Abstract: An asymmetric half-bridge flyback circuit-based converter is provided. The converter is configured to convert an alternating current (AC) input at an AC input end into a direct current (DC) within a preset voltage value range. The converter includes a full-bridge rectifier circuit, a half-bridge circuit, a resonant circuit, a transformer, a load output circuit, and a control circuit.

Abstract: An asymmetric half-bridge flyback circuit-based converter is provided. The converter is configured to convert an alternating current (AC) input at an AC input end into a direct current (DC) within a preset voltage value range. The converter includes a full-bridge rectifier circuit, a half-bridge circuit, a resonant circuit, a transformer, a load output circuit, and a control circuit.

Abstract: A method includes comparing, by a voltage-second (VS) controller, a first duty cycle used to control a first switch at a primary side of a power transformer of a DC-to-DC converter with a threshold. The method further includes if a value of the first duty cycle is less than the threshold, controlling, by the VS controller, a second duty cycle used to control a second switch at a secondary side of the power transformer, and maintaining a voltage level at an output voltage node at a non-zero value, and if the value of the first duty cycle is greater than the threshold, controlling, by an output voltage loop, the second duty cycle based on the first duty cycle, and monotonically increasing the voltage level the at the output voltage node from the non-zero value to a predetermined value.

Abstract: A method includes comparing, by a voltage-second (VS) controller, a first duty cycle used to control a first switch at a primary side of a power transformer of a DC-to-DC converter with a threshold. The method further includes if a value of the first duty cycle is less than the threshold, controlling, by the VS controller, a second duty cycle used to control a second switch at a secondary side of the power transformer, and maintaining a voltage level at an output voltage node at a non-zero value, and if the value of the first duty cycle is greater than the threshold, controlling, by an output voltage loop, the second duty cycle based on the first duty cycle, and monotonically increasing the voltage level the at the output voltage node from the non-zero value to a predetermined value.

Abstract: One embodiment of the invention relates to a switching control system for controlling an isolated power supply. The system includes a pulse-width modulation (PWM) switching controller configured to generate at least one primary switching signal having a first duty-cycle for activating at least one primary-side switch of the isolated power supply. A synchronous rectifier (SR) switching controller is configured to generate at least one SR switching signal having a second duty-cycle for activating at least one SR switch of the isolated power supply to conduct an output current through a secondary winding of a transformer and an output inductor to generate an output voltage, the second duty-cycle being independent of the first duty-cycle in a soft-start mode.

Abstract: Various embodiments of the present invention provide voltage converters and methods for using such. As one example, a voltage converter is disclosed that includes a transformer with a first winding and a second winding. A voltage is applied to the first winding for a period that is followed by an OFF time. The voltage converter further includes an OFF time controller that is operable to adjust the OFF time based at least in part on a load current traversing the second winding.

Abstract: Various embodiments of the present invention provide voltage converters and methods for using such. As one example, a voltage converter is disclosed that includes a transformer, an operational detector, and a controllable oscillator. The transformer includes a first winding and a second winding, and the operational detector provides an electrical output corresponding to an operational characteristic of the transformer. The controllable oscillator provides a clock output with a frequency corresponding to the electrical output. This clock output at least in part controls application of a voltage input to the first winding.

Abstract: Various embodiments of the present invention provide voltage converters and methods for using such. As one example, a voltage converter is disclosed that includes a transformer with a first winding and a second winding. A voltage is applied to the first winding for a period that is followed by an OFF time. The voltage converter further includes an OFF time controller that is operable to adjust the OFF time based at least in part on a load current traversing the second winding.

Abstract: Various embodiments of the present invention provide voltage converters and methods for using such. As one example, a voltage converter is disclosed that includes a transformer with a first winding and a second winding. A voltage is applied to the first winding for a period that is followed by an OFF time. The voltage converter further includes an OFF time controller that is operable to adjust the OFF time based at least in part on a load current traversing the second winding.

Abstract: One embodiment of the invention relates to a switching control system for controlling an isolated power supply. The system includes a pulse-width modulation (PWM) switching controller configured to generate at least one primary switching signal having a first duty-cycle for activating at least one primary-side switch of the isolated power supply. A synchronous rectifier (SR) switching controller is configured to generate at least one SR switching signal having a second duty-cycle for activating at least one SR switch of the isolated power supply to conduct an output current through a secondary winding of a transformer and an output inductor to generate an output voltage, the second duty-cycle being independent of the first duty-cycle in a soft-start mode.

Abstract: One embodiment of the invention includes a power regulator system. The system includes a switching system configured to generate an output voltage across a load based on a high-side switch coupling a power voltage to an output at an edge-trigger of a PWM control signal having an activation pulse-width of the high-side switch. The system also includes a switch driver system configured to set a duty-cycle of the PWM control signal such that the activation pulse-width of the PWM control signal is based on the power regulator system operating in one of a continuous conduction mode (CCM) and a discontinuous conduction mode (DCM). The edge-trigger of the PWM control signal can occur based on a relative magnitude of the output voltage and the power voltage while operating in the DCM.

Abstract: One embodiment of the invention includes a power regulator system. The system includes a switching system configured to generate an output voltage across a load based on a high-side switch coupling a power voltage to an output at an edge-trigger of a PWM control signal having an activation pulse-width of the high-side switch. The system also includes a switch driver system configured to set a duty-cycle of the PWM control signal such that the activation pulse-width of the PWM control signal is based on the power regulator system operating in one of a continuous conduction mode (CCM) and a discontinuous conduction mode (DCM). The edge-trigger of the PWM control signal can occur based on a relative magnitude of the output voltage and the power voltage while operating in the DCM.

Abstract: Various embodiments of the present invention provide voltage converters and methods for using such. As one example, a voltage converter is disclosed that includes a transformer with a first winding and a second winding. A voltage is applied to the first winding for a period that is followed by an OFF time. The voltage converter further includes an OFF time controller that is operable to adjust the OFF time based at least in part on a load current traversing the second winding.

Abstract: Various embodiments of the present invention provide voltage converters and methods for using such. As one example, a voltage converter is disclosed that includes a transformer, an operational detector, and a controllable oscillator. The transformer includes a first winding and a second winding, and the operational detector provides an electrical output corresponding to an operational characteristic of the transformer. The controllable oscillator provides a clock output with a frequency corresponding to the electrical output. This clock output at least in part controls application of a voltage input to the first winding.

Abstract: A microwave ablation water jet scalpel, used for minimally invasive ablation of human tumor, in the present invention combines a microwave scalpel with a liquid-ejection system in which the liquid-ejecting rate is controllable. The improved microwave scalpel allows normal saline to be ejected into the tissue where the scalpel is working. As a result, this relieves many problems associated with high heat generated during the operation of a microwave.

Abstract: A mobile communication apparatus includes a housing having a recess formed on a top surface thereof, N sets of resilient pins disposed in the recess, and a keypad. The keypad is rotatably mounted in the recess, and N guiding grooves are formed on a bottom surface of the keypad. Each of the guiding grooves corresponds to one of the N sets of resilient pins. The keypad has N sets of first contact points where each set is disposed in the corresponding guiding groove, and N sets of second contact points where each set is disposed in the corresponding guiding groove. When the keypad is positioned at a first position, each set of resilient pins contacts the corresponding set of first contact points, and when the keypad rotates from the first position to a second position, each set of resilient pins contacts the corresponding set of second contact points.