of the voltage. In the case of supplying power from a first DC voltage source or a second DC voltage source, the second switching circuit or the fourth switching circuit provided between the first DC voltage source or the second DC voltage source and the transformer supplies power based on an arbitrary time ratio.

Abstract: A power-supply circuit includes a transformer with primary and secondary windings, and an energy accumulator on the secondary winding. A circuit monitors the secondary winding and generates a feedback signal that is transferred by a transmission circuit through the secondary winding by selectively transferring energy from the energy accumulator. The transmission circuit includes: a) an electronic switch having a control terminal; and b) a driver circuit for driving the electronic switch. The driver circuit includes a charge-accumulation capacitor connected to the control terminal, and a charge circuit configured to draw energy from the secondary winding and charge the charge-accumulation capacitor.

Abstract: An energy recovery snubber circuit for a power converter which includes a flyback transformer driven by a converter switch is disclosed. The snubber circuit includes two capacitors which are connected such that, when the snubber circuit is connected to a primary winding of the flyback transformer, the capacitors are charged in series by current flowing in a first direction in the primary winding when the converted switch is turned OFF, to recover energy stored in the leakage inductance of the transformer, and discharged in parallel to cause current flow in a second direction in the primary winding of the transformer, to thereby transfer the recovered energy to the transformer.

Abstract: Switched-mode power supply (SMPS) circuits and a method implemented within an SMPS are provided. The circuits and method use resonant energy capturing and filtering circuitry to provide an auxiliary power supply that may be used to power a controller of an SMPS. This circuitry includes a resonant circuit that recirculates and extracts energy at switch transitions of the SMPS. The circuitry required to implement the circuits and method is minimal, and provides advantages over techniques that require an additional power supply or that require an auxiliary winding in a transformer.

Abstract: A power system for a marine ship includes a plurality of protection zones, wherein at least two protection zones are coupled to each other via at least one bus-tie converter. Each of the protection zones includes a plurality of direct current (DC) buses and a plurality of power converters. The bus-tie converter includes at least two converter legs coupled by at least one inductor. Each converter leg includes a first branch connected with a snubber circuit by an intermediate switching device. The first branch includes two outer switching devices and at least one inner switching device connected between the two outer switching devices. The snubber circuit includes a combination of a diode, a resistor and a capacitor. A controller controls the operation of the plurality of power converters and the at least one bus-tie converter.

Abstract: Power switch devices having an overload limit are provided. The overload limit may be adjusted based on an inductance coupled with the power switch device.

Abstract: A control circuit applied to a power converter includes a multi-functional pin, a zero-crossing signal generator, and an over-voltage detector. The multi-functional pin is used for receiving an auxiliary current generated by an auxiliary winding of the power converter, and an input current. The zero-crossing signal generator is used for generating a zero-crossing signal according to the auxiliary current. The over-voltage detector is used for generating an over-voltage signal according to the auxiliary current. The control circuit generates a switch control signal to the power switch according to the zero-crossing signal, or generates an over-voltage protection signal to the power switch according to the over-voltage signal.

Abstract: A power system for a marine ship includes a plurality of protection zones, wherein at least two protection zones are coupled to each other via at least one bus-tie converter. Each of the protection zones includes a plurality of direct current (DC) buses and a plurality of power converters. The bus-tie converter includes at least two converter legs coupled by at least one inductor. Each converter leg includes a first branch connected with a snubber circuit. The first branch includes two outer switching devices and at least one inner switching device connected between the two outer switching devices. The first branch also includes a damping resistor coupled between the two outer switching devices to dissipate a fault current. The snubber circuit includes a combination of a diode, a resistor and a capacitor. A controller controls the operation of the plurality of power converters and the at least one bus-tie converter.

Abstract: A switch-mode DC converter configured to generate a converted voltage from an input voltage is provided. The switch-mode DC converter includes an inductor configured to store energy, and a switch coupled with the inductor at a switching node, wherein the switch is configurable to be turned on or off to control the discharging of the energy stored at the inductor to an output node of the converter, wherein the output node is configured to provide the converted voltage. The switch-mode DC converter also includes a circuit configured to control a timing of turning-off of the switch based on a voltage difference between the switch, wherein a measurement of the voltage difference is adjusted based on a voltage at the switching node.

Abstract: Lighting apparatus includes: AC/DC converter which converts AC voltage Vac to DC voltage Vdc; DC/DC converter which converts DC voltage Vdc to a DC voltage to be applied to LED; and detection circuit which detects AC voltage Vac. DC/DC converter includes switching element, and control circuit that performs a control of repeatedly turning on and off switching element in a boundary conduction mode. Control circuit performs the control under which ON time Ton is kept from exceeding an upper limit that is previously determined, and raises the upper limit when AC voltage Vac detected by detection circuit falls below a predetermined value. ON time Ton is a period of time during which switching element is kept ON.

Abstract: A power supply apparatus includes a power supply circuit and an active clamping circuit. The power supply circuit includes a secondary side rectifying unit and a voltage output side. The active clamping circuit includes a clamping energy-storing unit, a feedback control unit and a synchronous buck converter. The clamping energy-storing unit clamps and stores a voltage spike to obtain an energy-storing voltage. The feedback control unit detects the energy-storing voltage and informs the synchronous buck converter of the energy-storing voltage. The synchronous buck converter receives the energy-storing voltage and adjusts the energy-storing voltage to obtain an adjusted voltage when the energy-storing voltage is greater than a predetermined voltage. The synchronous buck converter sends the adjusted voltage to the voltage output side.

Abstract: There can be provided a power delivery (PD) device capable of achieving protocols, e.g. Hard Reset, without using any alternative power source, and a control method of thereof. The PD device includes: a power source; a power line configured to deliver power supplied from the power source, to an outside; a switch connected between the power source and the power line; and a control circuit connected to the power line so that power is supplied from the power source to the control circuit, wherein at the time when a Hard Reset protocol is received from the outside through the power line, the control circuit turns from ON to OFF the switch to disconnect the power line from the power source.

Abstract: A circuit and a method for evaluating a load condition in a flyback converter are disclosed. A first current source is used for providing a preset current ISUM equal to a sum of the off current value IOFF and the blanking current value ILEB to charge a first capacitor, and a second current source is used for providing a reference current IREF to charge a second capacitor. A comparator receives a voltage applied on the first capacitor at its positive input end and a voltage applied on the second capacitor at its negative input end. The output current transmitted to the load by the flyback converter is varied to the change of the preset current ISUM, as such the load condition is detected by the comparison result generated by the comparator.

Abstract: An AC/DC power conversion apparatus comprises an AC/DC converter for converting AC power to DC power for a load and a controller that maintains a power factor of the load as the load varies. The AC/DC converter includes an inductor and a plurality of switches that alternately connects and disconnects the inductor to and from an AC power source, to generate the DC power for the load. The plurality of switches is controlled by a plurality of switch drive signals generated by the controller, based on comparisons of an AC voltage from the AC power source to a DC output voltage produced by the AC/DC converter. To maintain the power factor of the load, the controller is configured to adjust the frequency of the plurality of switch drive signals in response to variations in the load while holding the duty cycles of the switch drive signals constant.

Abstract: A primary control LED driver includes: a switching converter having a main switch and a first winding, and configured to provide an LED driving current; a second winding magnetically coupled to the first winding and configured to provide a power supply voltage at a first terminal; a first sensing resistor with a first terminal coupled to the main switch; a second sensing resistor with a first terminal coupled to the second terminals of the first sensing resistor and the second winding; an output current calculator calculating an equivalent value of the LED driving current based on the voltage at the first terminal of the first sensing resistor; an error amplifier configured to generate a compensation signal based on the equivalent value and a reference voltage; and a control circuit generating a control signal to control the main switch based on the compensation signal.

Abstract: A switched mode power supply, SMPS. The SMPS comprises a switch, one or more inductors, an output smoothing capacitor, and a controller. The controller is configured to determine a first energy difference that is an instantaneous energy in the inductor(s) minus an energy in the inductor(s) at a load current, and determine a second energy difference that is an energy in the output smoothing capacitor at a reference voltage minus an instantaneous energy in the output smoothing capacitor. The controller is further configured to turn the switch on and off with a clock rate and a variable duty cycle such that the switch is on from the start of each period of the clock until the first energy difference is substantially equal to the second energy difference, and such that the switch is otherwise off.

Abstract: In various embodiments a method is provided for determining a demagnetization zero current time for a switched mode power supply having a transformer, a first side and a second side being galvanically separated from each other and a switched mode power supply controller, the method including: determining a first voltage being applied to one side of the transformer; determining a second voltage provided at the other side of the transformer; determining a time the first voltage is provided to a winding of the transformer; and determining, by a circuit located on the same side of the transformer as the switched mode power supply controller, the demagnetization zero current time using the determined first voltage, the determined second voltage and the determined time.

Abstract: Embodiments described herein describe a power supply configured to provide power to an output load via a power supply transformer. The power supply includes a controller configured to operate in a configuration state and an operating state. During the configuration state, the controller receives a configuration signal from a sense circuit coupled to the controller and selects one of a plurality of operating modes from the configuration signal. During the operating state, the controller controls a switch coupled to the transformer based on the selected operating mode and a sense signal received from the sense circuit representative of the power provided to the output load by the power supply. When the switch is closed, current flows from a power source through the transformer, and when the switch is open, current is prevented from flowing from the power source through the transformer.

Abstract: A second control circuit is configured to switch a pulse signal to a level which turns off a second switching transistor when a coil current that flows through a primary winding reaches a predetermined threshold current. The second control circuit is configured to start a switching operation when a power supply for an electronic device is turned on, to set the threshold current to a first value when an intermediate voltage is higher than a predetermined level, and to set the threshold current to a second value that is lower than the first value when the intermediate voltage is lower than a predetermined level. A first control circuit is configured to start a switching operation upon receiving an instruction from a microcontroller to start operating.

Abstract: A power supply system includes: a switching power supply operated in an on mode and an off mode; a mode controller for generating a pulse signal for designating the mode; an auxiliary power supply for feeding power to the mode controller; a power supply controller configured to be activated as the power is fed and to control an oscillation operation in accordance with the pulse signal generated by the mode controller; and a supply detector for detecting starting of the power feeding. The power supply controller executes: oscillating the switching power supply when the pulse signal is input during the oscillation stop; stopping the oscillation of the switching power supply when the pulse signal is input during the oscillation; and invalidating an input of the pulse signal for predetermined time when the supply detector detects the starting of the power feeding.

Abstract: A method of filtering a ripple can include: (i) generating, by a sampling circuit, a sense voltage signal that represents an output current flowing through a load; (ii) generating, by a filter circuit, a filter voltage signal by filtering the sense voltage signal, where the filter circuit includes a switch capacitor circuit and a filter capacitor; and (iii) generating, by an error amplifying circuit, an error compensation signal by amplifying a difference between the sense voltage signal and the filter voltage signal, where the error compensation signal is configured to compensate and regulate the output current flowing through the load by controlling a power switch that is coupled to the load and the sampling circuit.

Abstract: In one embodiment, the operating range of an over-current detection circuit is extended to higher input voltage levels by providing a reference-voltage generation circuit for the detection circuit with voltage protection circuitry that applies an additional voltage drop to shield other vulnerable transistor devices from the higher input voltages. In addition, bypass circuitry is provided that is inactive at the highest input voltage levels, but actively bypasses at least some of the voltage protection circuitry at relatively low input voltage levels to apply a voltage drop that is sufficient to ensure proper operation of the vulnerable transistor devices at the low voltage levels. In one implementation, the vulnerable transistor devices are NFET devices in a programmable current mirror of the reference-voltage generation circuit. In addition, a stiffened voltage divider helps to ensure sufficient voltage drop at the low voltage levels. The protection and bypass circuitry also enable hot-socketing operations.