Abstract: A resonant power conversion apparatus including a transformer-based resonant converter and first and second switch control units is provided. The transformer-based resonant converter includes a primary switch circuit and a secondary output circuit configured to provide an output voltage to a load. The first switch control unit is configured to control an ON/OFF operation of the primary switch circuit in response to a status of the load. The second switch control unit is configured to determine whether to activate or inactivate the first switch control unit. When the status of the load is the light-loading or the no-loading, the first switch control unit intermittently controls the ON/OFF operation of the primary switch circuit, and meanwhile, the first switch control unit is inactivated during the primary switch circuit is disabled, so as to substantially reduce the light-loading or no-loading loss of the resonant power conversion apparatus.

Abstract: A non-isolated inverter including a DC input-side, a capacitor connected in parallel with the DC input-side, an AC output-side connected in parallel with a load, and first and second bridge-arm units is provided. The first and second bridge-arm units are connected in parallel with the capacitor. The first bridge-arm unit includes a series forward-connection of upper and lower switch-elements, where a common-node of upper and lower switch-elements and a supplying terminal of the second bridge-arm unit are respectively connected to two terminals of the AC output-side. The upper and lower switch-elements are respectively turned on in positive and negative half cycles of an output current of the non-isolated inverter, and the generation of common-mode currents in the non-isolated inverter is suppressed under a clamping action between the upper and lower switch-elements due to there are no high-frequency voltages on the parasitic-capacitors from the non-isolated inverter to the ground.

Abstract: A snubber circuit includes: at least one impedance component, a capacitor, and a Bipolar Junction Transistor (BJT). The snubber circuit is utilized for protecting electric/electronic components, reducing high frequency interference and spike voltage, and enhancing efficiency. In particular, the at least one impedance component in the snubber circuit can be at least one zener diode, where regarding protecting electric/electronic components, reducing high frequency interference and spike voltage, and enhancing efficiency, the performance of the snubber circuit in a situation where the zener diode is utilized is better than that of the snubber circuit in a situation where other types of impedance components are utilized. An associated method of using a BJT in a snubber circuit is also provided.

Abstract: A DC-to-DC converter adapted for generating a power voltage required by a load and including a buck circuit and a boost circuit is provided. The buck circuit is used for receiving a DC input voltage, and outputting the power voltage by performing a buck process to the DC input voltage, or directly outputting the DC input voltage according to a first control signal. The boost circuit is used for receiving the power voltage or the DC input voltage both output from the buck circuit, and outputting the power voltage to the load by performing a boost process to the DC input voltage output from the buck circuit, or directly outputting the power voltage output from the buck circuit to the load according to a second control signal.

Abstract: An isolated gate driver including a driving control circuit, an isolated transformer, an anti-circuit and a secondary processing circuit is provided. The driving control circuit is configured to generate a driving PWM signal for driving a power switch tube. The isolated transformer has a primary winding and a secondary winding. The anti-circuit is connected between the driving control circuit and the primary winding of the isolated transformer, and is configured to suppress a variation of an induced voltage in the secondary winding of the isolated transformer when a duty cycle of the driving PWM signal is sharply decreased. The secondary processing circuit is connected in parallel with the secondary winding of the isolated transformer, and is configured to perform a voltage clamping action on a gate-source voltage of the power switch tube when the duty cycle of the driving PWM signal is sharply decreased.

Abstract: A power device suited for being assembled in a chassis and connected with a plug is provided. The power device includes a housing, and a receptacle, a spring clamp, a position limiting element disposed on the housing. The plug is removably connected to the receptacle. The spring clamp has a moving end. The position limiting element is located between the spring clamp and the receptacle. The position limiting element and the moving end of the spring clamp are linked together to move between a first position and a second position relative to the housing. When the plug connects to the receptacle, the position limiting element is interfered with the plug and the spring clamp simultaneously so that the spring clamp is constrained at the first position.

Abstract: A non-isolated resonant converter is provided. The provided non-isolated resonant converter includes a switch circuit, a resonant circuit and a rectifying-filtering circuit. The switch circuit, the resonant circuit and the rectifying-filtering circuit are sequentially connected. The resonant circuit includes an auto-transformer, a capacitor and an inductor, wherein the capacitor and the inductor are connected to the auto-transformer. The configuration of the provided non-isolated resonant converter has small size, low loss and high power density.

Abstract: An AC-to-DC conversion apparatus is provided, and which includes a first switch-element, an output capacitor and a bridgeless power-factor-correction (PFC) circuit. The bridgeless PFC circuit is coupled to an AC input, and includes a first inductor, a second inductor and a bridge circuit constructed by second to fifth switch-elements. The first switch-element is connected between bridgeless PFC circuit and the output capacitor. Under such circuit configuration and suitable control manner, the common-mode interference in the provided AC-to-DC conversion apparatus is lowered and thus reducing the power loss.

Abstract: A three-phase boost-buck PFC converter including three independent single-phase boost-buck PFC circuits respectively is provided, which are capable of performing PFC on each phase of the three-phase power. The single-phase boost-buck PFC circuit is composed of two single-phase boost-buck converters independently working in a positive and a negative half cycle of an input voltage, and the two single-phase boost-buck converters are connected in parallel at an input side, and are connected in series at an output side, and each of the single-phase boost-buck converters is composed of a front-end boost circuit and a back-end buck circuit connected in cascade. Compared to the existing technique, regardless of a boost mode or a buck mode, the conduction loss is effectively reduced, and the whole system efficiency is effectively improved.

Abstract: A bootstrap gate driver including a load indication unit, a bootstrap gate-drive unit and a drive-control unit is provided. The load indication unit is configured to generate a load indication signal in response to a state of a load. The bootstrap gate-drive unit is configured to drive a switch-transistor circuit in response to an inputted pulse-width-modulation (PWM) signal, wherein the switch-transistor circuit has a high-side driving path and a low-side driving path. The drive-control unit is coupled to the load indication unit and the bootstrap gate-drive unit, and configured to enable or disable the high-side driving path in response to the load indication signal. In the invention, the operation of the low-side driving path is not affected by enabling or disabling the high-side driving path.

Abstract: A direct current (DC)-to-DC conversion apparatus is provided. The provided DC-to-DC conversion apparatus is composed of two boost circuits, in which inputs of both boost circuits are connected in parallel, and outputs of both boost circuits are connected in series. Accordingly, when the provided DC-to-DC conversion apparatus is operated, the DC input power would be firstly sampled and determined, and then the operations of the first and the second switch devices disposed therein would be controlled in response to the sampled-determined result, such that both boost circuits would be respectively operated in different input conditions, for example, the input is normally-connected or the input is reverse-connected. Accordingly, regardless of the input of normal connection or the input of reverse connection, the provided DC-to-DC conversion apparatus can perform the function of DC-to-DC conversion, thereby enabling the applied product to be normally operated even the input is reverse-connected.

Abstract: A power converter includes an output unit, a first transformer, a switch unit, and a processing unit. The first transformer includes a primary winding and a secondary winding. The primary winding is coupled between an input voltage and a first node. The switch unit is coupled between the first node and a second node. The processing unit is coupled between the input voltage and the first node. When the switch unit is in an OFF state, the processing unit is used to receive a first sensing voltage and store a sensing power of the first sensing voltage through a first path, isolate the first sensing voltage from feeding in through a second path different from the first path simultaneously, and then release the stored sensing power through the second path. The first sensing voltage is generated as the switch unit switches from an ON state to the OFF state.

Abstract: A post regulation control circuit aims to monitor ancillary output power generated from a power supply. The power supply includes at least one primary output circuit to provide a primary output power. A post regulation circuit obtains the primary output power and regulate to an ancillary output power. The monitor circuit sets an abnormal level and obtains a detection power from the post regulation circuit to compare with the abnormal level. Determining whether to output a driving pulse wave according to the detection power is over the abnormal level or not, or stop outputting the driving pulse wave.

Abstract: A power transforming circuit board includes a substrate and at least one power output structure. The substrate has at least one power transforming circuit and at least one pair of power input holes. The power output structure is disposed on the substrate. Each power output structure is electrically connected with one corresponding power transforming circuit. Each power output structure has at least one cable connecting hole. The normal direction of each power output structure is oriented at an angle with respect to the normal direction of the substrate.

Abstract: An LED backlight driving circuit including a boost circuit and a transformer current balance circuit is provided. The boost circuit provides a total current for n LED strings, and the transformer current balance circuit is coupled to the LED strings and includes n?1 transformers. A first LED current-balance-circuit (CBC) includes a switching-transistor connected to a secondary-winding of a first-transformer, and an nth LED CBC includes a switching-transistor connected to a primary-winding of an (n?1)th transformer. An ith (1<i<n, n>2) LED CBC includes a switching-transistor sequentially connected to a primary-winding of an (i?1)th transformer and a secondary-winding of an ith transformer. The passive-transformers are applied in the LED driving circuit to implement current balance/equalization, such that the LED backlight driving circuit is suitable for a system with any odd or even number (greater than 1) of the LED strings connected in parallel, so as to reduce the cost of the system.

Abstract: An LED power supply device is provided. In the invention, a digital control device and a programmable interface are used to set an output specification of the LED power supply device, such that one smart LED power supply device can be used to supply power to the LED lamps of different specifications. In this way, it is unnecessary to specifically design and test the power supply devices for the LED lamps of different specifications, so that a design and production cycle of the LED power supply devices and costs thereof are greatly reduced. On the other hand, usage of the digital control device avails monitoring and controlling a state of the LED lamp, for example, implementing temperature control, time control, color and luminance control, etc., by which a service life, efficiency and flexibility of the LED lamp are enhanced.

Abstract: A resonant converter equipped with a phase shifting output circuit includes a resonant circuit to receive input power and regulate to become at least one resonant power, a switch unit to switch an ON period for the input power to pass through the resonant circuit and a power transformation circuit to regulate the resonant power and output a transformed power. The resonant converter further has a primary output circuit and at least one secondary output circuit. The primary output circuit regulates the transformed power to become a primary output power. A resonant control unit captures a feedback signal from the primary output circuit and generates a resonant control signal. A phase shifting control unit receives the resonant control signal and regulate to become a phase shifting driving signal. The secondary output circuit is controlled by the phase shifting driving signal and provides a secondary output power.

Abstract: A current-input-type parallel resonant DC/DC converter and a method thereof are provided. The converter includes an inverter-circuit for inverting/converting an input DC current into a positive-and-negative alternating square-wave-current, a resonant-network for converting the square-wave-current into a sine-voltage, a transformer for realizing the isolation of the power transmission, a full-wave rectifier-circuit for rectifying the sine-voltage, and an output-filter-circuit for producing a DC output-voltage.

Abstract: A switch control circuit for controlling a first switch element and a second switch element within a bridgeless switching circuit is provided. The bridgeless switching circuit generates an output signal according to an alternating current signal. The switch control circuit includes a current generating element and a phase generating element. The current generating element is for sensing a first current flowing through the first switch element and a second current flowing through the second switch element, and generating a phase comparison result according to the first and the second currents. The phase generating element generates a first control signal and a second control signal according to a power factor correction signal and the phase comparison result to control conducting status of the first and the second switch elements, respectively.

Abstract: A passive current balance driving apparatus has a circuit topology composed by several simple passive components and is capable of driving a plurality of LED strings simultaneously. The present passive current balance driving apparatus is mainly configured such that each LED string has the identical load characteristics during the positive and negative half cycles of the AC power. As such, the currents flowing through the respective LED strings are basically/substantially equal, thereby achieving the current balance.