Patent application number | Description | Published |
20080278134 | SWITCHING POWER SUPPLY DEVICE - The present invention provides a switching power supply device including a switching element, a control circuit controlling the switching element, a transformer having an auxiliary winding, a potential clamp circuit connected to one of outputs of the transformer, a delay capacitor connected to an output of the potential clamp circuit, a potential detection circuit detecting a potential at the delay capacitor, and an overload protection actuation circuit realizing overload protection. During an overload, the delay capacitor is charged only by ringing of the auxiliary winding, generated immediately after the switching element is turned off, through the potential clamp circuit. Then, the potential detection circuit supplies an actuation signal to a latch stop circuit by detecting that the potential at the delay capacitor rises. The latch stop circuit latches and stops the switching operation of the switching element to realize the overload protection when the actuation signal is fed into the latch stop circuit. Thus, the overload protection can be realized with a sufficient delay time by the relatively small delay capacitor. | 11-13-2008 |
20090097284 | SWITCHING POWER SUPPLY - In the present invention, an on time is used which increases at an instantaneous interruption. The on time is detected by a MAX-DUTY detector | 04-16-2009 |
20090108818 | SWITCHING POWER SUPPLY CIRCUIT - According to the present invention, an auxiliary power supply | 04-30-2009 |
20090201705 | ENERGY CONVERTING APPARATUS, AND SEMICONDUCTOR DEVICE AND SWITCHING CONTROL METHOD USED THEREIN - The present invention reliably reduces output power during an overload, due to overload protection in which an on-time of a switching element | 08-13-2009 |
20100008106 | SWITCHING CONTROL CIRCUIT, SEMICONDUCTOR DEVICE AND SWITCHING POWER SOURCE APPARATUS - At the starting time and an overload time in which the output voltage of the switching power source apparatus is low, if an overcurrent state, in which the ON period of the switching device becomes short and a current not less than the current limit value of the switching device flows through the switching device, occurs, this overcurrent state is detected. The blanking period of a blanking pulse signal is made shorter than the blanking period that is obtained during steady operation, and the ON period of the switching device is made shorter. Hence, the device current flowing through the switching device can be made small in each pulse for the switching operation, and, at the same time, the device current is suppressed from increasing each time a pulse for the switching operation is generated. | 01-14-2010 |
20100039087 | SWITCHING POWER SUPPLY CIRCUIT - A switching power supply circuit according to an aspect of the present invention includes: a switch; a coil serving as an energy transmitting element; a capacitor serving as an output generation circuit that outputs, as an output voltage, the energy transmitted from the coil; an output voltage detection circuit which generates a detection signal according to the output voltage; a PNP transistor serving as a transmission circuit that outputs a transmission signal according to a value of the detection signal; a controller which controls the switch according to the transmission signal; and a diode serving as a rectifying element connected between the transmission circuit (PNP transistor) and the controller. | 02-18-2010 |
20100124081 | SWITCHING POWER SUPPLY - According to the present invention, when a secondary current on period T | 05-20-2010 |
20100309690 | SWITCHING POWER SUPPLY APPARATUS AND SEMICONDUCTOR DEVICE - The switching power supply apparatus according to the present invention includes: a transformer including a primary winding, a secondary winding, and an auxiliary winding; a switching device connected to the primary winding; an output voltage generation circuit which is connected to the secondary winding and generates an output voltage; an auxiliary power voltage generation circuit which is connected to the auxiliary winding and generates an auxiliary power voltage; and a control circuit which operates using the auxiliary power voltage and controls a driver circuit so that an intermittent oscillation is performed when the output voltage is higher than a first output voltage and controls a peak of a current flowing through a switching device is lower than a peak in a normal mode, when the auxiliary power voltage is lower than a first auxiliary power voltage in the intermittent oscillation. | 12-09-2010 |