Abstract: A power supply is provided. The power supply comprises: a power input unit switching an input power; a transformer unit inducing an output power of the power input unit to a secondary side; a first power output unit connected to a first coil of the secondary side of the transformer unit; a second power output unit connected to a part of the first coil of the secondary side of the transformer unit; a synchronization signal detecting unit connected to a third coil of the secondary side of the transformer unit and detecting a switching period of the power input unit; and a synchronization signal output unit controlling an operation of the second power output unit according to the detected signal of the synchronization signal detecting unit.

Abstract: An embodiment provides an inverter transformer comprising: a first bobbin around which a first coil is wound, the first bobbin comprising a first through hole; a second bobbin around which a second coil is wound, the second bobbin comprising a second through hole; a spacer between the first and the second bobbins; and a core inserted into the first and the second through holes.

Abstract: A power supply is provided. The power supply comprises: a power input unit switching an input power; a transformer unit inducing an output power of the power input unit to a secondary side; a first power output unit connected to a first coil of the secondary side of the transformer unit; a second power output unit connected to a part of the first coil of the secondary side of the transformer unit; a synchronization signal detecting unit connected to a third coil of the secondary side of the transformer unit and detecting a switching period of the power input unit; and a synchronization signal output unit controlling an operation of the second power output unit according to the detected signal of the synchronization signal detecting unit.

Abstract: A switching mode power supply (SMPS) is presented to compensate for variations of maximum output power caused by variations of input power. The output power varies according to variations of input power because of a propagation delay of the SMPS. To compensate for the propagation delay, a reference voltage for turning off a switching MOS transistor is differently established depending on the input voltage. The variation of maximum output power according to the input voltage is prevented by differentiating the turned-off time of the reference voltage for turning off a main switch, such as a switching MOS transistor according to the input voltage.

Abstract: A synchronous full bridge rectifier is controlled to provide a power factor near unity. The full bridge rectifiers are transistors each with a controlling input. The AC input signal and currents within the circuit are sensed and sent to a controller. In response, the controller output control signals to turn on/off the rectifying MOSFETS on a timely basis to form a power factor of near one with respect to the AC input signal. The full wave rectifier is made of N-channel MOSFET's, some with fast body diodes. The MOSFET's are rectifiers and PFC control elements. The result is a one stage synchronous rectifier with PFC. A solid state precision analog differential amplifier senses the AC line waveform and high frequency current transformers sense the currents. The controller accepts the inputs of the amplifier and the sensed currents and outputs control signals that turn on and off the four MOSFET's.

Abstract: In one embodiment, a switching mode power supply (SMPS) include: a power supply for supplying power to a secondary coil of a transformer according to an operation of a main switch, the main switch being coupled to a primary coil of the transformer; a feedback circuit for generating a feedback voltage corresponding to an output voltage; a control module for stopping the main switch when the feedback voltage is lower than a reference voltage in a standby operation mode; an integrated circuit (IC) power unit for generating a constant voltage, the IC power supply being coupled to the secondary coil of the transformer; and a current generator for using the constant voltage to generate a plurality of constant currents for operating a plurality of ICs, and generating a constant current from among the constant currents when the main switch performs no switching on/off operation.

Abstract: A synchronous full bridge rectifier is controlled to provide a power factor near unity. The full bridge rectifiers are transistors each with a controlling input. The AC input signal and currents within the circuit are sensed and sent to a controller. In response, the controller output control signals to turn on/off the rectifying MOSFETS on a timely basis to form a power factor of near one with respect to the AC input signal. The full wave rectifier is made of N-channel MOSFET's, some with fast body diodes. The MOSFET's are rectifiers and PFC control elements. The result is a one stage synchronous rectifier with PFC. A solid state precision analog differential amplifier senses the AC line waveform and high frequency current transformers sense the currents. The controller accepts the inputs of the amplifier and the sensed currents and outputs control signals that turn on and off the four MOSFET's.

Abstract: A switching mode power supply is described. The switching mode power supply includes a power supply unit, a mode setting unit, a feedback circuit, and a switching controller. The switching controller controls a main switch to carry out a switching operation at a predetermined duty according to feedback voltage charged in a first capacitor in the normal operation mode, and controls the main switch to repeat a switching on state and a switching off state in the standby mode. The current inputted to the switching controller varies with the operation mode. Accordingly, the minimum voltage for operating the switching controller can be maintained even if output voltage is decreased in the standby mode, and unnecessary power consumption in the switching controller can be reduced.

Abstract: Provided is a control module circuit for use with a switching power supply (SPS). The control module circuit has normal and standby operation modes controls switch-on/off operations of a switching device by using a feedback voltage that is inversely proportional to an output voltage. The control module circuit includes a voltage set-up unit and a switching control signal generating unit. The voltage set-up unit provides a first voltage used for a switch-on operation of the switching device in response to changes in the feedback voltage and a second voltage used for a switch-off operation of the switching device in response to changes in the feedback voltage, in the standby operation mode. The switching control signal generating unit generates a control signal used to turn on the switching device when the first voltage is provided from the voltage set-up unit and a control signal used to turn off the switching device when the second voltage is provided from the voltage set-up unit.

Abstract: A switched-mode power supply (SMPS) that operates in a burst mode when an electronic device that receives power from the SMPS demands a low level of power as when in a stand-by mode or cut-off mode. The SMPS contains a first power supply unit for receiving a power and rectifying it, and, according to a level of an output for the load, distinguishing between a normal mode and a burst mode to perform switching according to a timing corresponding to the normal mode and the burst mode to supply a first power. The SMPS also contains an output power supply unit for receiving the first power from the first power supply unit according to a winding ratio of a coil to generate a power for driving the load.

Abstract: A switching power supply includes a switch, a bias-sensor to sense the switch-voltage, and a zero-crossing detector (ZCD) to sense time instances when the bias-sensor voltage crosses zero. ZCD generates a ZCD-signal, which transitions between a first and a second level at the sensed crossing instances, with a delay. ZCD-signal is coupled to a blanking circuit, generating a blank-signal and a pulse-signal, controlling the switch. The on-time of the switch can be modified by the input voltage and load. The blank-signal between on-times is adjusted to compensate for this modification, keeping the switching frequency below a predetermined limit and reducing the switching frequency. The switching power supply further includes a pulse width modulation (PWM) signal generator, coupled to the blanking circuit and to the switch. PWM signal generator turns on the switch controlled by the pulse-signal of the blanking circuit. Blanking circuit is controlled by either the on-time or a control voltage and input voltage.

Abstract: In one embodiment, a switching mode power supply (SMPS) may comprise: a power supply for supplying power to a secondary coil of a transformer according to an operation of a main switch, the main switch being coupled to a primary coil of the transformer; a feedback circuit for generating a feedback voltage corresponding to an output voltage; a control module for stopping the main switch when the feedback voltage is lower than a reference voltage in a standby operation mode; an integrated circuit (IC) power unit for generating a constant voltage, the IC power supply being coupled to the secondary coil of the transformer; and a current generator for using the constant voltage to generate a plurality of constant currents for operating a plurality of ICs, and generating a constant current from among the constant currents when the main switch performs no switching on/off operation.

Abstract: A switching mode power supply (SMPS) is presented to compensate for variations of maximum output power caused by variations of input power. The output power varies according to variations of input power because of a propagation delay of the SMPS. To compensate for the propagation delay, a reference voltage for turning off a switching MOS transistor is differently established depending on the input voltage. The variation of maximum output power according to the input voltage is prevented by differentiating the turned-off time of the reference voltage for turning off a main switch, such as a switching MOS transistor according to the input voltage.

Abstract: An inverter driver comprises: an inverter circuit including first and second switches, inverting DC components into AC components in response to switching by the first and second switches to drive a load; a control signal supply outputting a first voltage corresponding to a voltage caused by sensing the current flowing to the load, and outputting a second voltage, and a third voltage generated by multiplying the first voltage by a gain; a frequency controller including a capacitor and an oscillator, controlling a first current charged in/discharged from the capacitor through the oscillator in response to the first voltage; and a duty controller comparing the third voltage and a fourth voltage charged in the capacitor, and controlling the duty of the first and second switches.

Abstract: A switching power supply includes a switch, a bias-sensor to sense the switch-voltage, and a zero-crossing detector (ZCD) to sense time instances when the bias-sensor voltage crosses zero. ZCD generates a ZCD-signal, which transitions between a first and a second level at the sensed crossing instances, with a delay. ZCD-signal is coupled to a blanking circuit, generating a blank-signal and a pulse-signal, controlling the switch. The on-time of the switch can be modified by the input voltage and load. The blank-signal between on-times is adjusted to compensate for this modification, keeping the switching frequency below a predetermined limit and reducing the switching frequency. The switching power supply further includes a pulse width modulation (PWM) signal generator, coupled to the blanking circuit and to the switch. PWM signal generator turns on the switch controlled by the pulse-signal of the blanking circuit. Blanking circuit is controlled by either the on-time or a control voltage and input voltage.

Abstract: A flyback converter detects an output voltage at the primary coil without using a photo coupler and provides an essentially constant output voltage independent of the load size, thereby minimizing the number of additional coils used in the transformer circuit to realize simple construction and providing accurate power control. In one embodiment, the flyback converter includes: a transformer for changing an input voltage to a predetermined level according to a winding ratio; an output unit for rectifying the voltage signal output from the transformer into a DC signal to drive a load; a switch coupled to the primary coil of the transformer for controlling the on/off state of a power at the primary coil according to a switching control signal; a feedback unit generating a feedback signal and detecting a current of the switch to correct the feedback signal; and a switching controller operating according to the feedback signal.

Abstract: Provided is a control module circuit for use with a switching power supply (SPS). The control module circuit has normal and standby operation modes controls switch-on/off operations of a switching device by using a feedback voltage that is inversely proportional to an output voltage. The control module circuit includes a voltage set-up unit and a switching control signal generating unit. The voltage set-up unit provides a first voltage used for a switch-on operation of the switching device in response to changes in the feedback voltage and a second voltage used for a switch-off operation of the switching device in response to changes in the feedback voltage, in the standby operation mode. The switching control signal generating unit generates a control signal used to turn on the switching device when the first voltage is provided from the voltage set-up unit and a control signal used to turn off the switching device when the second voltage is provided from the voltage set-up unit.

Abstract: An inverter driver comprises: an inverter circuit including first and second switches, inverting DC components into AC components in response to switching by the first and second switches to drive a load; a control signal supply outputting a first voltage corresponding to a voltage caused by sensing the current flowing to the load, and outputting a second voltage, and a third voltage generated by multiplying the first voltage by a gain; a frequency controller including a capacitor and an oscillator, controlling a first current charged in/discharged from the capacitor through the oscillator in response to the first voltage; and a duty controller comparing the third voltage and a fourth voltage charged in the capacitor, and controlling the duty of the first and second switches.

Abstract: A switching mode power supply is described. The switching mode power supply includes a power supply unit, a mode setting unit, a feedback circuit, and a switching controller. The switching controller controls a main switch to carry out a switching operation at a predetermined duty according to feedback voltage charged in a first capacitor in the normal operation mode, and controls the main switch to repeat a switching on state and a switching off state in the standby mode. The current inputted to the switching controller varies with the operation mode. Accordingly, the minimum voltage for operating the switching controller can be maintained even if output voltage is decreased in the standby mode, and unnecessary power consumption in the switching controller can be reduced.

Abstract: A flyback converter detects an output voltage at the primary coil without using a photo coupler and provides an essentially constant output voltage independent of the load size, thereby minimizing the number of additional coils used in the transformer circuit to realize simple construction and providing accurate power control. In one embodiment, the flyback converter includes: a transformer for changing an input voltage to a predetermined level according to a winding ratio; an output unit for rectifying the voltage signal output from the transformer into a DC signal to drive a load; a switch coupled to the primary coil of the transformer for controlling the on/off state of a power at the primary coil according to a switching control signal; a feedback unit generating a feedback signal and detecting a current of the switch to correct the feedback signal; and a switching controller operating according to the feedback signal.