Abstract: This power supply device includes a series circuit of a first switching element and a second switching element connected in parallel with a DC power supply unit, and a smoothing filter circuit which includes a series circuit of an inductor and a smoothing capacitor connected in parallel with the second switching element. The power supply device also includes a control unit and a drive circuit for generating first and second PWM pulses by respectively driving the first and second switching elements ON and OFF, and for creating a dead time between those switching pulse signals. And this control unit changes the frequency of the switching pulse signal according to the pulse width of either the first PWM pulses or the second PWM pulses.

Abstract: A USB charger circuit includes at least a converter, a control circuitry, a first resistor, a second resistor, an error amplifier, a sense resistor and a diode. The converter has a transistor. The control circuitry is coupled to the transistor. The control circuitry is used for producing a drive signal to the transistor. The first resistor is connected between the output node of the converter and a first node. The second resistor is connected between the first node and a second node. The error amplifier is coupled to receive a voltage divided by the first resistor and the second resistor to compare to a reference voltage. The sense resistor is connected between the second node and ground. The diode is connected between the output node of the converter and a first node.

Abstract: An energy harvesting circuit harvests energy from a voltage source and charges a storage element with the harvested energy. The energy harvesting circuit includes an energy source, a storage capacitor to store energy output from the energy source, a power converter circuit, an energy storage element, and an enabling circuit. The enabling circuit turns the boost converter circuit on and off according to a monitored capacitance voltage of the storage capacitor. When the boost converter circuit is turned off, the storage capacitor accumulates energy output from the energy source until a reference voltage is reached, whereupon the boost converter circuit is turned on, enabling current flow from the storage capacitor to the storage element. When the storage capacitor discharges to a minimum voltage level, the boost converter circuit is turned off. The enabling circuit and a reference voltage supply are powered by the energy source.

Abstract: A system for automatic disconnect of an AC source from a converter that includes a converter and a converter. The converter includes a power supply capable of being connected to an alternating current (AC) power source and converting an AC voltage to a direct current (DC) voltage. The portable device contains a rechargeable battery where the portable device uses the DC voltage to charge the rechargeable battery. The connection of the converter to the AC power source is automatically disconnected responsive to the rechargeable battery reaching a full charge or the portable device being disconnected from the converter and automatically reconnected responsive to the rechargeable battery being below a full charge or the portable device being reconnected to the converter.

Abstract: An apparatus comprises a first energy storage device configured to output a DC voltage, a first bi-directional voltage modification assembly coupled to the first energy storage device, and a charge bus coupled to the first energy storage device and to the first bi-directional voltage modification assembly. The apparatus also comprises high-impedance voltage source coupleable to the charge bus and a controller configured to monitor a transfer of charging energy supplied from the high-impedance voltage source to the first energy storage device. The controller is also configured to compare the monitored transfer of charging energy with a threshold value and, after the threshold value has been crossed, control the first bi-directional voltage modification assembly to modify one of a voltage and a current of the charging energy supplied to the first energy storage device.

Abstract: A contactless charging device and contactless charging method is provided. The contactless charging device includes an energy-storing device for providing a DC signal as an input power, a power module electrically connected to the energy-storing device for generating an output signal in response to the DC signal and a control signal. The power module includes a transformer primary winding for coupling the output signal to a transformer secondary winding located external to the contactless charging device. The charging device further includes a feedback controller electrically connected to the power module for generating the control signal in response to the output signal, a predetermined power and a predetermined phase. When the contactless charging device is in close proximity to a plurality of loads, the output signal at the transformer primary winding will be coupled to the transformer secondary windings of the plurality of loads so as to simultaneously charge the loads.

Abstract: In a control apparatus for an electric car, wherein an auxiliary power source device, a drive control device and a power storage system are connected in parallel; the power storage system is configured of a DC-DC converter in parallel with which a capacitor is connected, a power storage portion, and a power storage system control portion which performs the controls of the DC-DC converter and the power storage portion, and the power storage system control portion is configured so as to be capable of detecting the service interruption and grounding of an overhead line.

Abstract: Voltage conversion and charging circuitry and method for converting an alternating current (AC) voltage to a direct current (DC) voltage for charging an energy storage element (e.g., battery or supercapacitor). An output capacitance, which is initially charged quickly for use in the slower charging of a battery, also maintains the charge on an input capacitance which provides power for the charging control circuitry during such charging process. In accordance with a preferred embodiment, the DC charging current is substantially constant during a first time interval following which the DC charging power is substantially constant during a second time interval.

Abstract: A battery charger includes one or more channels for independently charging one or more batteries at different current levels. The battery charger also includes multiple modes for each channel for charging a battery with a continuous current or a pulse current. The battery charger supplies charging current by holding the charging voltage at a set value.

Abstract: The present invention provides a voltage converter circuit for the clocked supplying of energy to an energy storage, based on an input voltage present at an input of the voltage converter circuit. The voltage converter circuit comprises an energy storage and a switch assembly, the switch assembly comprising a first switch and a second switch connected in parallel and coupled to the energy storage. The first switch of the switch assembly exhibits, according to magnitude, a smaller turn-on voltage than the second switch, wherein a control terminal of the first switch is switched such that the first switch is active in a starting phase of the voltage converter circuit in order to supply the energy storage with energy, and wherein a control terminal of the second switch is switched such that the second switch is active after the starting phase in order to supply the energy storage with energy in a clocked manner.

Abstract: A photovoltaic system, method and apparatus are disclosed. In an exemplary embodiment, the system includes a first and second inputs adapted to couple to a first and second rails of a photovoltaic array; an inverter configured to convert DC power from the photovoltaic array to AC power; and an interface portion coupled to the first and second inputs and the inverter, the interface portion configured to isolate at least one of the first and second inputs from the inverter and to modulate an application of a voltage from the photovoltaic array to the inverter so as to increase a load on the photovoltaic array and to reduce the voltage applied from the photovoltaic array to the inverter.

Abstract: A battery that includes an electrochemical cell having an internal bore therethrough is described herein. The battery also includes a voltage converter module electrically coupled to the electrochemical cell and disposed within a portion of the internal bore The voltage converter is configured to convert a first voltage produced by the electrochemical cell into a second, different voltage.

Abstract: In a method for controlling a generation of an alternating current in a vehicle equipped with a battery and an inverter, the inverter is electrically connectable to the battery in order to generate an alternating current from a direct current of the battery for electrical devices that are electrically connectable to the inverter, and the battery is recharged when a charging state of the battery is equal to or less than a threshold value that is sufficient to generate an alternating current required for the electrical devices.

Abstract: Transient processing mechanisms for power converters. Error generation circuitry in a power converter may generate an error signal based on the difference between a power converter output voltage and a reference voltage. Transient detection circuitry may detect whether the error signal exceeds at least a first threshold. If the first threshold is exceeded, timing control logic may generate a low band correction pulse to adjust the power converter output voltage, and thereby adjust the error signal to a level within the first threshold. If the error signal exceeds a second threshold, the timing control logic may generate a high band correction pulse to adjust the power converter output voltage, and thereby adjust the error signal to a level within the second threshold. The timing control logic may initiate a low band blanking period following the low band correction pulse and high band blanking period following the high band correction pulse.

Abstract: An imaging apparatus including a strobe device having a charging circuit of a separately excited oscillation type is provided. The apparatus includes a main capacitor in which charge is accumulated to supply power to a strobe-light-flashing unit, a step-up transformer including at least primary and secondary coils, a switching element that performs a switching operation to control a current supplied to the primary coil, a rectifier diode that rectifies a flyback pulse generated in the secondary coil to supply a charging voltage to the main capacitor, a power-supply-interrupting circuit that selectively interrupts power supplied from the power supply, a full-charge detection unit that detects whether the main capacitor reaches a fully charged state, and a power-supply-control unit that controls the power-supply-interrupting circuit so as to set the power-supply-interrupting circuit to be in an interrupting state.

Abstract: The present invention provides a solar cell that can be utilized as a stable electric power source for cloudy weather. An output voltage V1 of the solar cell 1 is lowered by a DC-DC converter 5. When a battery V2 is charged with an output of the converter 5, the converter 5 is stopped and the power of only the battery V2 is supplied to a low-voltage inverter circuit 6. The electric power supplied from the converter 5 is increased by boosting the output voltage of the converter 5 as well as starting to supply electric power from the battery V2. While the electric power of the converter 5 is increased, the performance of the solar cell 1 is judged. When the performance is decreased, the output voltage from the converter 5 is lowered and the amount of electric power supplied from the battery 2 is increased relatively.

Abstract: An energy capture circuit for capturing energy in response to an input pulse. The circuit is constructed and arranged to transfer input energy in time divided portions among subcircuits. This includes a storage means, a clock means, at least two subcircuits, and at least one transfer circuit. Each subcircuit includes a first inductive means in operative communication with the input source, a rectifying means for producing a positive current in operative communication with the first inductive means, a capacitive means in operative communication with the rectifying means, and a switch means in operative communication with the capacitive means. At least one transfer circuit is in operative communication with each of the switch means of the at least two subcircuits. The output of the clock means is in operative communication with both a first switch means and an inverter means, the inverter means having an output in operative communication with a second switch means.

Abstract: In a DC-DC converter using, as an input source, a fuel cell, a solar cell, or the like, having a relatively large output impedance in a power-supply mode, an arbitrary load and secondary battery based on magnetic coupling in which voltage values are determined by a turns ratio between those wound around a winding, are provided as outputs, a second converter is connected between an output of the secondary battery and the load. In addition, a current control circuit connected to the secondary battery is configured to perform control so that, when a current in the load decreases due to an operation of the magnetic coupling, by increasing a charging current which flows into the secondary battery, and, when the current in the load increases, by decreasing the charging current to the secondary battery, an output voltage of the secondary battery is maintained at a set drooping voltage.

Abstract: A DC-DC converter includes an inductor, a capacitor, an output voltage detection circuit, and a synchronous rectification circuit including a rectifier-side synchronous rectifier element and a commutator-side synchronous rectifier element. The commutator-side synchronous rectifier element is turned on so as to pass a current through a closed loop composed of the commutator-side synchronous rectifier element, the inductor, and a second secondary battery. The characteristic evaluation of the second secondary battery is performed on the basis of the decrease in a detection voltage Vout of an output voltage Vo. As a result, it is possible to determine the effective capacity or characteristic degradation state of the second secondary battery with a circuit to charge the second secondary battery without using a dedicated circuit.

Abstract: Embodiments of the present invention include techniques for charging a battery. In one embodiment, the present invention includes a method comprising determining if a maximum current output of a power source is above a threshold, configuring a regulator coupled to the power source, wherein the regulator is configured in a pass mode if the maximum current output is above the threshold, and wherein the regulator is configured in a regulation mode if the maximum current output is below the threshold, and generating pulses to a battery, wherein an output of the regulator is coupled to the battery when a pulse is being generated, and the output of the regulator is decoupled from the battery when a pulse is not being generated. In other embodiments, the techniques may be embodied in a circuit including a detection circuit and a switching regulator coupled to a battery through a pulse circuit.

Abstract: A power supply circuit includes a first power supply configured to output a first voltage; a second power supply provided separately from the first power supply to output a second voltage; and a boosting circuit configured to use the first voltage as an input voltage to boost the input voltage toward a target voltage. The target voltage has a voltage width, and when an output voltage of the boosting circuit exceeds an upper limit of the target voltage, the input voltage is switched the first voltage of the first power supply to the second voltage of the second power supply.

Abstract: An apparatus for switching from a first power supply to a second power supply. Such an apparatus may determine which of the first and second power supplies has a greater voltage, and may power a device from the power supply having the greater voltage or charge. A single boost converter may be used regardless of which power supply is providing power.

Abstract: Disclosed is a power adapter having a voltage limiting circuit for limiting an output voltage of the power adapter at a predetermined voltage level when an output current of the power adapter is smaller than a threshold current, and a power limiting circuit for limiting an output power of the power adapter at a predetermined power level when an output current of the power adapter reaches the threshold current, in which the voltage limiting circuit can be configured to receive a current control signal from a load and in response thereto issue a load current regulation signal to a switching control circuit of the power adapter, thereby regulating the output voltage of the power adapter based on the load current regulation signal.

Abstract: A high frequency battery charger includes a converter, drive logic, and control logic. The converter transforms a DC voltage into a high frequency AC voltage. The drive logic controls a conversion of the high frequency AC voltage through a train of pulses. The control logic adjusts the output of the converter to maximize a charging cycle of a battery. The method of transforming an AC input into a direct current output used to charge a rechargeable battery includes transforming an AC input into a first DC output; transforming the first DC output into a high frequency AC output; transforming the high frequency AC output into a second DC output; and passing a charging current to an external load when the load is correctly connected to an output.

Abstract: A magnetic motor system includes a brushless motor with interdigitated permanent magnets longitudinally mounted on a rotor at equal radial positions, and stator windings to drive the rotor in response to pulses from a timer/driver, and stationary recapture windings to recover energy that would otherwise go to waste. One set of batteries is used to drive the motor through the timer/driver, and bridge rectifiers connected to the stationary recapture windings provide electrical current to charge a second set of batteries. The rotor shaft output provides kinetic energy to drive electrical generators, air compressors, etc. A shaft encoder connected to the rotor provides the information needed by the timer/driver to know which stator winding should be pulsed and with what polarity. A power pulse is provided at least every 12.5 degrees of rotation, making the motor self starting.

Abstract: The invention provides a bidirectional converter that operates under an AC generation mode or a charge mode. The bidirectional converter may be a single component or circuit, which may include a DC-DC conversion stage using a unique “Smith 2 Stage conversion” technique and a DC-AC conversion stage or AC-DC conversion stage using a switchable filter depending on the mode. During the charge mode, the converter may be able to control the voltage and current of the DC output using a software algorithm, to match the battery being charged, or the DC receiver. This may enable the converter to control the nature of the DC output so it can be adapted to any energy storage technology. The controllable output voltage and synchronizable frequency may allow the converter to be used in series combinations to achieve a variety of high voltage outputs from simpler building blocks.

Abstract: In one embodiment, a battery management system includes a charger controller for controlling a charging current of a battery according to a status of a load which is powered by the battery, and a counter coupled to the charger controller for determining a charging time according to such status. Advantageously, a first charging current is selected when the load is off. A second charging current that is less than the first charging current is selected when the load is on. Furthermore, a frequency of the counter is set to a first frequency when the load is off. The frequency is set to a second frequency that is less than the first frequency when the load is on.

Abstract: A power storage system regulates DC power from a DC power supply into prescribed voltage and current using a DC-DC converter unit for storage in a storage unit. On the DC power supply side of the DC-DC converter, the system includes a primary side current detecting unit, a primary side voltage detecting unit, a primary side switch unit, and a primary side filter unit. On the storage unit side of the DC-DC converter, the system includes a secondary side filter unit, a secondary side switch unit, a secondary side voltage detecting unit, and a secondary side current detecting unit. The on/off states of the primary and secondary side switch units, and the DC-DC converter unit are controlled by a system control unit provided with an externally applied operation command and signals obtained from elements such as the primary side current detecting unit and the primary side voltage detecting unit.

Abstract: A power pack system for charging a set of isolated batteries is provided. In an illustrative embodiment of the invention, a single fuel cell, a single DC-DC converter and a single system controller device comprises the power-generation side of the power pack. A set of switches is used to connect the power-generation side of the Power pack to one of the isolated batteries in the power pack, thereby recharging that particular battery in the battery power pack set. A battery protection and powerpath control device communicates with the system controller to determine which switches are to be closed depending upon which battery requires recharging. During normal operation the switches will follow the direction from the system controller. If a fault is detected by the battery protection circuit, the protection circuit will take priority and turn off the appropriate switch(es).

Abstract: A portable electrical device may include a DC to DC converter coupled to a common node, a load coupled to the common node, and a controller configured to control the DC to DC converter. The DC to DC converter may be configured to provide a charging current to a rechargeable battery from an adapter when the controller operates said DC to DC converter in a first adapter supply mode. The DC to DC converter may be configured to provide a battery supply current to the load via the common node when the controller operates the DC to DC converter in a second adapter supply mode. The adapter supply current and the battery supply current may add together at the common node to simultaneously provide a load supply current to the load in the second adapter supply mode.

Abstract: A DC-DC converter for generating a stable output voltage and being applicable to a transient load fluctuation. The DC-DC converter detects an input current, and compares the input current with a rated current of an external power supply. The DC-DC converter controls a positive charging current that is supplied to a secondary battery in accordance with a consumption current of a load so that the input current does not exceed the rated current. The DC-DC converter further controls a negative charging current that is supplied from the secondary battery to the load when the load requires an input current exceeding the rated current.

Abstract: A controller IC adjusts the on time and cycle time of current flowing through the primary inductor of a flyback converter to generate a constant output current and constant output voltage. A desired output current limit is achieved even with an inductor whose inductance varies from the stated magnitude. A transconductance current is generated from a voltage across an emitter resistor and is then integrated to generate an integrated-current voltage. An inductor switch is turned on by an oscillator signal and turned off at the earlier of when the integrated-current voltage reaches a charge limit voltage during constant current mode or when the emitter resistor voltage reaches an error voltage during constant voltage mode. Current is output independently of the primary inductance by varying the current limit voltage inversely proportionally to the input voltage and by adjusting the cycle time so that it varies inversely proportionally to the output voltage.

Abstract: Apparatuses, systems, and methods for providing battery-backed power to movable partitions are disclosed. A power converter generates a DC output from an AC input. The DC output may be selectively decoupled from an enabled DC output such that the DC output can be monitored for acceptable operation in-situ. The enabled DC output may be selectively coupled to a battery output terminal. A charge current may be sensed between the enabled DC output and the battery output to control charging of the battery with a pulse-width modulation operation by controlling the selective coupling of the enabled DC output to the battery output. The enabled DC output and the battery output are coupled in a logical-OR configuration to generate a supply output providing current from the enabled DC output and the battery. The supply output may drive a movable partition controller and a motor configured for opening and closing a movable partition.

Abstract: In a capacitor charger including a transformer having a primary winding connected with an input voltage and a secondary winding for transforming a primary current flowing through the primary winding to a secondary current flowing through the secondary winding, the primary current is adjusted according to a monitoring voltage varying with the input voltage, thereby prolonging the lifetime of the battery that provides the input voltage and improving the power efficiency of the battery.

Abstract: Exemplary methods and systems for charging a battery in a power management unit include a power regulator having an input power supply and a processor that regulates a charging rate of the battery based on measured parameters of the power regulator and the battery. The processor is programmed to perform exemplary methods that include receiving an output voltage signal and a battery temperature signal from the power regulator, and comparing the output voltage to a first threshold to determine a charge level of the battery. An exemplary method includes selecting a charging mode based on the comparison, and sending a first control signal to the power regulator to adjust a charging rate of the battery based on the battery temperature.

Abstract: An electric-motor controller uses multiple semiconductor switches in parallel, arranged so as to improve turn-on and turn-off synchronization. A physical “sandwich” arrangement improves manufacturability of some embodiments. A system using the controller can recharge a battery pack from a charging source of a different voltage by using a field coil of the motor as an inductor in a step-up or step-down circuit. Controller software monitors parameters such as battery voltage, temperature and current to adjust system operation.

Abstract: An apparatus for switching from a first power supply to a second power supply. Such an apparatus may determine which of the first and second power supplies has a greater voltage, and may power a device from the power supply having the greater voltage or charge. A single boost converter may be used regardless of which power supply is providing power.

Abstract: The present invention discloses a transformer used in a charger circuit, in which the input side of the transformer is connected to an AC input and PWM control circuit of the charger circuit, the output side of the transformer is connected to a constant current and/or constant voltage control circuit of the charger circuit. The AC input, PWM control circuit, the constant current and/or constant voltage control circuit are coupled through an optical coupling element, wherein the transformer includes a main output winding and an auxiliary output winding, and the auxiliary output winding is used to supply power for the optical coupling element and the constant current and/or constant voltage control circuit. The present invention further provides a high performance charger circuit adopting the transformer described above for improving electromagnetic compatibility, conversion efficiency and short circuit characteristic.

Abstract: In a capacitor charger including a transformer having a primary winding connected with an input voltage and a secondary winding for transforming a primary current flowing through the primary winding to a secondary current flowing through the secondary winding, the primary current is adjusted according to a monitoring voltage varying with the input voltage, thereby prolonging the lifetime of the battery that provides the input voltage and improving the power efficiency of the battery.

Abstract: An apparatus for switching from a first power supply to a second power supply. The embodiment may detect the charge or voltage of both the first and second power supply, and power a device from the power supply having the greatest voltage or charge. A single boost converter is used regardless of which power supply is providing power.

Abstract: An over voltage transient controller to protect a rechargeable battery from an over voltage transient condition. The over voltage transient controller may comprise a comparator to compare a first signal with a second signal representative of a reference voltage level and to provide an output signal representative of an over voltage transient condition to a switch if the first signal is greater than or equal to the second signal. The switch is responsive to the output signal to protect the rechargeable battery from the over voltage transient condition. The over voltage transient controller may further comprise a DAC, wherein the second signal is based, at least in part, on an output of the DAC. An apparatus comprising a charge switch and such an over voltage transient controller is also provided.

Abstract: A battery-operated portable electronic device has a primary battery to provide energy to low current circuitry of the portable device, and a supplemental battery to provide intermittent bursts of energy to other components of the portable device. A charging device charges the supplemental battery from the primary battery. An electronic device employing the battery system may have a battery compartment for the primary battery, which can be an AAA, AA, C, or D size battery.

Abstract: A voltage regulation and battery charging system is provided. The system may include a switching regulator selection control circuit, two switching regulator controller circuits, two power transistors, a common synchronous transistor, a common LC circuit, and a battery charger circuit. The two switching regulator controller circuits may synchronously switch the two power transistors and the one common synchronous transistor. One of the switching regulator controller circuits may receive voltage from an AC adapter and the other may receive voltage from the battery. The first switching regulator controller circuit is employed to provide system power when the AC adapter is connected. When the battery is used to provide the system power, the second switching regulator controller circuit is used to down-convert the battery voltage to provide the system power.

Abstract: A method for charging a battery at a battery charger comprising connection means for connection to the terminals of a battery to be charged, means for detecting a voltage over the terminals of a connected battery, and control means. The method comprises the steps of initiating a burst cycle, wherein a plurality of consecutive voltage burst are applied to a connected battery to be charged, each burst successively lowering the internal resistance of the battery and initiating a charging cycle to charge the connected battery when said burst cycle has been terminated. Furthermore, a method for maintenance charging a battery at a battery charger including detecting a voltage over the connected battery; maintaining the voltage over the battery at a predetermined level for a predetermined period of time; monitoring a battery capacity parameter when said predetermined period of time has elapsed; and applying at least one voltage pulse if said parameter falls below a predetermined threshold level.

Abstract: This invention relates to a power module for a plug-in hybrid electric vehicle including an integrated converter having a rectifier changing AC to DC, a DC/DC converter changing from a first voltage to a second voltage, and a battery storing electrical energy. The integrated converter operates in three modes 1) AC plug-in charging mode, 2) boost mode supplying power from the battery to the electrical bus and 3) buck mode supplying power from the electrical bus to the battery. The integrated converter utilizes the same single inductor during each of the three operating modes to reduce cost and weight of the system.

Abstract: A new charger wherein a reference voltage can be set therein. The charger charges a secondary battery via a DC/DC converter that has an arrangement in which a fuel cell, a solar cell or the like having a relatively large output impedance during power supply is used as an input source (Vfc) and an input power is kept constant. The secondary battery (B) is connected to a control circuit (10), and a constant power reference voltage control circuit (20) is connected between the current control circuit and an input of the charger. When the output of the charger is drooping, the constant power reference voltage control circuit reduces the reference voltage to increase the power to be supplied, thereby providing a constant power at the voltage as defined by the output voltage stabilization control of the charger. When the input power of the charger is excessive, the constant power reference voltage control circuit increases the reference voltage to set a reference value corresponding to the power to be supplied.

Abstract: A charging method and device for a rechargeable battery to make more stable and faster full charging possible. One embodiment of a charging method for the rechargeable battery includes charging the battery by applying a constant current, and then charging the battery by applying a constant current pulse having uniform pulse width. The charging method further includes charging the battery by applying or interrupting the constant current and then applying the dynamic constant current pulse based on a voltage across terminals of the battery.

Abstract: A voltage converter including a buck converter and a capacitive voltage divider. The converter includes four capacitors, a switch circuit, an inductor and a controller. A first capacitor is coupled between a reference node and a first output node which develops a first output voltage. A second capacitor is coupled between an input node and either the reference node or the first output node. The switch circuit couples a third capacitor between the reference and first output nodes in a first state of a PWM signal, and couples the third capacitor between the first output and input nodes in a second PWM signal state. The inductor is coupled to the third capacitor and provides a second output node coupled to the fourth capacitor providing a second output voltage. The controller controls the duty cycle of the PWM signal to regulate the second output voltage to a predetermined level.

Abstract: A charger capable of safely charging an apparatus even when the current limit value of an external power supply is less than the maximum charging current of the charger or when the battery voltage is low. Charger 100 has backup charging circuit 160 that performs charging using a current that is less than the charging current of charging control section 120. Control circuit 170 performs control so that charging control circuit 123 of charging control section 120 fixes charging control transistor 121 to OFF, makes backup charging circuit 160 operate, and performs backup charging using minute current Ichsub when battery voltage Vb is lower than predetermined value Vbx1, and fixes control transistor 111 of DC/DC converter 110 to ON when supply voltage Vc is less than a first supply voltage value.

Abstract: The present invention provides an apparatus for controlling a capacitor charging circuit and a method thereof. The apparatus includes a first comparator, a second comparator, and a controller. The first comparator, which is coupled to the charging circuit, receives a voltage level and compares the voltage level with a reference voltage level to generate a first indication signal. The voltage level corresponds to an output voltage of the charging circuit. The second comparator receives a control value and compares the control value with a threshold value to generate a second indication signal. The controller, which is coupled to the charging circuit, the first comparator and the second comparator, generates a control signal according to the first indication signal and the second indication signal to turn the charging circuit on and off, and further generates the control value according to the control signal.