Abstract: The present invention discloses a compact server power supply having high power density has a casing, a main printed circuit board, a sub-printed circuit board, a power supplying circuit, a power output terminal set and a fan. The power supplying circuit has a primary side circuit unit, a transformer and a secondary side circuit unit. Electric elements of the primary and secondary side circuit units and the transformer are soldered on the main printed circuit board except parts of the electric elements of the secondary side circuit unit are soldered on the sub-printed circuit board. The sub-printed circuit board is vertically mounted and soldered on the main printed circuit board, so the length of the main printed circuit board is shortened to implement the server power supply having a compact size and high power density.

Abstract: A symmetric planar transformer having adjustable leakage inductance has a circuit board, two first bobbins mounted respectively on opposite side surfaces of the circuit board, two primary windings mounted respectively on the first bobbins, two secondary windings disposed respectively between the circuit board and the first bobbins, two second bobbins disposed respectively between adjacent first bobbins and primary windings, two pad sets disposed respectively between adjacent first bobbins and second bobbins, and a magnetic core assembly mounted through the circuit board, the first and second bobbins, the secondary and primary windings and the pad sets. Adjusting the numbers of the at least one pad of each pad set also adjusts distances between the primary and secondary windings to allow the secondary windings to have the same leakage. Thus, a balanced electric current is induced.

Abstract: Methods for forming a pattern in a lithography process for semiconductor wafer manufacturing are provided. In an example, a method includes forming a photoresist layer over a material layer; performing a first exposure process on the photoresist layer, thereby forming an exposed photoresist layer having soluble portions and unsoluble portions; treating the exposed photoresist layer, wherein the treating includes one of performing a second exposure process on the exposed photoresist layer and forming an adsorbing chemical layer over the exposed photoresist layer; and developing the exposed and treated photoresist layer to remove the soluble portions of the photoresist layer, wherein the unsoluble portions of the photoresist layer form a photoresist pattern that exposes portions of the material layer.

Abstract: Methods for forming a pattern in a lithography process for semiconductor wafer manufacturing are provided. In an example, a method includes forming a photoresist layer over a material layer; performing a first exposure process on the photoresist layer, thereby forming an exposed photoresist layer having soluble portions and unsoluble portions; treating the exposed photoresist layer, wherein the treating includes one of performing a second exposure process on the exposed photoresist layer and forming an adsorbing chemical layer over the exposed photoresist layer; and developing the exposed and treated photoresist layer to remove the soluble portions of the photoresist layer, wherein the unsoluble portions of the photoresist layer form a photoresist pattern that exposes portions of the material layer.

Abstract: A burst mode resonant power converter with high conversion efficiency has a rectifier, a power factor correction circuit, a resonant circuit, a controller, and a burst mode triggering unit. The maximum frequency switching end of the controller is connected to a maximum frequency variable circuit. When the load is medium or heavy, the maximum frequency variable circuit increases the maximum switch frequency of the controller. When the load is in the no-load or the light conditions, it reduces the maximum switch frequency thereof. Therefore, the controller reduces the number of times that the resonant circuit switches the bridge switch circuit. The conduction cycle of the 50% pulse signal output to the bridge switch circuit becomes longer. Larger energy can be transmitted at a time to the secondary coil of the transformer. This increases the overall efficiency.

Abstract: A universal input switching power supply has a signal detecting unit, two DC converting units and a physical wiring and controlling unit. The DC converting units are respectively adapted to couple to an AC power source to convert the AC power source to two first DC power sources and changes a voltage of each of the first power sources according to different voltage of the AC power source. The physical wiring and controlling unit is connected to the outputs of the DC converting units and the signal detecting unit and automatically connects the outputs of the PFC circuits in parallel if a high line voltage range of the AC power source is coupled to the full bridge rectifier. On the contrary, the physical wiring and controlling unit automatically connects the outputs of the PFC circuits in serial. Accordingly, the universal input switching power supply has good transmitting efficiency at different AC power source conditions.

Abstract: A power supply having a two-way DC to DC converter has an AC to DC converter and a two-way DC to DC converter. When an AC power is input to the AC to DC converter, the AC to DC converter transforms the AC power to a middle level DC power and the two-way DC to DC converter transforms the middle level DC power to a low level DC power. When the AC power is unavailable and the two-way DC to DC converter obtains an external DC power, the two-way DC to DC converter transforms the external DC power to the middle level DC power. Therefore, if the power supply obtains the external DC power, the power supply can still output the middle level DC power even the AC power is unavailable.

Abstract: A universal input switching power supply has the rectifier, a signal detecting unit detecting a voltage of an external AC power and outputting a detecting signal, a PFC circuit converts a first DC power from the rectifier to a second DC power with different voltage according to the detecting signal; and a parallel and serial type DC to DC converter converting the second DC power with different voltage to a constant voltage of the third DC power. The parallel and serial type DC to DC converter has a transformer having a primary and secondary coils and physically changes a turn ratio of the primary and secondary coils of a transformer thereof according to a voltage ratio of the second DC power and the third DC power. Accordingly, the universal input switching power supply has good transforming efficiency at different AC power source conditions.

Abstract: A symmetric planar transformer having adjustable leakage inductance has a circuit board, two first bobbins mounted respectively on opposite side surfaces of the circuit board, two primary windings mounted respectively on the first bobbins, two secondary windings disposed respectively between the circuit board and the first bobbins, two second bobbins disposed respectively between adjacent first bobbins and primary windings, two pad sets disposed respectively between adjacent first bobbins and second bobbins, and a magnetic core assembly mounted through the circuit board, the first and second bobbins, the secondary and primary windings and the pad sets. Adjusting the numbers of the at least one pad of each pad set also adjusts distances between the primary and secondary windings to allow the secondary windings to have the same leakage. Thus, a balanced electric current is induced.

Abstract: A full bridge phase shifted power supply with synchronous rectification and current doubler and method for dynamically adjusting delay parameters thereof mainly have multiple delay parameter combinations respectively varying with multiple loads and embedded in a controller of the power supply. The delay parameter combinations serve to determine driving waveforms of two rectification switches of a synchronous rectification and current doubler circuit of the power supply. When the load of the power supply varies, the controller dynamically performs a corresponding delay parameter combination so as to vary the driving waveforms of the rectification switches of the synchronous rectification and current doubler circuit and enhance the operating efficiency of the power supply.

Abstract: An AC to DC power converter with hold up time function has a charging switch and a mode switch. The charging switch is connected between an output capacitor of a PFC controlling circuit and an energy-storage capacitor. The mode switch is connected between the energy-storage capacitor and an input of the PFC controlling circuit. The charging and mode switches are controlled by a PFC controller. When AC power is normal, the charging switch turns on and mode switch turns off. Meanwhile, the energy-storage capacitor and the output capacitor are connected in parallel to store energy in the energy-storage capacitor. When the AC power source is interrupted, the charging switch turns off and mode switch turns on. Therefore, the energy-storage capacitor is disconnected from the output capacitor. The PFC circuit obtains power from the energy-storage capacitor and continuous to supply an output voltage for a while.

Abstract: The present invention discloses a compact server power supply having high power density has a casing, a main printed circuit board, a sub-printed circuit board, a power supplying circuit, a power output terminal set and a fan. The power supplying circuit has a primary side circuit unit, a transformer and a secondary side circuit unit. Electric elements of the primary and secondary side circuit units and the transformer are soldered on the main printed circuit board except parts of the electric elements of the secondary side circuit unit are soldered on the sub-printed circuit board. The sub-printed circuit board is vertically mounted and soldered on the main printed circuit board, so the length of the main printed circuit board is shortened to implement the server power supply having a compact size and high power density.

Abstract: A speaker structure contains a removable food container as a resonant box. The speaker structure contains a baffling device. The baffling device contains a baffle and means for retaining an open top of the food container that is attached to the baffle. When the food container is incorporated with the baffling device, the food container works as a conventional resonant box. Furthermore, a user can freely remove the food container from the baffling device and the removed food container may serve its original food-containing function.

Abstract: A solar-powered LED street light that can immediately report its power data. The disclosed LED street light has a solar cell, a switch power supply unit, and a power cable data communicating unit. The mains power cable of the LED street light connects to the switch power supply unit for providing it with DC power. The solar cell has a solar board, a battery and a charge controller. The charge controller can also provide the LED street light with DC power. The charge controller has a power data digital output interface for connecting with the power cable data communicating unit, outputting the power data of the solar cell to the power cable data communicating unit. Through the mains power cable, the status of solar cell of each LED lamp is monitored.

Abstract: A gathering method for a keypad fabrication process, in which a key-top tree is placed into a punching die, the punching die is aligned, a receiving device is disposed under the punching die, an assembly jig is disposed on the receiving device and aligned using an x-y table for gathering a punched-out key-top, a punch disposed above the punching die using another x-y table for allowing the punching die to perform both punching the key-top tree and gathering the punched-out part onto the assembly jig. Each key-top on the key-top tree is punched out and gathered on the assembly jig by repeating the aforementioned steps. Accordingly, the key-tops can be punched out and arranged on the assembly jig with a different pitch from the key-top tree automatically, fast and correctly. A gathering apparatus for a keypad fabrication process is also provided.

Abstract: A jig includes a carrying plate and a temporary adhering layer on the carrying plate, for gathering parts for an assembly after the parts are punched out. The temporary adhering layer includes a temporary adhering material at its surface. The parts for an assembly temporarily adhere to the surface of the temporary adhering layer. The temporary adhering layer may further have impact buffering properties.

Abstract: A coil of a transformer has two side conducting brackets and at least one middle conducting bracket. The middle conducting bracket is elongated or spiral-shaped and has two terminals respectively connected to the side conducting brackets. The side conducting brackets and the at least one middle conducting bracket of some specific type are connected to form different numbers of loops or different types of circuits (series circuits or parallel circuits). Therefore, design and fabrication of the coil is flexible and materials and manufacturing costs are saved. Moreover, the side conducting brackets and the at least one middle conducting bracket require only two or four soldered joints so number of soldered joints required is limited and efficiency of the transformer is improved.

Abstract: A burst mode resonant power converter with high conversion efficiency has a rectifier, a power factor correction circuit, a resonant circuit, a controller, and a burst mode triggering unit. The maximum frequency switching end of the controller is connected to a maximum frequency variable circuit. When the load is medium or heavy, the maximum frequency variable circuit increases the maximum switch frequency of the controller. When the load is in the no-load or the light conditions, it reduces the maximum switch frequency thereof. Therefore, the controller reduces the number of times that the resonant circuit switches the bridge switch circuit. The conduction cycle of the 50% pulse signal output to the bridge switch circuit becomes longer. Larger energy can be transmitted at a time to the secondary coil of the transformer. This increases the overall efficiency.

Abstract: A switching power supply with the increased efficiency at light load has a switching power circuit, a power monitoring circuit and a light load power supplying circuit. The switching power circuit converts an AC power to a stable DC power and sends the DC power to a load according to voltage variation of the load. When the power monitoring circuit detects the AC power and determines that the load is in a light state, the power monitoring circuit controls the light load power supplying circuit to output a small-power DC to the load. As the DC power provided by the light load power supplying circuit is small, the switching loss ratio is lower in its light load state. Therefore, the operating efficiency at the light load state is higher.

Abstract: A connection-sensing DC plug has an insulative body, a connection portion, two power terminals, a conductive sheet and a retractable pin. The connecting portion is adapted to electronically connect to a target device and has an isolation layer and a ground layer. The conductive sheet is mounted in the insulative body and contacts either the isolation layer or the ground layer. The retractable pin is movably mounted in the insulative housing parallel to the connecting portion, with one end securely engaging the conductive sheet and the other end protruding from the insulative body. When the DC plug is connected to the target device, the retractable pin is pressed and moves inward to bend the conductive sheet, turning the conductive sheet to a floating state and resulting in a trigger signal.