Abstract: A driving method and a driving device using the same are disclosed. The driving method controls a pulse transformer. The secondary winding of the pulse transformer is electrically connected to a control device. Firstly, positive charging electrical energy is delivered to the primary winding, thereby charging the control device. Then, the control device is disconnected from the secondary winding while the primary winding is in a high-impedance state. Finally, negative discharging electrical energy is delivered to the primary winding and the control device is electrically connected to the secondary winding, thereby discharging the control device, and the primary winding is in a low-impedance state after the step of delivering the negative discharging electrical energy to the primary winding.

Abstract: A method for controlling a converter is disclosed. The converter includes a first switch and a second switch. The method includes: turning on then turning off the first switch for storing an energy in the converter; turning on then turning off the second switch for transferring the stored energy in the converter; and turning on the second switch again thereby injecting the energy into the converter, and then turning off the second switch to increase levels of oscillations.

Abstract: An isolated switching mode power supply and a control method of the isolated switching mode power supply are provided. The isolated switching mode power supply includes a primary side circuit and a secondary side circuit. The primary side circuit includes a controller. The secondary side circuit is coupled to the primary side circuit and includes a winding, a switch, and an SR controller. The winding is coupled to the primary side circuit. The switch is coupled to the winding. The SR controller is coupled to the winding and the switch. The SR controller turns off the switch to trigger the winding to feed back a first message to the primary side circuit. The controller enables the primary side circuit to transfer energy to the secondary side circuit if the controller detects the first message.

Abstract: A method for modulating a voltage through a primary side regulating circuit and a secondary side regulating circuit, the method includes: providing a first controller in the primary side regulating circuit; providing a second controller in the secondary side regulating circuit; exchanging messages between the first controller and the second controller thereby alternately dominating a modulation of an output voltage between the primary side regulating circuit and the secondary side regulating circuit in accordance with the messages.

Abstract: The present disclosure provides an isolated power supply and a method of controlling the isolated power supply. The isolated power supply includes a primary side circuit and a secondary side circuit. The primary side circuit includes a first switch with a first voltage thereon, an auxiliary winding with a second voltage thereon, and a controller. The secondary side circuit includes a second switch and a pulse transformer. The method includes: retrieving the first voltage or the second voltage as a specific voltage; sensing an oscillation waveform of the specific voltage after the second switch is turned off at a first timing point in a first cycle; retrieving a second timing point based on the oscillation waveform; and controlling the pulse transformer to adaptively adjust a third timing point for turning off the second switch in a second cycle based on the second timing point retrieved in the first cycle.

Abstract: An information feedback system is disclosed. The information feedback system comprises a separating device having the primary winding and the secondary winding, a first electrical switch and a controller. The secondary winding is coupled to an operation device through the first electrical switch. The first electrical switch and the operation device are coupled to the controller. The energy is discharged from the secondary winding to the operation device through the first electrical switch. The operation device receives the energy from the first electrical switch to generate a plurality of commands. The controller receives the commands and uses the first electrical switch to encode a plurality of signals to generate encoded information according to the commands. The separating device transmits the encoded information from the secondary winding to the primary winding.

Abstract: A regulating power converter has a transformer, a charging circuit and a discharging circuit connected with each other. The charging circuit charges said transformer whereby the transformer generates a secondary voltage. The discharging circuit discharges the secondary voltage to generate an output voltage. The charging circuit retrieves time information from the secondary voltage through the transformer. The charging circuit drives the transformer to regulate the output voltage according to the time information.

Abstract: A method and a device for detecting conduction mode is disclosed. The method uses an energy-storing element to connect with a synchronous rectifier and a load, and the load connects with the synchronous rectifier. Firstly, energy is discharged from the energy-storing element and applied to the load through the synchronous rectifier to periodically generate a detected voltage signal across the synchronous rectifier, and the detected voltage signal comprises at least one raising waveform, at least one horizontal waveform and at least one descending waveform. Then, an output is generated according to waveform of the detected voltage signal and either of a reference duration or a reference slope, so as to determine that the energy-storing element operates in CCM or DCM.

Abstract: A valley-detection device for quasi-resonance switching and a method using the same is disclosed, which uses first and second capacitors to connect with a comparator, and the comparator connects with an NMOSFET connecting to a transformer. When the NMOSFET is turned off, the energy stored in the transformer is discharged and a resonant signal across the source and the drain is generated, and a first constant current charges the first capacitor at a start time point of the resonant signal until a voltage of the resonant signal first reaches to a crossing voltage. Then, a second constant current charges the second capacitor when the voltage of the resonant signal equals to the crossing voltage while the voltage of the resonant signal varies from high to low. Finally, the comparator turns on the NMOSFET when a voltage of the second capacitor equals to a voltage of the first capacitor.

Abstract: A maximize efficiency method for resonant converter with self-adjusting switching points is disclosed. The method is operated by a resonant converter, which comprises a transformer and a field effect transistor (FET). When the transistor is turned on, energy is stored in the transformer. When the transistor is turned off, a resonant signal is generated at a drain of the transistor. At this time, a suitable trigger time has to be found to turn on the transistor, so as to reduce switching power loss. The method measures the slope of the resonant signal at the trigger time. This is used as a reference to adjust the next cycle's trigger time. If the slope is negative at the time of trigger, a delta time is added to the trigger time in the next cycle, If the slope is positive, a delta time is subtracted from the trigger time for the next cycle.

Abstract: A maximize efficiency method for resonant converter with self-adjusting switching points is disclosed. The method is operated by a resonant converter, which comprises a transformer and a field effect transistor (FET). When the transistor is turned on, energy is stored in the transformer. When the transistor is turned off, a resonant signal is generated at a drain of the transistor. At this time, a suitable trigger time has to be found to turn on the transistor, so as to reduce switching power loss. The method measures the slope of the resonant signal at the trigger time. This is used as a reference to adjust the next cycle's trigger time. If the slope is negative at the time of trigger, a delta time is added to the trigger time in the next cycle, If the slope is positive, a delta time is subtracted from the trigger time for the next cycle.

Abstract: A method of power factor correction without using current sensing or a multiplier is disclosed. A generated predictive pulse is used to charge and discharge a power factor correction (PFC) inductor so that the current in the PFC inductor has a similar phase angle as the input AC voltage. Each ON portion of the pulse is used for charging while each OFF portion is used for discharging. As the input voltage increases in phase, the predictive pulse gradually increases in ON time duty and the PFC inductor is charged in increasing amount and discharged in decreasing amount per pulse. When peak is reached the duty ratio is reduced each pulse and the PFC inductor current is reduced along with the input AC voltage source until phase angle reaches 180 degrees and the ON time becomes zero.

Abstract: A method of power factor correction without using current sensing or a multiplier is disclosed. A generated predictive pulse is used to charge and discharge a PFC inductor in such a way that the current in the PFC inductor has a similar phase angle as the input AC voltage. Each ON portion of the pulse is used for charging while each OFF portion is used for discharging. As the input voltage increases in phase, the predictive pulse gradually increases in ON time duty and the PFC inductor is charged in increasing amount and discharged in decreasing amount per pulse. When peak is reached the duty ratio is reduced each pulse and the PFC inductor current is reduced along with the input AC voltage source until phase angle reaches 180 degrees and the ON time becomes zero.

Abstract: A PWM controller that effectively transitions between normal mode and green power mode is disclosed. A driver provides a normal drive signal during normal operation. A pulse width detector detects the pulse width of the PWM signal and if the pulse width drops below a threshold the normal mode drive signal will be turned off and a pulse ON time measurer will begin storing the pulse ON time. When the total ON time reaches a total ON time threshold or the output voltage drops below a voltage limit, a green mode drive signal will be output to the power converter. During green mode the driver will continue sending the green mode drive signal at intervals until a heavy load condition when the green mode drive signal will be shut off and the driver will resume sending the normal mode drive signal.