Abstract: A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

Abstract: Various embodiments include a DC coupled electrical converter for converting an input voltage applied to first connections to an output voltage comprising: a boost converter connected on the input side to the first connections; an inverting buck-boost converter connected on the input side to the first connections; and a series circuit including two capacitors, the series circuit connected to an output-side positive pole of the boost converter and to an output-side negative pole of the inverting buck-boost converter. An output-side negative pole of the boost converter and an output-side positive pole of the inverting buck-boost converter are connected to a center connection between the capacitors.

Abstract: A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

Abstract: A voltage regulator for providing power to a system includes feedforward circuitry receiving a signal from the system indicating the current needed by the system, and the feedforward circuitry causes the voltage regulator to change the voltage regulator output current in response to the signal from the system.

Abstract: A power converter with a negative current detection mechanism is provided. A negative current detecting circuit includes a first operational amplifier, a first transistor and a second transistor. A non-inverting input terminal of the first operational amplifier is connected to a second terminal of a sense resistor. An inverting input terminal of the first operational amplifier is connected to a first terminal of a first capacitor. Control terminals of the first and second transistors are connected to an output terminal of the first operational amplifier. A first terminal of the first transistor is connected to the second terminal of the sense resistor. A second terminal of the first transistor is grounded. A first terminal of the second transistor is connected to the inverting input terminal of the first operational amplifier and the first terminal of the first transistor. A second terminal of the second transistor is grounded.

Abstract: In an embodiment, a current sensor unit includes: a rectification module, to convert an AC current to a pulsed DC current; a conversion module containing an energy storage element, to store energy based upon the pulsed DC current during a charging mode and to generate a power supply current based upon a voltage of the energy storage element; a mode switching module, bypassed by the conversion module during operation in the charging mode, and bypassing the conversion module during operation in an energy release mode; a current sensor module, to detect a pulsed DC current flowing back from the conversion module or mode switching module; a control module, to acquire electrical energy from the power supply current, determine that operation is in the charging mode or energy release mode based upon the voltage of the energy storage element, and acquire a detection value provided by the current sensor module.

Abstract: A switching regulator clamping the power or ground of the power switch driver is introduced. In a buck regulator, the power switch is coupled between the input terminal of the buck regulator and the first terminal of an inductor. The second terminal of the inductor is coupled to the output terminal of the buck regulator. There is a driver power clamp configured to clamp the ground terminal of the driver of the power switch. In a boost regulator, an inductor is provided which has a first terminal coupled to an input terminal of the boost regulator and has a second terminal coupled to the negative supply terminal of the power supply through a power switch. The boost regulator has a driver power clamp that is configured to clamp the power terminal of the driver of the power switch.

Abstract: A device includes a first FET coupled between first and drive terminals, and is configured to turn on/off responsive to a PWM signal having a first/second state, respectively. A second FET is coupled between the first and drive terminals and is configured to turn on responsive to the PWM signal having the first state, and turn off responsive to expiration of a particular delay after the second FET turns on. A third FET is coupled between drive and second terminals, and is configured to turn on/off responsive to the PWM signal having the second/first state, respectively. A fourth FET is coupled between the drive and second terminals, and is configured to turn on responsive to the PWM signal having the second state if a switching terminal has a first voltage, and turn off responsive to the PWM signal having the first state or the switching terminal having a second voltage.

Abstract: A light emitting load driving device includes a first constant current source structured to be serially connected to a first light emitting load group; a second constant current source structured to be serially connected to a second light emitting load group; a first load connection terminal structured to be connected to the first light emitting load group; a second load connection terminal structured to be connected to the second light emitting load group; and a control circuit structured to be supplied a first voltage applied to the first load connection terminal, a second voltage applied to the second load connection terminal, and a reference voltage applied to the control circuit, wherein the control circuit is structured to select a minimum voltage between the first voltage and the second voltage, and the control circuit is structured to equalize the minimum voltage and the reference voltage.

Abstract: A power conversion system is provided. The power conversion system includes N power conversion circuits. Each power conversion circuit includes an input, an output, two switching power conversion units and at least one resonant capacitor. The input and output are configured to receive an input voltage and output an output voltage respectively. Each switching power conversion unit includes a plurality of switches and a winding. The plurality of switches operates periodically according to a switching period. A dotted terminal of one winding is electrically coupled to an undotted terminal of the other winding. The two windings are magnetically coupled to each other to form a transformer. In one switching period, the resonant capacitor stores an energy or outputs the stored energy as the corresponding switch is turned on or off. A resonance is generated between the resonant capacitor and inductor with a resonant frequency and a resonant period.

Abstract: Exemplary embodiments may include a method of applying a charging pulse to an output capacitor, detecting satisfaction of a charging threshold, ending the charging pulse in response to the detecting the satisfaction of the charging threshold, and discharging the sampling capacitor in response to the detecting the satisfaction of the charging threshold. In some embodiments, once a sampling capacitor voltage drops below a discharging threshold, a charging pulse is applied. Exemplary embodiments may also include an apparatus with a controller coupled to an input node, a timer coupled to the controller, an inductive charger coupled to the controller, to an input node, and to an output node, and a sensor coupled to the controller and the output node. Exemplary embodiments may further include an apparatus where a sensor with a sampling capacitor has a first terminal coupled to the output node and a second terminal coupled to the controller and the inductive charger.

Abstract: An architecture for a multi-port AC/DC Switching Mode Power Supply (SMPS) with Power Factor Correction (PFC) comprises power management control (PMC) for PFC On/Off Control and Smart Power Distribution, and optionally, a boost follower circuit. For example, in a universal AC/DC multi-port USB-C Power Delivery (PD) adapter, PMC enables turn-on and turn-off of PFC dependent on output port operational status and a combined load of active output ports. A microprocessor control unit (MCU) receives operational status, a voltage sense input and a current sense input for each USB port, computes output power for each USB port, and executes a power distribution protocol to turn-on or turn-off PFC dependent on the combined load from each USB port. Available power may be distributed intelligently to one or more ports, dependent on load. In an example embodiment, turning-off PFC for low load and low AC line input increases efficiency by 3% to 5%.

Abstract: Disclosed are a household appliance, an apparatus and a method for detecting an arc fault in the household appliance. The apparatus includes: a grid current detecting unit, configured to detect a current from a power grid to the household appliance so as to generate a first current detecting signal; a filter protecting unit, configured to perform an attenuation processing on an arc signal in the power grid; a load current detecting unit, configured to detect an actual running current in a load of the household appliance so as to generate a second current detecting signal; and a control unit connected to the grid current detecting unit and the load current detecting unit respectively, and configured to identify and compare the first current detecting signal and second current detecting signal so as to determine a source of the arc fault.

Abstract: A voltage converter, which is configured as a step-down converter for reducing an input direct voltage to an output direct voltage lower than the input direct voltage, includes a first step-down converter circuit arrangement, having a first semiconductor switching element with a first control input, a first coupled choke having a first freewheeling diode, and a first input capacitor and a first output capacitor. A second step-down converter circuit arrangement, includes a second semiconductor switching element having a second control input, a second coupled choke having a second freewheeling diode, and a second input capacitor and a second output capacitor. An associated control device controls the voltage converter.

Abstract: A capacitor management circuit for a power management circuit, where the power management circuit includes a bidirectional converter having first and second ports, the capacitor management circuit includes a plurality of capacitor modules, and where each capacitor module includes: a switch and a capacitor coupled in series between two terminals of the second port; and a control circuit configured to detect state information of the corresponding capacitor, and to control operation state of the switch, in order to realize independent control of each capacitor.

Abstract: Resonant converters with wide voltage gain ranges are achieved by controlling at least one of the primary side resonant circuit and the secondary side rectifier circuit. A switch is included in at least one of the primary or secondary sides, and control of the switch according to a selected mode determines an output voltage of the resonant converter. Embodiments accommodate wide input and output voltage ranges, and are suitable for use in AC-DC power adapters for portable devices with different voltage requirements, such as cell phones, tablets, and notebook computers, as well as in DC-DC converter applications including electric vehicle power systems.

Abstract: An electric power apparatus for an electric arc furnace comprises at least one electrode and is connectable to a power network to supply to the electrode the electric energy to generate an electric arc to melt a metal mass. The apparatus comprises an electric regulation unit interposed and connected to the power network and to the electrode and configured to regulate at least one electric quantity for powering the electrode. The apparatus comprises at least one detection device to detect the electric quantity, interposed between the electrode and the electric regulation unit, a positioning device to move the at least one electrode nearer to/away from the metal mass to be melted and a control and command unit.

Abstract: A snubber circuit connected to a rectifying circuit including a reference potential node, an output potential node, and the snubber circuit comprises a snubber capacitor; a snubber diode; and a snubber resistor, wherein a negative electrode of the snubber capacitor is connected to the reference potential node, an anode of the snubber diode is connected to the switch node and a cathode of the snubber diode is connected to a positive electrode of the snubber capacitor, one end of the snubber resistor is connected to the positive electrode of the snubber capacitor, and another end of the snubber resistor is connected to the output potential node, and a reverse recovery time of the snubber diode is longer than a reverse recovery time of the rectifying element.

Abstract: An integrated circuit device includes a controller, an optional current source coupled to the controller, a voltage sampler coupled to the controller, a current detector coupled to the controller, and memory coupled to the controller, where memory includes code segments executable by the controller to: (a) apply a current pulse to a cell; (b) measure a voltage of the cell during the current pulse; (c) calculate an impedance of the cell from the measured voltage; and (d) determine an operational state of the cell from the impedance.

Abstract: The invention describes an apparatus (100) for transferring electrical power to an electrical load (110), comprising: a primary circuit (115), an electrical source (105) adapted for supplying said primary circuit with a direct input voltage, a secondary circuit (120) adapted for feeding the electrical load (110), and a coupling device (125) adapted for transferring electrical power from the primary circuit (115) to the secondary circuit (120), wherein the primary circuit (115) comprises: a converter (300) adapted for receiving the input voltage, for modifying said input voltage and for outputting said modified voltage, and a wave generator (190) comprising at least one switching circuit provided with at least one active switch (250), which is adapted for receiving in input the modified voltage in output from the converter (300), for converting said modified voltage into voltage waves and for applying said voltage waves to said coupling device (125), and wherein said converter comprises at least one active swi

Abstract: The Present invention is a measuring system including a measuring device 10 that is attached to a living body, the measuring device 10 being configured to store information about an amount of electric power generated using sugars in a body fluid or bodily secretion of a living body, and a container device 15 for storing the measuring device 10, the container device 15 receiving the information about the amount of electric power generated, which is stored in the measuring device 10, using a near-field wireless communication method when the measuring device 10 is stored in the container device 15.

Abstract: A power voltage generator includes a booster, a voltage sensor, a constant voltage controller and a constant current controller. The booster is configured to boost an input voltage to an output voltage based on an on-off operation of a switch. The voltage sensor is configured to generate a sensing voltage by sensing the output voltage. The constant voltage controller is configured to generate a first switching signal to control the switch by comparing the sensing voltage with a reference voltage. The constant current controller is configured to generate a gain based on a ratio of an electrode signal of the switch and a target signal by comparing the electrode signal of the switch with the target signal.

Abstract: Embodiments relate to a switching regulator having a dual mode control. The switching regulator includes an error amplifier configured to receive an output voltage of a power source, and to generate an error voltage based on a difference between the output voltage of the power source and a reference voltage. The switching regulator additionally includes a PFM controller configured to receive the error voltage from the error amplifier, and to generate a clock signal having a switching frequency based on a difference between the error voltage and a modulation voltage. Moreover, the switching regulator includes a PWM controller configured to receive the clock signal and an error signal determined based on a load current sensed at an output of the power source, and to generate a control signal to control the power source.

Abstract: A control unit for a switching converter has an inductor element coupled to an input and a switch element coupled to the inductor element and generates a command signal having a switching period to switch the switch element and determine a first time period in which an inductor current is flowing in the inductor element for storing energy and a second time period in which energy is transferred to a load. An input current is distorted relative to a sinusoid by a distortion factor caused by current ripple on the inductor current. The duration of the first time period is determined based on a comparison between a peak value of the inductor current and a current reference that is a function of an output voltage of said voltage converter. A reference modification stage modifies one of the current reference and sensed value of the inductor current to compensate for distortion introduced by the distortion factor on the input current.

Abstract: Various embodiments include a half-bridge comprising: a first power semiconductor; a second power semiconductor connected in series with the first power conductor; a controller for the power semiconductors; a line starting at connection node of the power semiconductors; and a meter for measuring the current in the line. The controller is configured to: compare the current with an upper threshold value and a lower threshold value; switch off the first power semiconductor if the upper threshold value is reached; switch on the second power semiconductor after a first dead time has elapsed; and switch off the second power semiconductor if the lower threshold value is reached; and switch on the first power semiconductor after a second dead time has elapsed.

Abstract: A concentration control circuit can include: a voltage feedback circuit configured to generate a current reference signal representing an error between a voltage reference signal and an output voltage feedback signal shared by each of a plurality of power stage circuits of a multi-phase power converter to adjust a respective phase current; and a clock signal generation circuit configured to generate a clock signal to adjust at least one of switching frequency and phase of each of the power stage circuits, where the clock signal is adjusted in accordance with a change of the current reference signal.

Abstract: An apparatus includes a plurality of parallel-connected semiconductor switches (e.g., silicon carbide (SiC) metal oxide semiconductor field effect transistors (MOSFETs) or other wide-bandgap semiconductor switches) and a plurality of driver circuits having outputs configured to be coupled to control terminals of respective ones of the plurality of semiconductor switches and configured to drive the parallel-connected semiconductor switches responsive to a common switch state control signal. The driver circuits may have respective different power supplies, which may be adjustable. Respective output resistors may couple respective ones of the driver circuits to respective ones of the semiconductor switches. The output resistors may be adjustable.

Abstract: According to one embodiment, a switching power circuit, includes: a switching transistor that is connected between an input terminal and a node; a driving circuit that supplies a PWM driving signal to the switching transistor; and a phase compensation circuit that supplies a feedback voltage to an error amplifier, in which the properties of the phase compensation circuit are switched in accordance with the voltage of the node immediately before the switching transistor is turned on.

Abstract: A control circuit is introduced for facilitating inrush current reduction for a voltage regulator providing an output voltage variable in response to an output voltage selection. The control circuit includes a soft-start circuit, a soft-start tracking circuit, and a controller. The soft-start circuit is utilized for providing a soft-start signal. The soft-start tracking circuit includes a first input terminal for receiving a feedback signal from the voltage regulator, a second input terminal coupled to the soft-start circuit, and an output terminal coupled to the soft-start circuit. The controller, coupled to the soft-start tracking circuit, is configured to output an enabling signal to the soft-start tracking circuit selectively in accordance with the output voltage selection. The soft-start tracking circuit is operable in response to the enabling signal so that the soft-start signal provided by the soft-start circuit substantially follows the feedback signal from the voltage regulator.

Abstract: A switched-mode power controller includes a primary side controller circuit configured in a startup mode of operation to generate a fixed switching frequency pulse width modulation (PWM) signal with incrementing duty-ratio value. The PWM signal drives a main-switch that charges an inductive device with stored energy and discharges the stored energy into a capacitor on a secondary side to generate a power controller output voltage. Based on a comparison of the power controller output voltage with a reference voltage, the primary side controller circuit is configured to stop the incrementing of the duty-ratio of the PWM signal and begin a quasi-resonant mode of operation during which the primary side controller circuit reduces a number of valleys detected in one or more off-times of the main-switch in one or more respective main-switch switching periods.

Abstract: An embodiment PFC control circuit includes a first terminal providing a drive signal to an electronic switch of a boost converter, a second terminal receiving a feedback signal indicative of an output voltage generated by the boost converter, and a third terminal connected to a compensation network. An error amplifier generates a current as a function of the voltage at the second terminal and a reference voltage, wherein an output of the error amplifier is coupled to the third terminal. A driver circuit generates the drive signal as a function of the voltage at the third terminal, and selectively activates or deactivates the generation of the drive signal as a function of a burst mode enable signal. A detection circuit generates the burst mode enable signal as a function of the voltage at the second terminal.

Abstract: A boost converter includes a voltage divider circuit, a first comparator, a tunable inductive element, a power switch element, a second comparator, an output stage circuit, and a controller. The voltage divider circuit receives an input voltage. The tunable inductive element is coupled to the voltage divider circuit. The total inductance of the tunable inductive element is controlled by the first comparator. The output stage circuit is coupled to the tunable inductive element and the power switch element. The output stage circuit includes a tunable resistive element. The total resistance of the tunable resistive element is controlled by the second comparator. When the boost converter operates in a first mode, an output voltage of the output stage circuit has a relatively high voltage level. When the boost converter operates in a second mode, the output voltage of the output stage circuit has a relatively low voltage level.

Abstract: An LED lighting driver has a switched mode power supply which generates an auxiliary power supply. The auxiliary power supply circuit has a first power supply inductor and a second power supply inductor in series with each other. The second power supply inductor is selectively switched into or out of the auxiliary power supply circuit, thereby varying a transformer ratio to the main energy storage inductor. The switching may be made based on a light output mode or a standby mode being in operation. The standby mode then enables more efficient generation of an auxiliary supply voltage.

Abstract: A timer includes a timing counter configured to generate a timing datum, a clock pulse signal generation circuit configured to generate a clock pulse signal used to operate the timing counter, and an interface circuit configured to receive an access signal, wherein the timing counter is an asynchronous counter, and the clock pulse signal generation circuit generates the clock pulse signal having a first pulse width when there is a possibility that the interface circuit receives the access signal, and generates the clock pulse signal having a second pulse width longer than the first pulse width when there is no possibility that the interface circuit receives the access signal.

Abstract: A power management integrated circuit (PMIC) can improve the ramp up speed of a boost converter with the inclusion of a controllable switch that may modify the connection of an output capacitor to reduce the ramp time as the output voltage is ramping to a desired boost setpoint. The switch may be controlled using jump start logic to switch a first plate or terminal of the output capacitor from a ground connection to a voltage supply connection. Once a threshold voltage is reached, the first plate of the capacitor may be switched from the supply voltage to ground. The PMIC may further include a quick start assembly that can drive the boost converter at a high duty-cycle.

Abstract: A power conversion system including a power conversion unit, a power circuit and a precharge circuit is provided. The power conversion circuit includes an input port, an output port, switching power conversion units and at least one storage device. The storage device is connected between the input and output ports in series. The power circuit is electrically connected to the power conversion circuit for receiving the input voltage and outputting a supply voltage to the power conversion circuit, and the power circuit includes a magnetic element. The precharge circuit precharges the storage device. The precharge circuit includes a winding and a rectifier filter circuit connected to each other. The winding is coupled to the magnetic element for receiving a conversion voltage. The rectifier filter circuit is electrically connected to the storage device so as to receive the conversion voltage and output a charge voltage to the corresponding storage device.

Abstract: A power conversion system is provided. The power conversion system includes a power conversion circuit, a bootstrap circuit and at least N driving circuits, where N is an integer larger than 1. The power conversion circuit includes an input port, an output port, N switching power conversion units and N nodes. The switching power conversion unit includes a first switch and a second switch. The bootstrap circuit includes N bootstrap capacitors and N bootstrap switches. The N bootstrap switches are serially connected in sequence. Two ends of the bootstrap capacitor are connected to the corresponding node and the second terminal of the corresponding bootstrap switch respectively. The first terminal of the (N)th bootstrap switch receives a supply voltage. The driving circuit is connected to the corresponding bootstrap capacitor and outputs driving signals for controlling the switches according to the positive electrode voltage of the bootstrap capacitor.

Abstract: An inverter device includes a converter circuit and an output circuit. The converter circuit generates a DC intermediate voltage based on a DC input voltage from a power source. The converter circuit includes: a first inductor and a first switch that are coupled in series across the power source; a second switch and a second inductor that are coupled in series across the power source; and a diode and a capacitor that are coupled in series between a common node of the first inductor and the first switch and a common node of the second switch and the second inductor. The output circuit generates an AC output voltage based on the DC intermediate voltage across the capacitor.

Abstract: A boost converter includes a first inductor, a first switch element, a second switch element, a tuning circuit, and an output stage circuit. A first parasitic capacitor is built in the first switch element. The first switch element selectively couples the first inductor to a ground voltage according to a first control voltage. A second parasitic capacitor is built in the second switch element. The second switch element selectively couples the first inductor to the output stage circuit according to a second control voltage. The tuning circuit includes a second inductor, a third inductor, and a discharge path. The first parasitic capacitor resonates with the second inductor and is coupled through the discharge path to the ground voltage, or the second parasitic capacitor resonates with the third inductor and is coupled through the discharge path to the ground voltage.

Abstract: The invention provides a control circuit for controlling the operation of a power converter having a switch connected to an output of the power converter, said control circuit comprising a first amplifier for sensing an output voltage of the power converter and a second amplifier configured to derive a frequency compensated error signal output, to provide a frequency control compensation loop to an input of the power converter and the output of the second amplifier is connected to the switch of the power converter.

Abstract: Aspects of the present disclosure provide addressable detection and alarm systems and methods for controlling a combined circuit by a control panel. In an example, a combined circuit may include one or more addressable initiating devices and one or more non-addressable notification appliances communicatively coupled with paired wires in parallel. The control panel may receive, on the paired wires, an indication of an anomaly from an addressable initiating device and transmit, on the paired wires, the alarm signal to the one or more addressable initiating devices and the one or more non-addressable notification appliances, wherein a first state of the alarm signal activates the one or more non-addressable notification appliances and deactivates the one or more addressable initiating devices, and wherein a second state of the alarm signal deactivates the one or more non-addressable notification appliances and activates the one or more addressable initiating devices.

Abstract: A method includes providing a transformer with primary and current injection windings, a primary switch connected to the primary winding, a parasitic capacitance reflected across the primary switch, a secondary rectifier means, and a current injection circuit including a current injection switch connected to the current injection winding, and a unidirectional current injection switch connected to the current injection winding. The method includes switching on the current injection switch to start a current injection flowing from a controlled voltage source, through the unidirectional current injection switch and further through the current injection winding. The current injection reflects into the primary winding, thereby discharging the parasitic capacitance reflected across the primary switch. The method includes turning on the primary switch with a delay time after the current injection switch turns on and turning off the current injection switch after the current injection reaches zero amplitude.

Abstract: The disclosed embodiments provide a system that manages use of a battery in a portable electronic device. During operation, the system operates a charging circuit for converting an input voltage from a power source into a set of output voltages for charging the battery and powering a low-voltage subsystem and a high-voltage subsystem in the portable electronic device. Upon detecting the input voltage from the power source and a low-voltage state in the battery during operation of the charging circuit, the system uses a first inductor group in the charging circuit to down-convert the input voltage to a target voltage of the battery that is lower than a voltage requirement of the high-voltage subsystem. The system also uses a second inductor group in the charging circuit to up-convert the target voltage to power the high-voltage subsystem.

Abstract: In some examples, a system includes a battery, a first voltage regulator with an input, and a second voltage regulator with an input. The input of the second voltage regulator is shifted in phase relative to the input of the first voltage regulator.

Abstract: A charger circuit with temperature compensation function includes: a power converter, an input voltage sense circuit, an output adjustment circuit and a charging control circuit. The power converter converts an input voltage supplied from a photovoltaic power module to an output voltage. The input voltage sense circuit generates a signal related to the input voltage according to the input voltage. The output adjustment circuit generates an output adjustment signal according to the signal related to the input voltage. The charging control circuit generates a control signal according to the output adjustment signal, thereby adjusting a level of an output current supplied from the power converter. When a level of the input voltage is smaller than a predetermined voltage threshold, the power converter decreases the output current.

Abstract: An adaptive frequency adjusting system is provided. An error amplifier outputs an error amplified signal according to an output voltage of a power converter and a reference voltage. When a comparator determines that a voltage of a slope signal reaches a voltage of the error amplified signal within a maximum on-time of an upper bridge switch, the comparator outputs a reset signal. When the comparator determines that the voltage of the slope signal fails to reach the voltage of the error amplified signal and the maximum on-time ends, the comparator outputs the reset signal and instructs a clock generator to output a clock signal having a lower frequency. A driver circuit turns off the upper bridge switch and turns on a lower bridge switch according to the reset signal, and drives the upper bridge switch based on the clock signal having the lower frequency.

Abstract: A power factor correction circuit with burst setting includes a conversion circuit, a control unit, and a burst setting circuit. The burst setting circuit respectively sets at least one burst period when an input power source is at a rising edge of a positive half cycle, a falling edge of the positive half cycle, the rising edge of a negative half cycle, and the falling edge of the negative half cycle, and provides a burst setting signal corresponding to the at least one burst period to the control unit so that the control unit limits the conversion circuit to perform a burst operation during the at least one burst period.

Abstract: A signal amplifier for use in a power converter includes a variable reference generator coupled to generate a reference signal in response to a dimming control signal. A variable gain circuit is coupled to receive the reference signal, the gain signal, and a feedback signal representative of an output of the power converter. The variable gain circuit is coupled to output a first adjusted signal in response to the reference signal and the gain signal. The variable gain circuit is coupled to output a second adjusted signal in response to the feedback signal and the gain signal. An auxiliary amplifier is coupled to output the gain signal in response to the first adjusted signal and a set signal.

Abstract: A method of controlling discharge of a holdup capacitor in a power system having a voltage source, a holdup capacitor and a load. The method including operably connecting the voltage source to the load, monitoring a first voltage of the voltage source, and if the first voltage of the voltage source drops below a selected threshold, directing energy from the holdup capacitor to the load via a first path, and directing energy from the holdup capacitor to the load via a second path if a selected condition is satisfied.

Abstract: Aspects of the present disclosure provide non-addressable detection and alarm systems and methods for controlling a combined circuit by a control panel. In an example, a combined circuit may include paired wires, one or more initiating devices, and one or more notification appliances communicatively coupled with the paired wires in parallel. The control panel may monitor the one or more initiating devices in a standby mode while maintaining the one or more notification appliances in an off state. When the control panel detects an anomaly from one or more initiating devices, the control panel may switch the combined circuit to an alarm mode. In the alarm mode, the control panel may activate the one or more notification appliances and maintain the one or more initiating devices in an off state.