Patent application number | Description | Published |
20090184698 | Switching power supply - A switching power supply exhibits high conversion efficiency and facilitates reducing the size thereof. The switching power supply includes a half-bridge circuit including a first series circuit formed of switching devices Q | 07-23-2009 |
20090237050 | Switching power supply - A switching power supply, which operates intermittently under a light load for suppressing electric power consumption, reduces output voltage variations caused when a load current increases rapidly from a light load state, and reduces output voltage ringing. The switching power supply includes a comparator that compares a feedback signal obtained by isolating the output from an error amplifier with a burst threshold value and a comparator that compares the feedback signal with a power-supply-interruption threshold value preset to be lower than the burst threshold value. The switching power supply stops output of a driving pulse from a driver circuit when the feedback signal is lower than the burst threshold value. The switching power supply also stops the output of operation power from first power supply circuit when the feedback signal is lower than the power-supply-interruption threshold value. | 09-24-2009 |
20090244943 | Power Converter - A power converter includes a small-sized inductor connected to an AC voltage input line for power factor correction and a filter for suppressing conduction noise. The inductor is connected to a rectifier and comprises first and second windings and that are wound on a common magnetic core and loosely coupled with each other. A leakage inductance component of the inductor functions as an energy storage element in a main conversion operation and an excitation inductance component of the inductor functions as a noise reduction element for suppressing an conduction noise caused by on-off operation of a switching element. | 10-01-2009 |
20090284991 | Switching power supply - A switching power supply includes a control circuit controlling ON and OFF of switching devices Q | 11-19-2009 |
20100110739 | Control system of a power factor correction circuit - A control system for a power factor correction circuit performs stabilized oscillation operation and suppresses switching frequency variation due to change of the AC power source. A control system includes a voltage error amplifier for outputting a voltage error signal obtained by amplifying a difference between a DC output voltage Vo and a command value Vref of the DC output voltage, a current command value generating circuit for outputting a current command value Vi for controlling the input current Iin, a comparator comparing an inductor current signal obtained by detecting an inductor current running in the switching element by a current detecting resistor with a magnitude of the output signal Vi from the multiplier, a timer circuit for setting an off-period of the switching element corresponding to the voltage Vd, and a reset-set type flip-flop circuit for setting an off-timing of the switching element after an elapse of the off-period. | 05-06-2010 |
20100309699 | POWER FACTOR CORRECTION CIRCUIT - A power factor correction circuit includes a filter capacitor interposed between AC input terminals, a first inductor interposed between the first end of the filter capacitor and an input of a first rectifying bridge circuit, and a second inductor interposed between the second end of the filter capacitor and another input of the first rectifying bridge circuit. The power factor correction circuit further includes a second rectifying bridge circuit including inputs connected to AC input terminals, and outputs connected to a smoothing capacitor. A control circuit controls switching devices in the first rectifying bridge circuit. The power factor correction circuit can facilitate preventing an overcurrent from flowing through diodes and parasitic diodes in the switching devices, using a simple configuration. | 12-09-2010 |
20120313646 | CURRENT ESTIMATION CIRCUIT - To provide a current estimation circuit that can achieve a reduction in cost, a miniaturization, and a suppression of switching loss, and estimate an inductor current with a high degree of accuracy, despite a variation in the inductance value of the inductor. A current flowing through a switching element ( | 12-13-2012 |
20130141946 | SWITCHING POWER SUPPLY DEVICE AND METHOD FOR CONTROL THEREOF - A switching power supply device and method for control thereof, including an input voltage generating unit, a transformer, an output voltage generating unit, a MOS transistor, an output voltage detecting unit, a switching control unit, and a power supply unit. The output voltage detecting unit detects a transformer tertiary winding voltage, compares it with a first reference value, compares the differentiated tertiary winding voltage with a second reference value, and determines the start and end of a detection period based on the two comparisons. The output voltage detecting unit also samples and holds the voltage with two sampling pulses within the detection period, selects one of the two sampled and held voltages, and outputs the selected voltage when the detection period ends. | 06-06-2013 |
20140104890 | BI-DIRECTIONAL DC/DC CONVERTER - A bi-directional DC/DC converter comprises bridge circuits connected to DC voltage sources, an isolation transformer, an LC resonance circuit, and detection circuits for detecting voltages and currents of the DC voltage sources. A control circuit in the power flow from a first DC voltage source to a second DC voltage source changes over between fixed frequency control and frequency modulation control according to the magnitude of a control variable, and a control circuit in the power flow from a second DC voltage source to the first DC voltage source changes over between fixed frequency control and frequency modulation control according to the magnitude of another control variable. Thus, the bi-directional DC/DC converter can be applied to devices with a wide range of input and output voltages. | 04-17-2014 |