摘要:
A computer motherboard includes a printed circuit board which includes a central processing unit (CPU) socket and a group of memory slots. The group of memory slots includes an in-line type memory slot and a surface mounted device (SMD) type memory slot. The in-line type memory slot includes a number of plated through holes. The SMD type memory slot is set between the in-line type memory slot and the CPU socket. The through holes of the in-line type memory slot are connected to the CPU socket through traces, pads of the SMD type memory slot are connected to corresponding through holes of the in-line type memory slot having the same pin definition.
摘要:
The REVERSING TRANSMISSION includes a shaft, a retainer, a spacing collar, a plurality of reversing members, two gears and two covers. The holder is sleeved on the shaft with spaced sliding notches formed thereon. The spacing collar is mounted on an outer surface of the retainer. The reversing members each includes two spaced swing plates with two reversed spiral teeth dented on two diagonal half surfaces of the two spaced swing plate. The reversing members slide into the sliding notches of the holder with two swing plates distributed at different side of the spacing collar. Each of the gears has a group of spiral teeth formed on the inner side for engaging with the group of spiral teeth of the reversing members, and cogs formed on the outer circumference surface. The covers are mounted on two opposite ends of the holder to keep the reversing member in position.
摘要:
Parameters of a radio frequency filter can be changed by changing structure of each component of the filter. Material of each component, diameters of each of magnetic cylinders, density of each of conductive coils, thickness of a dielectric layer, and thickness of an insulation tube can be changed. When any component needs to be replaced, each cover is rotated, with connection partitions moving to two slots of an insulation portion, to detach the filter.
摘要:
An apparatus for adjusting a differential probe includes a regulator arranged therein capable of adjusting a distance between two tips of the probe. The probe is supported on the apparatus. The apparatus includes a rotatable shaft and a rotatable disk. The rotatable shaft engages with the regulator of the probe. The rotatable disk is mounted surrounding the rotatable shaft and rotatable together with the rotatable shaft. An angular ruler or a radian ruler is described on an outer surface of the rotatable disk to indicate a rotation angle or a rotation radian of the rotatable shaft, therefore the distance between the two tips of the probe are accurately adjusted.
摘要:
A printed circuit board can support different connectors by selectively setting connection components on the printed circuit board without changing wiring of transmission lines or making new vias in the printed circuit board.
摘要:
An automatic system for providing printed circuit board (PCB) layout of a PCB includes an input device, a data processing device, and a storage device. The data processing device includes an invoking module, a calculating module, and a determining module. The invoking module is to read a name and a thickness of each layer of the PCB from the storage device. The calculating module is to calculate an actual length of a via stub of each layer according to the name and thickness of each layer, and calculate an ideal length of the via stub of the PCB according to input information from the input device, and a preset formula. The determining module is to compare the ideal length and the actual length of the via stub of each layer to determine whether the layer can be used as a high-speed signal layout layer or not.
摘要:
Parameters of a radio frequency filter can be changed by changing structure of each component of the filter. Material of each component, diameters of each of magnetic cylinders, density of each of conductive coils, and thickness of each of dielectric layers can be changed. When any component needs to be replaced, the filter can be detached as needed.
摘要:
A system and method for inspecting layout of a printed circuit board (PCB) provides a graphical user interface (GUI). The GUI displays a layout of the PCB. High side pins of a pulse width modulation (PWM) controller and a component connected to a high side pin are found. If the component is a metallic oxide semiconductor field effect transistor (MOSFET), the system calculate absolute a linear distance and a trace distance between a source pin of the MOSFET and a capacitor pin of a coupling capacitor connected to the source pin. If the linear distance, the trace distance and a capacitance of the coupling capacitor accord with a layout standard, the layout of the PCB is determined to be up to standard.
摘要:
A method for testing a characteristic impedance of an electronic component includes sending a positioning command to a control computer through a switch, so as to drive a probe holder of a mechanical arm to position probes of a time domain reflectometer (TDR) on a position of the electronic component. The method further receives measured data collected by the TDR, and compares the measured data with preset standard values to determine if the measured data is acceptable.
摘要:
A testing apparatus is for testing products on an assembly line and includes a worktable, a positioning device, and a testing member. The worktable includes a number of wheels pivotably attached to a bottom thereof, and a number of retractable feet attached to the bottom thereof. The positioning device is attached to the worktable and includes a number of clamping members to position a product to be test. The testing member is attached to the worktable and operated by a control box to move a robot arm with a testing head to test the product.