Abstract:
An electronic device reads a layout file of a printed circuit board (PCB) to be manufactured from a storage device, obtains length information and section area information of copper cladding distributed on power source areas and ground trace areas in each of one or more layers of the PCB to be manufactured by analyzing the layout file, and calculates power loss in each of the one or more layers according to the length information, the section area information, a resistance value of the copper cladding, and preset parameters of a power supply module and an integrated circuit (IC) load to be located on the PCB. In response to a determination that the power loss in the layer exceeds a preset range, the electronic device indicates the locations of the power source areas and the ground trace areas of a layer in the PCB layout file which need to be redesigned.
Abstract:
A printed circuit board includes a top layer and a bottom layer. A power supply and an electronic component are located on the top layer. The power supply is connected to the top layer and the bottom layer through a first via. A number of second vias extends through the top layer and the bottom layer, and is electrically connected to the top layer and the bottom layer. A right-angled triangular void area without vias defined therein is formed on the printed circuit board, between the second vias and the electronic component. The second vias are arranged on a hypotenuse of the void area.
Abstract:
A voltage regulating circuit includes a pulse width modulation controller, a current sense circuit, a voltage feedback circuit, and a gain-and-bias circuit. The current sense circuit includes an inductor and a capacitor. The voltage feedback circuit includes first and second resistors. The gain-and-bias circuit includes an operational amplifier. A first terminal of the capacitor is connected to an inverting input terminal of the operational amplifier through a third resistor. A second terminal of the capacitor is connected to a non-inverting input terminal of the operational amplifier through a fourth resistor. The inverting input terminal of the amplifier is connected to an output terminal of the operational amplifier through a fifth resistor. The non-inverting input terminal of the operational amplifier is grounded through a sixth resistor. The output terminal of the operational amplifier is connected to the node between the first and second resistors through a seventh resistor.
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:
An exemplary PCB includes a first reference layer, a first signal layer, and a second signal layer in that order. A first differential pair is arranged in the first signal layer in an edge-coupled structure referencing the first reference layer. A second differential pair is arranged in the second signal layer in edge-coupled structure. A first ground part and a second ground part are symmetrically arranged in the second signal layer and at opposite sides of the second differential pair. The first differential pair is arranged above the first ground part such that a projection of the first differential pair onto the second signal layer having an area coincident with the first ground part. The second differential pair references the first and second ground parts.
Abstract:
A power supply system includes a power supply, a daughterboard, and a motherboard. Output currents of power connectors of the motherboard and impedances of copper foils between every two adjacent power connectors of the motherboard are obtained via simulation. A voltage of one power connector of the motherboard is predetermined. Therefore, desired impedances of copper foils between VRM connectors and corresponding power connectors on the daughter board are determined via calculations, to make currents passing through the power connectors of the motherboard equal to each other.
Abstract:
The present disclosure provides for many different embodiments. An exemplary method can include providing a blank mask and a design layout to be patterned on the blank mask, the design layout including a critical area; inspecting the blank mask for defects and generating a defect distribution map associated with the blank mask; mapping the defect distribution map to the design layout; performing a mask making process; and performing a mask defect repair process based on the mapping.
Abstract:
An all digital phase lock loop is disclosed, including a digitally controlled oscillator, a phase detector, and a loop filter. The digitally controlled oscillator is controlled by an oscillator tuning word to generate a variable signal. The oscillator tuning word includes a first tuning word and a second tuning word, where the frequency range of the digitally controlled oscillator, capable to be adjusted by the second tuning word, is broader than that capable to be adjusted by the first tuning word. The phase detector detects a phase error between the variable signal and a reference signal. The phase error is received by the loop filter to output the oscillator tuning word. The loop filter has several stages of the low pass filters and a modification circuit. The modification circuit detects two filter outputs from two low pass filters among the filters and accordingly adjusts the second tuning word.
Abstract:
An equalizer includes a first resistor and a capacitor connected in parallel. The positive terminal of the capacitor is connected to a signal transmission line on a blah printed circuit board. The negative terminal of the capacitor is connected to ground through a second resistor. A connector including the equalizer and a printed circuit board including the connector are also provided.
Abstract:
A method for selecting a ferrite bead for a filter to avoid a peak value in a frequency response curve of the filter is provided. The method includes the steps of: building an equivalent model database including parameters of equivalent models of ferrite beads, the parameters including an inductance and a capacitance of a corresponding equivalent model of each ferrite bead; calculating parameters of a desired ferrite bead in the filter based on parameters of the filter, the parameters of the ferrite bead including an inductance, a capacitance, and a resonant frequency; adjusting parameters of the filter until the calculated resonant frequency equals or approaches a desired resonant frequency, and finding an inductance and a capacitance respectively equaling or approaching the calculated inductance and the calculated capacitance in the database; and selecting a ferrite bead with the appropriate inductance and capacitance as found in the database for the filter.