Abstract: In a computing device, a computerized method and a non-transitory storage medium are applied in checking a stored wiring diagram for high-noise components in close proximity to signal lines. An electronic component is selected in a PCB wiring file. A checking range of the selected electronic component is determined for searching for one or more signal transmission lines which pass within the checking range in the PCB wiring file. Basic information of the one or more signal transmission lines is recorded into a result list which is displayed on a display unit of the computing device.

Abstract: A Marchand balun circuit includes a Marchand balun, an unbalanced matching circuit, and a balanced matching circuit. The Marchand balun includes an unbalanced terminal, and two balanced terminals. The unbalanced matching circuit includes a first and the second impedances which are connected between the unbalanced terminal and ground in series, and a first resistor which is connected between ground and a connection node of the first and the second impedances. The balanced matching circuit includes a third and a fourth impedances which are connected between one balanced terminal and ground in series, a fifth and a sixth impedance which are connected between the other balanced terminal and ground in series, a second resistor which is connected between ground and a connection node of the third and the fourth impedances, and a third resistor which is connected between ground and a connection node of the fifth and the sixth impedances.

Abstract: A printed circuit board includes a layer. A layer of copper is covered on a surface of the layer. A through hole extends through the printed circuit board. A thermal engraving is defined in the surface of the layer, surrounding the through hole and without being covered by the layer of copper. The thermal engraving includes a first opening and a second opening. The first opening of the thermal engraving faces an output terminal of the power supply, and is non-contiguous with the second opening.

Abstract: A printed circuit board includes a layer. A layer of copper is covered on a surface of the layer. A through hole passes through the printed circuit board. An approximately C-shaped thermal engraving is defined in the surface of the layers, surrounding the through hole and without being covered by the layer of copper. An opening of the thermal engraving faces an output terminal of the power supply.

Abstract: In a method for analyzing a signal group delay of a printed circuit board (PCB) using a computing device, the computing device connects to a signal measuring device that measures S-parameters from a pair of data signal line and clock signal line of the PCB. The method analyzes a differential loss coefficient of the data signal line and the clock signal line based on the S-parameters, and calculates a first signal delay of the data signal line and a second signal delay of the clock signal line according to the differential loss coefficient. The method further analyzes a signal group delay of the PCB according to the first signal delay and the second signal delay, and displays the signal group delay on a display device if the signal group delay does not satisfy a PCB design specification.

Abstract: In a method of managing process factors that influence electrical properties of printed circuit boards (PCBs), n process factors are arranged in an order according to different influence to one kind of electrical property of the PCBs. The different influence is determined by first experiments designed using the Taguchi method. M process factors that have important influence to the electrical property are obtained from the n process factors according to the order to design second experiments. A computing formula for the electrical property is fitted using the m process factors according to simulated results of the second experiments, and a variation range of each of the m process factors is computed according to the computing formula.

Abstract: A printed circuit board includes a signal layer, a dielectric layer, and a reference layer. The signal layer includes a pair of differential signal lines. The dielectric layer is sandwiched between the signal layer and the reference layer. A first void is defined in the reference layer between projections of the pair of differential signal lines. Two second voids are defined in the reference layer at opposite sides of the projections of the pair of differential signal lines.

Abstract: A differential signal transmission device transmits N differential signal pairs from a differential signal generator to a number of receiving terminals. The N differential signal pairs include N positive signals and N negative signals. The N positive signals are clustered at a first positive clustering point. The first positive clustering point is connected to a second positive clustering point via a first matching resistor. The second positive clustering point is grounded via a first grounding resistor, and outputs a number of positive signals to the number of receiving terminals respectively. The N negative signals are clustered at a first negative clustering point. The first negative clustering point is connected to a second negative clustering point via a second matching resistor. The second negative signal clustering point is grounded via a second grounding resistor, and outputs a number of negative signals to the number of receiving terminals respectively.

Abstract: An exemplary probe apparatus includes a fixture, a first probe assembly, a motor, a lead screw, two guide members, a second probe, and a reduction gear unit. The first probe assembly is fixedly attached to the fixture and includes a first probe. The motor has a drive shaft attached to the fixture. The lead screw is coupled to the fixture. The two guide members are attached to the fixture and parallel to the lead screw. The second probe assembly is moveably attached to the lead screw and the at least one guide member, and includes a second probe. The reduction gear unit is coupled to the drive shaft and the lead screw to transmit power from the motor to the second probe assembly through the lead screw. The second probe assembly is configured for moving the second probe towards or away from the first probe along the two guide members.

Abstract: An exemplary antistatic circuit board includes a first outer layer, a second outer layer, a first ground layer, and a second ground layer. The first ground layer and the second ground layer are positioned between the first outer layer and the second outer layer. The first ground layer is adjacent to the first outer layer and the second ground layer is adjacent to the second outer layer. The antistatic circuit board defines two position holes each penetrating through the first ground layer and the second ground layer. Two circuit grounds are wired on the first ground layer and the second ground layer, respectively. The second ground layer further includes a chassis ground. Each of the position holes also penetrates through the chassis ground.

Abstract: In a method of optimizing parameters of electronic components on printed circuit boards (PCBs), a first experiment table for m variables of one type of parameter of P electronic components on a PCB is designed using n values of each variable and the RSM. P EHs of each first experiment are obtained by simulating, and P EH empirical formulas are computed according to the P EHs. A second experiment table for the m variables is designed using n? values of each variable and the full factorial design, and P EHs of each second experiment are computed using the P EH empirical formulas. Experiments, all the P EHs of which are greater than 1, are filtered from the second experiment tables, and an average EH of each filtered experiment is computed to pick an experiment the average EH of which is the greatest. The values of the m variables in the picked experiment are considered as optimized.

Abstract: A printed circuit board includes a base, a signal layer lying on the base, and a number of pairs of differential signal traces positioned on the signal layer. The base is made of a grid of glass fiber bundles filled with epoxy resin. Each pair of differential signal traces includes a first signal trace and a second signal trace. Each of the first and second signal traces extends in a zigzag pattern. The first signal trace includes a number of wave crests and wave troughs. The wave crests define a reference straight line that connects all the wave crest of the first signal trace. The ratio of the distance from each wave crest to the reference straight line to the orthogonal distance between each wave crest and an adjacent wave trough along the reference straight line is 1:5.

Abstract: A printed circuit board includes a first layout layer, a second layout layer, a copper foil layer, a first via and a second via. The first layout layer has a first signal line and a second signal line, each of which has a curved first portion. The second layout layer has a third signal line and a fourth signal line, each of which also has a curved first portion. The curved first portions of the first signal line, the second signal line, the third signal line and the fourth signal line are coupled to the first via and the second via. In this case, the curved first portions of the first signal line, the second signal line, the third signal line and the fourth signal line cooperatively generate spiral inductance characteristic.

Abstract: A printed circuit board is constructed from various woven fiberglass fabrics, strengthened and bound together with epoxy resin, and includes a signal layer. The signal layer includes a positive differential signal line and a negative differential signal line laid out in parallel following a zig-zag pattern. A first distance and a second distance is designed at a ratio of 1:7. The first distance is a perpendicular distance between a highest point of the negative differential signal line and a reference line formed by connecting all lowest points of the negative differential signal line. The second distance is a perpendicular distance between a lowest point and an adjacent highest point of the negative differential signal line along the direction of the reference line.

Abstract: In a method of optimizing parameters of electronic components on printed circuit boards (PCBs), a first experiment table for m variables of one type of parameter of P electronic components on a PCB is designed using n values of each variable and the RSM. P EHs of each first experiment are obtained by simulating, and P EH empirical formulas are computed according to the P EHs. A second experiment table for the m variables is designed using n? values of each variable and the full factorial design, and P EHs of each second experiment are computed using the P EH empirical formulas. Experiments, all the P EHs of which are greater than 1, are filtered from the second experiment tables, and an average EH of each filtered experiment is computed to pick an experiment the average EH of which is the greatest. The values of the m variables in the picked experiment are considered as optimized.

Abstract: A printed circuit board includes a layer. A layer of copper is covered on a surface of the layer. A through hole extends through the printed circuit board. A thermal engraving is defined in the surface of the layer, surrounding the through hole and without being covered by the layer of copper. The thermal engraving includes a first opening and a second opening. The first opening of the thermal engraving faces an output terminal of the power supply, and is non-contiguous with the second opening.

Abstract: A portable device includes a central processing unit, a vibration sensor to sense vibration of the portable device, an image processing unit to process image data, and a memory unit storing a vibration reduction module. The vibration reduction module includes a vibration signal collecting sub-module to collect a vibration signal of the portable device, a filter sub-module to filter noise of the vibration signal, a vibration offset calculating sub-module to calculate a vibration offset of the portable device according to the filtered vibration signal, a vibration compensation calculating sub-module to calculate a compensation value corresponding to the vibration offset of the portable device, and an image controlling sub-module to control images of the portable device to move a distance which is equal to the compensation value via the image processing unit, to make the images of the portable device keep a fixed position.

Abstract: A printed circuit board includes a plurality of power layers. Each power layer defining a number of vias arranged in a number of rows. The number of the power layers is N (N>3). The power layers are defined as a 1st, 2nd, . . . , Nth power layer. The vias of the 1st power layer are connected to other power layers by a step-shaped connection means.

Abstract: In a method of managing process factors that influence electrical properties of printed circuit boards (PCBs), n process factors are arranged in an order according to different influence to one kind of electrical property of the PCBs. The different influence is determined by first experiments designed using the Taguchi method. M process factors that have important influence to the electrical property are obtained from the n process factors according to the order to design second experiments. A computing formula for the electrical property is fitted using the m process factors according to simulated results of the second experiments, and a variation range of each of the m process factors is computed according to the computing formula.

Abstract: A computing device and a method reads a circuit board layout file from a storage device, and selects a first signal transmission line from circuit board layout file as a target line. The computing device and method computes a distance between the target line and the aggressor line corresponding to each unit sample length. If the distance is more than or equal to a height of a sample region, the computing device and method defines the height of the sample region as a crosstalk space between the target line and the aggressor line corresponding to a unit sample length. Otherwise, if the distance is less than the height of the sample region, the computing device and method defines the distance as the crosstalk space between the target line and the aggressor line corresponding to the unit sample length.